itu maritime mobile -2 2011
TRANSCRIPT
I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n
Provisions of the TelecommunicationServices applicable or useful to stationsin the Maritime Mobile and MaritimeMobile-Satellite Services
Man
ual f
or us
e by t
he M
ariti
me M
obile
and M
ariti
me M
obile
-Sat
ellite
Ser
vices
En
glish
editi
on 2
011
*36519*
Manualfor use by the Maritime Mobile andMaritime Mobile-Satellite Services
Volume 2
2
English edition 2011
Radiocommunication Bureau
English edition 2011
Radiocommunication Bureau
I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n
Provisions of the Telecommunication
Services applicable or useful to stations
in the Maritime Mobile and Maritime
Mobile-Satellite Services
Manualfor use by the Maritime Mobile and
Maritime Mobile-Satellite Services
Volume 2
THE RADIOCOMMUNICATION SECTOR OF ITU
The role of the Radiocommunication Sector is to ensure the rational, equitable, efficient
and economical use of the radio-frequency spectrum by all radiocommunication
services, including satellite services, and carry out studies without limit of frequency
range on the basis of which Recommendations are adopted.
The regulatory and policy functions of the Radiocommunication Sector are performed
by World and Regional Radiocommunication Conferences and Radiocommunication
Assemblies supported by Study Groups.
Inquiries about radiocommunication matters
Please contact:
ITU
Radiocommunication Bureau
Place des Nations
CH -1211 Geneva 20
Switzerland
Telephone: +41 22 730 5800
Fax: +41 22 730 5785
E-mail: [email protected]
Web: www.itu.int/itu-r
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by fax or e-mail.
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The Electronic Bookshop of ITU: www.itu.int/publications
! ITU 2011
All rights reserved. No part of this publication may be reproduced by any means whatsoever,
without the prior written permission of ITU.
Table of Contents iii
TABLE OF CONTENTS
Manual for use by the maritime mobile and
maritime mobile-satellite services
Page
FOREWORD ............................................................................................ 1
PART A
Extracts from the Constitution and Convention of
the International Telecommunication Union
Constitution (CS) of the International Telecommunication Union
CHAPTER VI – General Provisions Relating to Telecommunications
ARTICLE 33 The Right of the Public to Use the International
Telecommunication Service ................................................. 5
ARTICLE 34 Stoppage of Telecommunications ........................................ 5
ARTICLE 35 Suspension of Services ......................................................... 6
ARTICLE 36 Responsibility ....................................................................... 6
ARTICLE 37 Secrecy of Telecommunications .......................................... 6
ARTICLE 39 Notification of Infringements ............................................... 7
ARTICLE 40 Priority of Telecommunications Concerning Safety of
Life ....................................................................................... 7
ARTICLE 41 Priority of Government Telecommunications ...................... 7
ARTICLE 42 Special Arrangements .......................................................... 8
CHAPTER VII – Special Provisions for Radio
ARTICLE 45 Harmful Interference ............................................................ 8
ARTICLE 46 Distress Calls and Messages ................................................ 9
ARTICLE 47 False or Deceptive Distress, Urgency, Safety or
Identification Signals............................................................ 9
ANNEX Definition of Certain Terms Used in this Constitution, the
Convention and the Administrative Regulations of the
International Telecommunication Union ..................................... 10
iv Maritime Manual
Page
Convention (CV) of the International Telecommunication Union
CHAPTER V – Various Provisions Related to the Operation of
Telecommunication Services
ARTICLE 36 Charges and Free Services ................................................... 12
ARTICLE 38 Monetary Unit ...................................................................... 12
ARTICLE 39 Intercommunication ............................................................. 13
ARTICLE 40 Secret Language ................................................................... 13
ANNEX Definition of Certain Terms Used in this Convention and
the Administrative Regulations of the International
Telecommunication Union ........................................................... 14
PART B
Extracts from the Radio Regulations (RR) (Edition of 2008)
SECTION I – Articles (Extracts)
ARTICLE 1 Terms and definitions ........................................................... 23
ARTICLE 2 Nomenclature ....................................................................... 44
ARTICLE 3 Technical characteristics of stations ..................................... 46
ARTICLE 4 Assignment and use of frequencies ...................................... 48
ARTICLE 5 Frequency allocations ........................................................... 51
ARTICLE 15 Interferences ......................................................................... 55
ARTICLE 17 Secrecy ................................................................................ 61
ARTICLE 18 Licences ................................................................................ 62
ARTICLE 19 Identification of stations ....................................................... 64
ARTICLE 20 Service publications and online information systems .......... 77
ARTICLE 28 Radiodetermination services ................................................ 79
ARTICLE 30 General provisions................................................................ 82
ARTICLE 31 Frequencies for the global maritime distress and safety
system (GMDSS) ................................................................. 85
Table of Contents v
Page
ARTICLE 32 Operational procedures for distress communications in
the global maritime distress and safety system (GMDSS) ... 87
ARTICLE 33 Operational procedures for urgency and safety
communications in the global maritime distress and
safety system (GMDSS) ....................................................... 101
ARTICLE 34 Alerting signals in the global maritime distress and safety
system (GMDSS) ................................................................. 111
ARTICLE 46 Authority of the master ........................................................ 112
ARTICLE 47 Operator’s certificates .......................................................... 113
ARTICLE 48 Personnel .............................................................................. 118
ARTICLE 49 Inspection of stations ............................................................ 120
ARTICLE 50 Working hours of stations .................................................... 121
ARTICLE 51 Conditions to be observed in the maritime services ............. 122
ARTICLE 52 Special rules relating to the use of frequencies .................... 128
ARTICLE 53 Order of priority of communications.................................... 149
ARTICLE 54 Selective calling ................................................................... 149
ARTICLE 56 Narrow-band direct-printing telegraphy ............................... 150
ARTICLE 57 Radiotelephony .................................................................... 151
ARTICLE 58 Charging and accounting for maritime radio-
communications ................................................................... 152
SECTION II – Appendices (Extracts)
APPENDIX 1 (Rev.WRC-07) Classification of emissions and
necessary bandwidths ........................................................... 155
APPENDIX 2 (Rev.WRC-03) Table of transmitter frequency tolerances 160
APPENDIX 3 (Rev.WRC-03) Tables of maximum permitted power
levels for spurious or spurious domain emissions ................ 167
APPENDIX 9 Report of an irregularity or infringement ............................. 179
APPENDIX 10 (Rev.WRC-07) Report of harmful interference ................. 182
APPENDIX 12 Special rules applicable to radiobeacons .............................. 184
APPENDIX 14 (Rev.WRC-07) Phonetic alphabet and figure code ............ 186
APPENDIX 15 (Rev.WRC-07) Frequencies for distress and safety
communications for the Global Maritime Distress and
Safety System (GMDSS) ..................................................... 188
vi Maritime Manual
Page
APPENDIX 16 (Rev.WRC-07) Documents with which stations on
board ships and aircraft shall be provided ............................ 193
APPENDIX 17 (Rev.WRC-07) Frequencies and channelling
arrangements in the high-frequency bands for the
maritime mobile service ....................................................... 195
APPENDIX 18 (Rev.WRC-07) Table of transmitting frequencies in
the VHF maritime mobile band ............................................ 231
SECTION III – Resolutions (Extracts)
RESOLUTION 18 (Rev.WRC-07) Relating to the procedure for
identifying and announcing the position of ships
and aircraft of States not parties to an armed
conflict .................................................................... 237
RESOLUTION 205 (Rev.Mob-87) Protection of the band 406-
406.1 MHz allocated to the mobile-satellite
service ..................................................................... 239
RESOLUTION 207 (Rev.WRC-03) Measures to address
unauthorized use of and interference to
frequencies in the bands allocated to the
maritime mobile service and to the aeronautical
mobile (R) service .................................................. 241
RESOLUTION 331 (Rev.WRC-07) Transition to the Global
Maritime Distress and Safety System (GMDSS) ... 245
RESOLUTION 339 (Rev.WRC-07) Coordination of NAVTEX
services ................................................................... 249
RESOLUTION 342 (Rev.WRC-2000) New technologies to provide
improved efficiency in the use of the band 156-
174 MHz by stations in the maritime mobile
service ..................................................................... 250
RESOLUTION 343 (WRC-97) Maritime certification for personnel
of ship stations and ship earth stations for which
a radio installation is not compulsory ..................... 253
RESOLUTION 344 (Rev.WRC-03) Management of the maritime
mobile service identity numbering resource ........... 256
Table of Contents vii
Page
RESOLUTION 345 (WRC-97) Operation of Global Maritime
Distress and Safety System equipment on and
assignment of maritime mobile service identities
to non-compulsory fitted vessels ............................ 259
RESOLUTION 349 (WRC-97) Operational procedures for
cancelling false distress alerts in the Global
Maritime Distress and Safety System ..................... 261
RESOLUTION 352 (WRC-03) Use of the carrier frequencies
12 290 kHz and 16 420 kHz for safety-related
calling to and from rescue coordination centres ..... 264
RESOLUTION 354 (WRC-07) Distress and safety radiotelephony
procedures for 2 182 kHz ....................................... 266
SECTION IV – ITU-R Recommendations incorporated
by reference (Extracts)
Rec. ITU-R M.489-2 Technical characteristics of VHF radiotelephone
equipment operating in the maritime mobile
service in channels spaced by 25 kHz .................... 275
Rec. ITU-R M.492-6 Operational procedures for the use of direct-
printing telegraph equipment in the maritime
mobile service ......................................................... 278
Rec. ITU-R M.541-9 Operational procedures for the use of digital
selective-calling equipment in the maritime
mobile service ......................................................... 289
Rec. ITU-R M.1171 Radiotelephony procedures in the maritime
mobile service ......................................................... 333
Rec. ITU-R M.1173 Technical characteristics of single-sideband
transmitters used in the maritime mobile service
for radiotelephony in the bands between
1 606.5 kHz (1 605 kHz Region 2) and
4 000 kHz and between 4 000 kHz and
27 500 kHz .............................................................. 345
Rec. ITU-R M.1174-2 Technical characteristics of equipment used for
on-board vessel communications in the bands
between 450 and 470 MHz ..................................... 347
viii Maritime Manual
Page
PART C
Extracts from other ITU-R Recommendations (M and SM Series)
Rec. ITU-R M.493-13 Digital selective-calling system for use in the
maritime mobile service ......................................... 353
Rec. ITU-R M.585-5 Assignment and use of maritime mobile service
identities.................................................................. 399
Rec. ITU-R M.628-4 Technical characteristics for search and rescue
radar transponders ................................................... 407
Rec. ITU-R M.689-2 International maritime VHF radiotelephone
system with automatic facilities based on DSC
signalling format ..................................................... 421
Rec. ITU-R SM.1138-2 Determination of necessary bandwidths
including examples for their calculation and
associated examples for the designation of
emissions ................................................................ 434
Rec. ITU-R M.1467-1 Prediction of sea area A2 and NAVTEX ranges
and protection of the A2 global maritime distress
and safety system distress watch channel ............... 444
Rec. ITU-R M.1842-1 Characteristics of VHF radio systems and
equipment for the exchange of data and
electronic mail in the maritime mobile service
RR Appendix 18 channels ...................................... 462
Table of Contents ix
Page
PART D
Extracts from the International Telecommunication Regulations (Melbourne, 1988)
ARTICLE 1 Purpose and Scope of the Regulations ................................. 475
ARTICLE 2 Definitions ............................................................................ 476
ARTICLE 3 International Network .......................................................... 476
ARTICLE 4 International Telecommunication Services .......................... 477
ARTICLE 5 Safety of Life and Priority of Telecommunications ............. 478
ARTICLE 6 Charging and Accounting ..................................................... 478
ARTICLE 7 Suspension of Services ......................................................... 479
ARTICLE 9 Special Arrangements .......................................................... 479
ARTICLE 10 Final Provisions .................................................................... 480
APPENDIX 1 General Provisions Concerning Accounting ........................ 481
APPENDIX 2 Additional Provisions Relating to Maritime Telecommu-
nications ............................................................................... 485
PART E
Extracts from ITU-T Recommendations
ITU-T Rec. D.90 Charging, billing, international accounting and
settlement in the maritime mobile service .............. 491
ITU-T Rec. F.60 Operational provisions for the international telex
service ..................................................................... 509
ITU-T Rec. F.110 Operational provision for the maritime mobile
service ..................................................................... 516
ITU-T Rec. F.120 Ship station identification for VHF/UHF and
maritime mobile-satellite services .......................... 538
______________
Foreword 1
Foreword
1 The 2011 edition of the Volume 2 of the Manual for use by the Maritime
Mobile and Maritime Mobile-Satellite Services is published in accordance with
Article 20 (No. 20.14) of the Radio Regulations, and results from the revision of texts
contained in Parts A, B, C, E and F of this Volume of the Manual extracted from other
ITU publications. The contents of each Part are listed below and supplementary
information is given to help and inform its users.
2 This Volume, which contains provisions designed to be of use to operators in
the maritime mobile and maritime mobile-satellite services, is divided into the
following six main Parts:
Part A, contains extracts from the Constitution and Convention of the International
Telecommunication Union.
Part B, contains extracts from the Radio Regulations (RR) (Edition of 2008). This Part
is divided into four Sections:
Section I – Articles (Extracts).
Section II – Appendices (Extracts).
Section III – Resolutions (Extracts).
Section IV – ITU-R Recommendations incorporated by reference (Extracts).
Part C, contains extracts from other ITU-R Recommendations (M and SM Series):
– Recommendation ITU-R M.493-13: Digital selective-calling system for use in
the maritime mobile service.
– Recommendation ITU-R M.585-5: Assignment and use of maritime mobile
service identities.
– Recommendation ITU-R M.628-4: Technical characteristics for search and
rescue radar transponders.
– Recommendation ITU-R M.689-2: International maritime VHF radiotelephone
system with automatic facilities based on DSC signalling format.
– Recommendation ITU-R SM.1138-2: Determination of necessary bandwidths
including examples for their calculation and associated examples for the
designation of emissions.
– Recommendation ITU-R M.1467-1: Prediction of sea area A2 and NAVTEX
ranges and protection of the A2 global maritime distress and safety system
distress watch channel.
– Recommendation ITU-R M.1842-1: Characteristics of VHF radio system and
equipment for the exchange of data and electronic mail in the maritime mobile
service RR Appendix 18 channels.
Part D, contains extracts from the International Telecommunications Regulations
(Melbourne, 1988).
2 Maritime Manual
Part E, contains extracts from ITU-T Recommendations:
– ITU-T Recommendation D.90: Charging, billing, international accounting and
settlement in the maritime mobile service.
– ITU-T Recommendation F.60: Operational provisions for the international telex
service.
– ITU-T Recommendation F.110: Operational provisions for the maritime mobile
service.
– ITU-T Recommendation F.120: Ship station identification for VHF/UHF and
maritime mobile-satellite services
_______________
PART A
Extracts from the
Constitution and Convention
of the International
Telecommunication Union
This Part A contains extracts from the Constitution and Convention of the International
Telecommunication Union adopted by the Additional Plenipotentiary Conference
(Geneva, 1992) as amended by the Plenipotentiary Conferences (Kyoto, 1994,
Minneapolis, 1998, Marrakesh, 2002 and Antalya, 2006), also including amendments,
adopted by the Plenipotentiary Conference (Guadalajara, 2010) which will enter into
force on 1 January 2012.
Part A – CS 5
CONSTITUTION (CS) OF THE INTERNATIONAL
TELECOMMUNICATION UNION
CHAPTER VI
General Provisions Relating to Telecommunications
ARTICLE 33 (CS)
The Right of the Public to Use the International
Telecommunication Service
179
PP-98
Member States recognize the right of the public to correspond by
means of the international service of public correspondence. The services,
the charges and the safeguards shall be the same for all users in each
category of correspondence without any priority or preference.
ARTICLE 34 (CS)
Stoppage of Telecommunications
180
PP-98
1 Member States reserve the right to stop, in accordance with their
national law, the transmission of any private telegram which may appear
dangerous to the security of the State or contrary to its laws, to public order
or to decency, provided that they immediately notify the office of origin of
the stoppage of any such telegram or any part thereof, except when such
notification may appear dangerous to the security of the State.
181
PP-98
2 Member States also reserve the right to cut off, in accordance with
their national law, any other private telecommunications which may appear
dangerous to the security of the State or contrary to its laws, to public order
or to decency.
6 Maritime Manual
ARTICLE 35 (CS)
Suspension of Services
182
PP-98
Each Member State reserves the right to suspend the international
telecommunication service, either generally or only for certain relations
and/or for certain kinds of correspondence, outgoing, incoming or in
transit, provided that it immediately notifies such action to each of the
other Member States through the Secretary-General.
ARTICLE 36 (CS)
Responsibility
183
PP-98
Member States accept no responsibility towards users of the inter-
national telecommunication services, particularly as regards claims for
damages.
ARTICLE 37 (CS)
Secrecy of Telecommunications
184
PP-98
1 Member States agree to take all possible measures, compatible with
the system of telecommunication used, with a view to ensuring the secrecy
of international correspondence.
185 2 Nevertheless, they reserve the right to communicate such corre-
spondence to the competent authorities in order to ensure the application of
their national laws or the execution of international conventions to which
they are parties.
Part A – CS 7
ARTICLE 39 (CS)
Notification of Infringements
190
PP-98
In order to facilitate the application of the provisions of Article 6 of
this Constitution, Member States undertake to inform and, as appropriate,
assist one another with regard to infringements of the provisions of this
Constitution, of the Convention and of the Administrative Regulations.
ARTICLE 40 (CS)
Priority of Telecommunications Concerning
Safety of Life
191 International telecommunication services must give absolute
priority to all telecommunications concerning safety of life at sea, on land,
in the air or in outer space, as well as to epidemiological telecom-
munications of exceptional urgency of the World Health Organization.
ARTICLE 41 (CS)
Priority of Government Telecommunications
192 Subject to the provisions of Articles 40 and 46 of this Constitution,
government telecommunications (see Annex to this Constitution,
No. 1014) shall enjoy priority over other telecommunications to the extent
practicable upon specific request by the originator.
8 Maritime Manual
ARTICLE 42 (CS)
Special Arrangements
193
PP-98
Member States reserve for themselves, for the operating agencies
recognized by them and for other agencies duly authorized to do so, the
right to make special arrangements on telecommunication matters which
do not concern Member States in general. Such arrangements, however,
shall not be in conflict with the terms of this Constitution, of the Con-
vention or of the Administrative Regulations, so far as concerns the
harmful interference which their operation might cause to the radio
services of other Member States, and in general so far as concerns the
technical harm which their operation might cause to the operation of other
telecommunication services of other Member States.
CHAPTER VII
Special Provisions for Radio
ARTICLE 45 (CS)
Harmful Interference
197
PP-98
1 All stations, whatever their purpose, must be established and
operated in such a manner as not to cause harmful interference to the radio
services or communications of other Member States or of recognized
operating agencies, or of other duly authorized operating agencies which
carry on a radio service, and which operate in accordance with the
provisions of the Radio Regulations.
198
PP-98
2 Each Member State undertakes to require the operating agencies
which it recognizes and the other operating agencies duly authorized for
this purpose to observe the provisions of No. 197 above.
Part A – CS 9
199PP-98
3 Further, the Member States recognize the necessity of taking all
practicable steps to prevent the operation of electrical apparatus and
installations of all kinds from causing harmful interference to the radio
services or communications mentioned in No. 197 above.
ARTICLE 46 (CS)
Distress Calls and Messages
200 Radio stations shall be obliged to accept, with absolute priority,
distress calls and messages regardless of their origin, to reply in the same
manner to such messages, and immediately to take such action in regard
thereto as may be required.
ARTICLE 47 (CS)
False or Deceptive Distress, Urgency, Safety
or Identification Signals
201
PP-98
Member States agree to take the steps required to prevent the
transmission or circulation of false or deceptive distress, urgency, safety or
identification signals, and to collaborate in locating and identifying stations
under their jurisdiction transmitting such signals.
10 Maritime Manual
ANNEX
Definition of Certain Terms Used in this Constitution,
the Convention and the Administrative Regulations
of the International Telecommunication Union
1001 For the purpose of the above instruments of the Union, the follow-
ing terms shall have the meanings defined below:
1001APP-98
Member State: A State which is considered to be a Member of
the International Telecommunication Union in application of Article 2 of
this Constitution.
1001B
PP-98
Sector Member: An entity or organization authorized in accordance
with Article 19 of the Convention to participate in the activities of a Sector.
1003 Harmful Interference: Interference which endangers the function-
ing of a radionavigation service or of other safety services or seriously
degrades, obstructs or repeatedly interrupts a radiocommunication service
operating in accordance with the Radio Regulations.
1007 Operating Agency: Any individual, company, corporation or
governmental agency which operates a telecommunication installation
intended for an international telecommunication service or capable of
causing harmful interference with such a service.
1008
PP-98
Recognized Operating Agency: Any operating agency, as defined
above, which operates a public correspondence or broadcasting service and
upon which the obligations provided for in Article 6 of this Constitution
are imposed by the Member State in whose territory the head office of the
agency is situated, or by the Member State which has authorized this
operating agency to establish and operate a telecommunication service on
its territory.
1011 International Telecommunication Service: The offering of a tele-
communication capability between telecommunication offices or stations
of any nature that are in or belong to different countries.
Part A – CS 11
1014 Government Telecommunications: Telecommunications originating
with any:
– Head of State;
– Head of government or members of a government;
– Commanders-in-Chief of military forces, land, sea or air;
– diplomatic or consular agents;
– the Secretary-General of the United Nations; Heads of the principal
organs of the United Nations;
– the International Court of Justice,
or replies to government telecommunications mentioned above.
1015 Private Telegrams: Telegrams other than government or service
telegrams.
12 Maritime Manual
CONVENTION (CV) OF THE INTERNATIONAL
TELECOMMUNICATION UNION
CHAPTER V
Various Provisions Related to the Operation
of Telecommunication Services
ARTICLE 36 (CV)
Charges and Free Services
496 The provisions regarding charges for telecommunications and the
various cases in which free services are accorded are set forth in the
Administrative Regulations.
ARTICLE 38 (CV)
Monetary Unit
500
PP-98
In the absence of special arrangements concluded between Member
States, the monetary unit to be used in the composition of accounting rates
for international telecommunication services and in the establishment of
international accounts shall be:
– either the monetary unit of the International Monetary Fund
– or the gold franc,
both as defined in the Administrative Regulations. The provisions for
application are contained in Appendix 1 to the International Telecommu-
nication Regulations.
Part A – CV 13
ARTICLE 39 (CV)
Intercommunication
501 1 Stations performing radiocommunication in the mobile service
shall be bound, within the limits of their normal employment, to exchange
radiocommunications reciprocally without distinction as to the radio
system adopted by them.
502 2 Nevertheless, in order not to impede scientific progress, the provi-
sions of No. 501 above shall not prevent the use of a radio system inca-
pable of communicating with other systems, provided that such incapacity
is due to the specific nature of such system and is not the result of devices
adopted solely with the object of preventing intercommunication.
503 3 Notwithstanding the provisions of No. 501 above, a station may be
assigned to a restricted international service of telecommunication,
determined by the purpose of such service, or by other circumstances
independent of the system used.
ARTICLE 40 (CV)
Secret Language
505
PP-98
2 Private telegrams in secret language may be admitted between all
Member States with the exception of those which have previously notified,
through the Secretary-General, that they do not admit this language for
that category of correspondence.
506
PP-98
3 Member States which do not admit private telegrams in secret
language originating in or destined for their own territory must let them
pass in transit, except in the case of suspension of service provided for in
Article 35 of the Constitution.
14 Maritime Manual
ANNEX
Definition of Certain Terms Used in this Convention and
the Administrative Regulations of the International
Telecommunication Union
For the purpose of the above instruments of the Union, the follow-
ing terms shall have the meanings defined below:
1006 Service Telecommunication: A telecommunication that relates to
public international telecommunications and that is exchanged among the
following:
– administrations,
– recognized operating agencies, and
– the Chairman of the Council, the Secretary-General, the Deputy
Secretary-General, the Directors of the Bureaux, the members of
the Radio Regulations Board, and other representatives or au-
thorized officials of the Union, including those working on official
matters outside the seat of the Union.
_______________
PART B
Extracts from the Radio Regulations (RR)
(Edition of 2008)
SECTION I – ARTICLES (Volume 1 of the RR)
SECTION II – APPENDICES (Volume 2 of the RR)
SECTION III – RESOLUTIONS (Volume 3 of the RR)
SECTION IV – ITU-R RECOMMENDATIONS INCORPORATED BY
REFERENCE (Volume 4 of the RR)
Part B 17
Note by the Secretariat
This revision of the Radio Regulations, complementing the Constitution and the
Convention of the International Telecommunication Union, incorporates the decisions
of the World Radiocommunication Conferences of 1995 (WRC-95), 1997 (WRC-97),
2000 (WRC-2000), 2003 (WRC-03) and 2007 (WRC-07). The majority of the
provisions of these Regulations entered into force as from 1 January 2009; the
remaining provisions shall apply as from the special dates of application indicated in
Article 59 of the revised Radio Regulations.
In preparing the Radio Regulations, Edition of 2008, the Secretariat corrected the
typographical errors that were drawn to the attention of WRC-07 and which were
approved by WRC-07.
This edition uses the same numbering scheme as the 2001 edition of the Radio
Regulations, notably:
With respect to Article numbers, this edition follows the standard sequential
numbering. The Article numbers are not followed by any abbreviation (such as
“(WRC-97)”, “(WRC-2000)”, “(WRC-03)” or “(WRC-07)”). Consequently, any
reference to an Article, in any of the provisions of these Radio Regulations (e.g. in
No. 13.1 of Article 13), in the texts of the Appendices as contained in Volume 2 of this
edition (e.g. in § 1 of Appendix 2), in the texts of the Resolutions included in Volume 3
of this edition (e.g. in Resolution 1 (Rev.WRC-97)), and in the texts of the
Recommendations included in Volume 3 of this edition (e.g. in Recommendation 8), is
considered as a reference to the text of the concerned Article which appears in this
edition, unless otherwise specified.
With respect to provision numbers in Articles, this edition continues to use composite
numbers indicating the number of the Article and the provision number within that
Article (e.g. No. 9.2B means provision No. 2B of Article 9). The abbreviation
“(WRC-07)”, “(WRC-03)”, “(WRC-2000)” or “(WRC-97)” at the end of such a
provision means that the relevant provision was modified or added by WRC-07, by
WRC-03, by WRC-2000 or by WRC-97, as applicable. The absence of an abbreviation
at the end of the provision means that the provision is identical with the provision of the
simplified Radio Regulations as approved by WRC-95, and whose complete text was
contained in Document 2 of WRC-97.
18 Maritime Manual
With respect to Appendix numbers, this edition follows the standard sequential
numbering, with the addition of the appropriate abbreviation after the Appendix number
(such as “(WRC-97)”, “(WRC-2000)”, “(WRC-03)” or “(WRC-07)”), where
applicable. As a rule, any reference to an Appendix, in any of the provisions of these
Radio Regulations, in the texts of the Appendices as contained in Volume 2 of this
edition, in the texts of the Resolutions and of the Recommendations included in
Volume 3 of this edition, is presented in the standard manner (e.g. “Appendix 30
(Rev.WRC-07)”) if not explicitly described in the text (e.g. Appendix 4 as modified by
WRC-07). In the texts of Appendices that were partially modified by WRC-07, the
provisions that were modified by WRC-07 are indicated with the abbreviation
“(WRC-07)” at the end of the concerned text. If an Appendix is referenced without any
abbreviation after the Appendix number, in the texts of this edition (e.g., in No. 13.1),
or without other description, such reference is considered as a reference to the text of
the concerned Appendix which appears in this edition.
Abbreviations have generally been used for the names of world administrative radio
conferences and world radiocommunication conferences. These abbreviations are
shown below.
Part B 19
_______________
1 The date of this conference has not been finalized.
Abbreviation Conference
WARC Mar World Administrative Radio Conference to Deal with Matters Relating
to the Maritime Mobile Service (Geneva, 1967)
WARC-71 World Administrative Radio Conference for Space Telecommuni-
cations (Geneva, 1971)
WMARC-74 World Maritime Administrative Radio Conference (Geneva, 1974)
WARC SAT-77 World Broadcasting-Satellite Administrative Radio Conference
(Geneva, 1977)
WARC-Aer2 World Administrative Radio Conference on the Aeronautical Mobile
(R) Service (Geneva, 1978)
WARC-79 World Administrative Radio Conference (Geneva, 1979)
WARC Mob-83 World Administrative Radio Conference for the Mobile Services
(Geneva, 1983)
WARC HFBC-84 World Administrative Radio Conference for the Planning of the HF
Bands Allocated to the Broadcasting Service (Geneva, 1984)
WARC Orb-85 World Administrative Radio Conference on the Use of the
Geostationary-Satellite Orbit and the Planning of Space Services
Utilising It (First Session – Geneva, 1985)
WARC HFBC-87 World Administrative Radio Conference for the Planning of the HF
Bands Allocated to the Broadcasting Service (Geneva, 1987)
WARC Mob-87 World Administrative Radio Conference for the Mobile Services
(Geneva, 1987)
WARC Orb-88 World Administrative Radio Conference on the Use of the
Geostationary-Satellite Orbit and the Planning of Space Services
Utilising It (Second Session – Geneva, 1988)
WARC-92 World Administrative Radio Conference for Dealing with Frequency
Allocations in Certain Parts of the Spectrum (Malaga-Torremolinos,
1992)
WRC-95 World Radiocommunication Conference (Geneva, 1995)
WRC-97 World Radiocommunication Conference (Geneva, 1997)
WRC-2000 World Radiocommunication Conference (Istanbul, 2000)
WRC-03 World Radiocommunication Conference, (Geneva, 2003)
WRC-07 World Radiocommunication Conference, (Geneva, 2007)
WRC-12 World Radiocommunication Conference, 2012
WRC-15 World Radiocommunication Conference, 20151
SECTION I
Articles
(Extracts)
Part B – SECTION I – RR1 23
ARTICLE 1
Terms and definitions
Introduction
1.1 For the purposes of these Regulations, the following terms shall have the
meanings defined below. These terms and definitions do not, however, necessarily
apply for other purposes. Definitions identical to those contained in the Annex to the
Constitution or the Annex to the Convention of the International Telecommunication
Union (Geneva, 1992) are marked “(CS)” or “(CV)” respectively.
NOTE – If, in the text of a definition below, a term is printed in italics, this means that the term
itself is defined in this Article.
Section I – General terms
1.2 administration: Any governmental department or service responsible for
discharging the obligations undertaken in the Constitution of the International Telecom-
munication Union, in the Convention of the International Telecommunication Union
and in the Administrative Regulations (CS 1002).
1.3 telecommunication: Any transmission, emission or reception of signs,
signals, writings, images and sounds or intelligence of any nature by wire, radio, optical
or other electromagnetic systems (CS).
1.4 radio: A general term applied to the use of radio waves.
1.5 radio waves or hertzian waves: Electromagnetic waves of frequencies
arbitrarily lower than 3 000 GHz, propagated in space without artificial guide.
1.6 radiocommunication: Telecommunication by means of radio waves (CS)
(CV).
1.7 terrestrial radiocommunication: Any radiocommunication other than
space radiocommunication or radio astronomy.
1.8 space radiocommunication: Any radiocommunication involving the use
of one or more space stations or the use of one or more reflecting satellites or other
objects in space.
24 Maritime Manual
1.9 radiodetermination: The determination of the position, velocity and/or
other characteristics of an object, or the obtaining of information relating to these
parameters, by means of the propagation properties of radio waves.
1.10 radionavigation: Radiodetermination used for the purposes of navigation,
including obstruction warning.
1.11 radiolocation: Radiodetermination used for purposes other than those of
radionavigation.
1.12 radio direction-finding: Radiodetermination using the reception of radio
waves for the purpose of determining the direction of a station or object.
1.13 radio astronomy: Astronomy based on the reception of radio waves of
cosmic origin.
1.14 Coordinated Universal Time (UTC): Time scale, based on the second
(SI), as defined in Recommendation ITU-R TF.460-6. (WRC-03)
For most practical purposes associated with the Radio Regulations, UTC
is equivalent to mean solar time at the prime meridian (0° longitude), formerly
expressed in GMT.
1.15 industrial, scientific and medical (ISM) applications (of radio frequency
energy): Operation of equipment or appliances designed to generate and use locally
radio frequency energy for industrial, scientific, medical, domestic or similar purposes,
excluding applications in the field of telecommunications.
Section II – Specific terms related to frequency management
1.16 allocation (of a frequency band): Entry in the Table of Frequency
Allocations of a given frequency band for the purpose of its use by one or more
terrestrial or space radiocommunication services or the radio astronomy service under
specified conditions. This term shall also be applied to the frequency band concerned.
1.17 allotment (of a radio frequency or radio frequency channel): Entry of a
designated frequency channel in an agreed plan, adopted by a competent conference,
for use by one or more administrations for a terrestrial or space radiocommunication
service in one or more identified countries or geographical areas and under specified
conditions.
Part B – SECTION I – RR1 25
1.18 assignment (of a radio frequency or radio frequency
channel): Authorization given by an administration for a radio station to use a radio
frequency or radio frequency channel under specified conditions.
Section III – Radio services
1.19 radiocommunication service: A service as defined in this Section
involving the transmission, emission and/or reception of radio waves for specific
telecommunication purposes.
In these Regulations, unless otherwise stated, any radiocommunication
service relates to terrestrial radiocommunication.
1.20 fixed service: A radiocommunication service between specified fixed
points.
1.21 fixed-satellite service: A radiocommunication service between earth
stations at given positions, when one or more satellites are used; the given position may
be a specified fixed point or any fixed point within specified areas; in some cases this
service includes satellite-to-satellite links, which may also be operated in the inter-
satellite service; the fixed-satellite service may also include feeder links for other space
radiocommunication services.
1.22 inter-satellite service: A radiocommunication service providing links
between artificial satellites.
1.23 space operation service: A radiocommunication service concerned
exclusively with the operation of spacecraft, in particular space tracking, space
telemetry and space telecommand.
These functions will normally be provided within the service in which the
space station is operating.
1.24 mobile service: A radiocommunication service between mobile and land
stations, or between mobile stations (CV).
1.25 mobile-satellite service: A radiocommunication service:
– between mobile earth stations and one or more space stations, or between
space stations used by this service; or
– between mobile earth stations by means of one or more space stations.
This service may also include feeder links necessary for its operation.
1.26 land mobile service: A mobile service between base stations and land
mobile stations, or between land mobile stations.
26 Maritime Manual
1.27 land mobile-satellite service: A mobile-satellite service in which mobile
earth stations are located on land.
1.28 maritime mobile service: A mobile service between coast stations and
ship stations, or between ship stations, or between associated on-board communication
stations; survival craft stations and emergency position-indicating radiobeacon stations
may also participate in this service.
1.29 maritime mobile-satellite service: A mobile-satellite service in which
mobile earth stations are located on board ships; survival craft stations and emergency
position-indicating radiobeacon stations may also participate in this service.
1.30 port operations service: A maritime mobile service in or near a port,
between coast stations and ship stations, or between ship stations, in which messages
are restricted to those relating to the operational handling, the movement and the safety
of ships and, in emergency, to the safety of persons.
Messages which are of a public correspondence nature shall be excluded
from this service.
1.31 ship movement service: A safety service in the maritime mobile service
other than a port operations service, between coast stations and ship stations, or
between ship stations, in which messages are restricted to those relating to the
movement of ships.
Messages which are of a public correspondence nature shall be excluded
from this service.
1.32 aeronautical mobile service: A mobile service between aeronautical
stations and aircraft stations, or between aircraft stations, in which survival craft
stations may participate; emergency position-indicating radiobeacon stations may also
participate in this service on designated distress and emergency frequencies.
1.33 aeronautical mobile (R)* service: An aeronautical mobile service
reserved for communications relating to safety and regularity of flight, primarily along
national or international civil air routes.
1.34 aeronautical mobile (OR)** service: An aeronautical mobile service
intended for communications, including those relating to flight coordination, primarily
outside national or international civil air routes.
_______________
* (R): route.
** (OR): off-route.
Part B – SECTION I – RR1 27
1.35 aeronautical mobile-satellite service: A mobile-satellite service in which
mobile earth stations are located on board aircraft; survival craft stations and
emergency position-indicating radiobeacon stations may also participate in this service.
1.36 aeronautical mobile-satellite (R)* service: An aeronautical mobile-
satellite service reserved for communications relating to safety and regularity of flights,
primarily along national or international civil air routes.
1.37 aeronautical mobile-satellite (OR)** service: An aeronautical mobile-
satellite service intended for communications, including those relating to flight
coordination, primarily outside national and international civil air routes.
1.38 broadcasting service: A radiocommunication service in which the
transmissions are intended for direct reception by the general public. This service may
include sound transmissions, television transmissions or other types of transmission
(CS).
1.39 broadcasting-satellite service: A radiocommunication service in which
signals transmitted or retransmitted by space stations are intended for direct reception
by the general public.
In the broadcasting-satellite service, the term “direct reception” shall
encompass both individual reception and community reception.
1.40 radiodetermination service: A radiocommunication service for the
purpose of radiodetermination.
1.41 radiodetermination-satellite service: A radiocommunication service for
the purpose of radiodetermination involving the use of one or more space stations.
This service may also include feeder links necessary for its own operation.
1.42 radionavigation service: A radiodetermination service for the purpose of
radionavigation.
1.43 radionavigation-satellite service: A radiodetermination-satellite service
used for the purpose of radionavigation.
This service may also include feeder links necessary for its operation.
1.44 maritime radionavigation service: A radionavigation service intended for
the benefit and for the safe operation of ships.
1.45 maritime radionavigation-satellite service: A radionavigation-satellite
service in which earth stations are located on board ships.
28 Maritime Manual
1.46 aeronautical radionavigation service: A radionavigation service
intended for the benefit and for the safe operation of aircraft.
1.47 aeronautical radionavigation-satellite service: A radionavigation-
satellite service in which earth stations are located on board aircraft.
1.48 radiolocation service: A radiodetermination service for the purpose of
radiolocation.
1.49 radiolocation-satellite service: A radiodetermination-satellite service
used for the purpose of radiolocation.
This service may also include the feeder links necessary for its operation.
1.50 meteorological aids service: A radiocommunication service used for
meteorological, including hydrological, observations and exploration.
1.51 Earth exploration-satellite service: A radiocommunication service
between earth stations and one or more space stations, which may include links
between space stations, in which:
– information relating to the characteristics of the Earth and its natural
phenomena, including data relating to the state of the environment, is obtained
from active sensors or passive sensors on Earth satellites;
– similar information is collected from airborne or Earth-based platforms;
– such information may be distributed to earth stations within the system
concerned;
– platform interrogation may be included.
This service may also include feeder links necessary for its operation.
1.52 meteorological-satellite service: An earth exploration-satellite service
for meteorological purposes.
1.53 standard frequency and time signal service: A radiocommunication
service for scientific, technical and other purposes, providing the transmission of
specified frequencies, time signals, or both, of stated high precision, intended for
general reception.
1.54 standard frequency and time signal-satellite service: A
radiocommunication service using space stations on earth satellites for the same
purposes as those of the standard frequency and time signal service.
This service may also include feeder links necessary for its operation.
Part B – SECTION I – RR1 29
1.55 space research service: A radiocommunication service in which
spacecraft or other objects in space are used for scientific or technological research
purposes.
1.56 amateur service: A radiocommunication service for the purpose of self-
training, intercommunication and technical investigations carried out by amateurs, that
is, by duly authorized persons interested in radio technique solely with a personal aim
and without pecuniary interest.
1.57 amateur-satellite service: A radiocommunication service using space
stations on earth satellites for the same purposes as those of the amateur service.
1.58 radio astronomy service: A service involving the use of radio astronomy.
1.59 safety service: Any radiocommunication service used permanently or
temporarily for the safeguarding of human life and property.
1.60 special service: A radiocommunication service, not otherwise defined in
this Section, carried on exclusively for specific needs of general utility, and not open to
public correspondence.
Section IV – Radio stations and systems
1.61 station: One or more transmitters or receivers or a combination of
transmitters and receivers, including the accessory equipment, necessary at one location
for carrying on a radiocommunication service, or the radio astronomy service.
Each station shall be classified by the service in which it operates
permanently or temporarily.
1.62 terrestrial station: A station effecting terrestrial radiocommunication.
In these Regulations, unless otherwise stated, any station is a terrestrial
station.
1.63 earth station: A station located either on the Earth's surface or within the
major portion of the Earth's atmosphere and intended for communication:
– with one or more space stations; or
– with one or more stations of the same kind by means of one or more
reflecting satellites or other objects in space.
1.64 space station: A station located on an object which is beyond, is intended
to go beyond, or has been beyond, the major portion of the Earth's atmosphere.
30 Maritime Manual
1.65 survival craft station: A mobile station in the maritime mobile service or
the aeronautical mobile service intended solely for survival purposes and located on
any lifeboat, life-raft or other survival equipment.
1.66 fixed station: A station in the fixed service.
1.66A high altitude platform station: A station located on an object at an
altitude of 20 to 50 km and at a specified, nominal, fixed point relative to the Earth.
1.67 mobile station: A station in the mobile service intended to be used while
in motion or during halts at unspecified points.
1.68 mobile earth station: An earth station in the mobile-satellite service
intended to be used while in motion or during halts at unspecified points.
1.69 land station: A station in the mobile service not intended to be used while
in motion.
1.70 land earth station: An earth station in the fixed-satellite service or, in
some cases, in the mobile-satellite service, located at a specified fixed point or within a
specified area on land to provide a feeder link for the mobile-satellite service.
1.71 base station: A land station in the land mobile service.
1.72 base earth station: An earth station in the fixed-satellite service or, in
some cases, in the land mobile-satellite service, located at a specified fixed point or
within a specified area on land to provide a feeder link for the land mobile-satellite
service.
1.73 land mobile station: A mobile station in the land mobile service capable
of surface movement within the geographical limits of a country or continent.
1.74 land mobile earth station: A mobile earth station in the land
mobile-satellite service capable of surface movement within the geographical limits of a
country or continent.
1.75 coast station: A land station in the maritime mobile service.
1.76 coast earth station: An earth station in the fixed-satellite service or, in
some cases, in the maritime mobile-satellite service, located at a specified fixed point
on land to provide a feeder link for the maritime mobile-satellite service.
1.77 ship station: A mobile station in the maritime mobile service located on
board a vessel which is not permanently moored, other than a survival craft station.
Part B – SECTION I – RR1 31
1.78 ship earth station: A mobile earth station in the maritime mobile-satellite
service located on board ship.
1.79 on-board communication station: A low-powered mobile station in the
maritime mobile service intended for use for internal communications on board a ship,
or between a ship and its lifeboats and life-rafts during lifeboat drills or operations, or
for communication within a group of vessels being towed or pushed, as well as for line
handling and mooring instructions.
1.80 port station: A coast station in the port operations service.
1.81 aeronautical station: A land station in the aeronautical mobile service.
In certain instances, an aeronautical station may be located, for example,
on board ship or on a platform at sea.
1.82 aeronautical earth station: An earth station in the fixed-satellite service,
or, in some cases, in the aeronautical mobile-satellite service, located at a specified
fixed point on land to provide a feeder link for the aeronautical mobile-satellite service.
1.83 aircraft station: A mobile station in the aeronautical mobile service,
other than a survival craft station, located on board an aircraft.
1.84 aircraft earth station: A mobile earth station in the aeronautical mobile-
satellite service located on board an aircraft.
1.85 broadcasting station: A station in the broadcasting service.
1.86 radiodetermination Station: A station in the radiodetermination service.
1.87 radionavigation mobile station: A station in the radionavigation service
intended to be used while in motion or during halts at unspecified points.
1.88 radionavigation land station: A station in the radionavigation service not
intended to be used while in motion.
1.89 radiolocation mobile station: A station in the radiolocation service
intended to be used while in motion or during halts at unspecified points.
1.90 radiolocation land station: A station in the radiolocation service not
intended to be used while in motion.
1.91 radio direction-finding station: A radiodetermination station using radio
direction-finding.
1.92 radiobeacon station: A station in the radionavigation service the
emissions of which are intended to enable a mobile station to determine its bearing or
direction in relation to the radiobeacon station.
32 Maritime Manual
1.93 emergency position-indicating radiobeacon station: A station in the
mobile service the emissions of which are intended to facilitate search and rescue
operations.
1.94 satellite emergency position-indicating radiobeacon: An earth station in
the mobile-satellite service the emissions of which are intended to facilitate search and
rescue operations.
1.95 standard frequency and time signal station: A station in the standard
frequency and time signal service.
1.96 amateur station: A station in the amateur service.
1.97 radio astronomy station: A station in the radio astronomy service.
1.98 experimental station: A station utilizing radio waves in experiments with
a view to the development of science or technique.
This definition does not include amateur stations.
1.99 ship's emergency transmitter: A ship's transmitter to be used exclusively
on a distress frequency for distress, urgency or safety purposes.
1.100 radar: A radiodetermination system based on the comparison of
reference signals with radio signals reflected, or retransmitted, from the position to be
determined.
1.101 primary radar: A radiodetermination system based on the comparison of
reference signals with radio signals reflected from the position to be determined.
1.102 secondary radar: A radiodetermination system based on the comparison
of reference signals with radio signals retransmitted from the position to be determined.
1.103 radar beacon (racon): A transmitter-receiver associated with a fixed
navigational mark which, when triggered by a radar, automatically returns a distinctive
signal which can appear on the display of the triggering radar, providing range, bearing
and identification information.
1.104 instrument landing system (ILS): A radionavigation system which
provides aircraft with horizontal and vertical guidance just before and during landing
and, at certain fixed points, indicates the distance to the reference point of landing.
1.105 instrument landing system localizer: A system of horizontal guidance
embodied in the instrument landing system which indicates the horizontal deviation of
the aircraft from its optimum path of descent along the axis of the runway.
Part B – SECTION I – RR1 33
1.106 instrument landing system glide path: A system of vertical guidance
embodied in the instrument landing system which indicates the vertical deviation of the
aircraft from its optimum path of descent.
1.107 marker beacon: A transmitter in the aeronautical radionavigation service
which radiates vertically a distinctive pattern for providing position information to
aircraft.
1.108 radio altimeter: Radionavigation equipment, on board an aircraft or
spacecraft, used to determine the height of the aircraft or the spacecraft above the
Earth's surface or another surface.
1.109 radiosonde: An automatic radio transmitter in the meteorological aids
service usually carried on an aircraft, free balloon, kite or parachute, and which
transmits meteorological data.
1.109A adaptive system: A radiocommunication system which varies its radio
characteristics according to channel quality.
1.110 space system: Any group of cooperating earth stations and/or space
stations employing space radiocommunication for specific purposes.
1.111 satellite system: A space system using one or more artificial earth
satellites.
1.112 satellite network: A satellite system or a part of a satellite system,
consisting of only one satellite and the cooperating earth stations.
1.113 satellite link: A radio link between a transmitting earth station and a
receiving earth station through one satellite.
A satellite link comprises one up-link and one down-link.
1.114 multi-satellite link: A radio link between a transmitting earth station and
a receiving earth station through two or more satellites, without any intermediate earth
station.
A multi-satellite link comprises one up-link, one or more satellite-to-
satellite links and one down-link.
1.115 feeder link: A radio link from an earth station at a given location to a
space station, or vice versa, conveying information for a space radiocommunication
service other than for the fixed-satellite service. The given location may be at a
specified fixed point, or at any fixed point within specified areas.
34 Maritime Manual
Section V – Operational terms
1.116 public correspondence: Any telecommunication which the offices and
stations must, by reason of their being at the disposal of the public, accept for
transmission (CS).
1.117 telegraphy1: A form of telecommunication in which the transmitted
information is intended to be recorded on arrival as a graphic document; the transmitted
information may sometimes be presented in an alternative form or may be stored for
subsequent use (CS 1016).
1.118 telegram: Written matter intended to be transmitted by telegraphy for
delivery to the addressee. This term also includes radiotelegrams unless otherwise
specified (CS).
In this definition the term telegraphy has the same general meaning as
defined in the Convention.
1.119 radiotelegram: A telegram, originating in or intended for a mobile station
or a mobile earth station transmitted on all or part of its route over the
radiocommunication channels of the mobile service or of the mobile-satellite service.
1.120 radiotelex call: A telex call, originating in or intended for a mobile
station or a mobile earth station, transmitted on all or part of its route over the
radiocommunication channels of the mobile service or the mobile-satellite service.
1.121 frequency-shift telegraphy: Telegraphy by frequency modulation in
which the telegraph signal shifts the frequency of the carrier between predetermined
values.
1.122 facsimile: A form of telegraphy for the transmission of fixed images,
with or without half-tones, with a view to their reproduction in a permanent form.
1.123 telephony: A form of telecommunication primarily intended for the
exchange of information in the form of speech (CS 1017).
_______________
1 1.117.1 A graphic document records information in a permanent form and is capable of
being filed and consulted; it may take the form of written or printed matter or of a fixed image.
Part B – SECTION I – RR1 35
1.124 radiotelephone call: A telephone call, originating in or intended for a
mobile station or a mobile earth station, transmitted on all or part of its route over the
radiocommunication channels of the mobile service or of the mobile-satellite service.
1.125 simplex operation: Operating method in which transmission is made
possible alternately in each direction of a telecommunication channel, for example, by
means of manual control2.
1.126 duplex operation: Operating method in which transmission is possible
simultaneously in both directions of a telecommunication channel2.
1.127 semi-duplex operation: A method which is simplex operation at one end
of the circuit and duplex operation at the other.2
1.128 television: A form of telecommunication for the transmission of transient
images of fixed or moving objects.
1.129 individual reception (in the broadcasting-satellite service): The reception
of emissions from a space station in the broadcasting-satellite service by simple
domestic installations and in particular those possessing small antennas.
1.130 community reception (in the broadcasting-satellite service): The reception
of emissions from a space station in the broadcasting-satellite service by receiving
equipment, which in some cases may be complex and have antennas larger than those
used for individual reception, and intended for use:
– by a group of the general public at one location; or
– through a distribution system covering a limited area.
1.131 telemetry: The use of telecommunication for automatically indicating or
recording measurements at a distance from the measuring instrument.
1.132 radiotelemetry: Telemetry by means of radio waves.
1.133 space telemetry: The use of telemetry for the transmission from a space
station of results of measurements made in a spacecraft, including those relating to the
functioning of the spacecraft.
1.134 telecommand: The use of telecommunication for the transmission of
signals to initiate, modify or terminate functions of equipment at a distance.
_______________
2 1.125.1, 1.126.1 and 1.127.1 In general, duplex operation and semi-duplex operation
require two frequencies in radiocommunication; simplex operation may use either one or two.
36 Maritime Manual
1.135 space telecommand: The use of radiocommunication for the transmission
of signals to a space station to initiate, modify or terminate functions of equipment on
an associated space object, including the space station.
1.136 space tracking: Determination of the orbit, velocity or instantaneous
position of an object in space by means of radiodetermination, excluding primary
radar, for the purpose of following the movement of the object.
Section VI – Characteristics of emissions and radio equipment
1.137 radiation: The outward flow of energy from any source in the form of
radio waves.
1.138 emission: Radiation produced, or the production of radiation, by a radio
transmitting station.
For example, the energy radiated by the local oscillator of a radio receiver
would not be an emission but a radiation.
1.139 class of emission: The set of characteristics of an emission, designated by
standard symbols, e.g. type of modulation of the main carrier, modulating signal, type
of information to be transmitted, and also, if appropriate, any additional signal
characteristics.
1.140 single-sideband emission: An amplitude modulated emission with one
sideband only.
1.141 full carrier single-sideband emission: A single-sideband emission
without reduction of the carrier.
1.142 reduced carrier single-sideband emission: A single-sideband emission in
which the degree of carrier suppression enables the carrier to be reconstituted and to be
used for demodulation.
1.143 suppressed carrier single-sideband emission: A single-sideband emission
in which the carrier is virtually suppressed and not intended to be used for
demodulation.
Part B – SECTION I – RR1 37
1.144 out-of-band emission*: Emission on a frequency or frequencies
immediately outside the necessary bandwidth which results from the modulation
process, but excluding spurious emissions.
1.145 spurious emission*: Emission on a frequency or frequencies which are
outside the necessary bandwidth and the level of which may be reduced without
affecting the corresponding transmission of information. Spurious emissions include
harmonic emissions, parasitic emissions, intermodulation products and frequency
conversion products, but exclude out-of-band emissions.
1.146 unwanted emissions*: Consist of spurious emissions and out-of-band
emissions.
1.146A out-of-band domain (of an emission): The frequency range, immediately
outside the necessary bandwidth but excluding the spurious domain, in which out-of-
band emissions generally predominate. Out-of-band emissions, defined based on their
source, occur in the out-of-band domain and, to a lesser extent, in the spurious domain.
Spurious emissions likewise may occur in the out-of-band domain as well as in the
spurious domain. (WRC-03)
1.146B spurious domain (of an emission): The frequency range beyond the out-
of-band domain in which spurious emissions generally predominate. (WRC-03)
1.147 assigned frequency band: The frequency band within which the emission
of a station is authorized; the width of the band equals the necessary bandwidth plus
twice the absolute value of the frequency tolerance. Where space stations are
concerned, the assigned frequency band includes twice the maximum Doppler shift that
may occur in relation to any point of the Earth’s surface.
_______________
* The terms associated with the definitions given by Nos. 1.144, 1.145 and 1.146 shall be
expressed in the working languages as follows:
Numbers In French In English In Spanish
1.144 Emission hors bande Out-of-band emission Emisión fuera de banda
1.145 Rayonnement non essentiel Spurious emission Emisión no esencial
1.146 Rayonnements non désirés Unwanted emissions Emisiones no deseadas
38 Maritime Manual
1.148 assigned frequency: The centre of the frequency band assigned to a
station.
1.149 characteristic frequency: A frequency which can be easily identified and
measured in a given emission.
A carrier frequency may, for example, be designated as the characteristic
frequency.
1.150 reference frequency: A frequency having a fixed and specified position
with respect to the assigned frequency. The displacement of this frequency with respect
to the assigned frequency has the same absolute value and sign that the displacement of
the characteristic frequency has with respect to the centre of the frequency band
occupied by the emission.
1.151 frequency tolerance: The maximum permissible departure by the centre
frequency of the frequency band occupied by an emission from the assigned frequency
or, by the characteristic frequency of an emission from the reference frequency.
The frequency tolerance is expressed in parts in 106 or in hertz.
1.152 necessary bandwidth: For a given class of emission, the width of the
frequency band which is just sufficient to ensure the transmission of information at the
rate and with the quality required under specified conditions.
1.153 occupied bandwidth: The width of a frequency band such that, below the
lower and above the upper frequency limits, the mean powers emitted are each equal to
a specified percentage β/2 of the total mean power of a given emission.
Unless otherwise specified in an ITU-R Recommendation for the
appropriate class of emission, the value of β/2 should be taken as 0.5%.
1.154 right-hand (clockwise) polarized wave: An elliptically- or circularly-
polarized wave, in which the electric field vector, observed in any fixed plane, normal
to the direction of propagation, whilst looking in the direction of propagation, rotates
with time in a right-hand or clockwise direction.
1.155 left-hand (anticlockwise) polarized wave: An elliptically- or circularly-
polarized wave, in which the electric field vector, observed in any fixed plane, normal
to the direction of propagation, whilst looking in the direction of propagation, rotates
with time in a left-hand or anticlockwise direction.
Part B – SECTION I – RR1 39
1.156 power: Whenever the power of a radio transmitter, etc. is referred to it
shall be expressed in one of the following forms, according to the class of emission,
using the arbitrary symbols indicated:
– peak envelope power (PX or pX);
– mean power (PY or pY);
– carrier power (PZ or pZ).
For different classes of emission, the relationships between peak envelope
power, mean power and carrier power, under the conditions of normal operation and of
no modulation, are contained in ITU-R Recommendations which may be used as a
guide.
For use in formulae, the symbol p denotes power expressed in watts and
the symbol P denotes power expressed in decibels relative to a reference level.
1.157 peak envelope power (of a radio transmitter): The average power
supplied to the antenna transmission line by a transmitter during one radio frequency
cycle at the crest of the modulation envelope taken under normal operating conditions.
1.158 mean power (of a radio transmitter): The average power supplied to the
antenna transmission line by a transmitter during an interval of time sufficiently long
compared with the lowest frequency encountered in the modulation taken under normal
operating conditions.
1.159 carrier power (of a radio transmitter): The average power supplied to the
antenna transmission line by a transmitter during one radio frequency cycle taken under
the condition of no modulation.
1.160 gain of an antenna: The ratio, usually expressed in decibels, of the power
required at the input of a loss-free reference antenna to the power supplied to the input
of the given antenna to produce, in a given direction, the same field strength or the
same power flux-density at the same distance. When not specified otherwise, the gain
refers to the direction of maximum radiation. The gain may be considered for a
specified polarization.
Depending on the choice of the reference antenna a distinction is made
between:
a) absolute or isotropic gain (Gi), when the reference antenna is an isotropic
antenna isolated in space;
b) gain relative to a half-wave dipole (Gd), when the reference antenna is a
half-wave dipole isolated in space whose equatorial plane contains the given
direction;
40 Maritime Manual
c) gain relative to a short vertical antenna (Gv), when the reference antenna
is a linear conductor, much shorter than one quarter of the wavelength, normal
to the surface of a perfectly conducting plane which contains the given
direction.
1.161 equivalent isotropically radiated power (e.i.r.p.): The product of the
power supplied to the antenna and the antenna gain in a given direction relative to an
isotropic antenna (absolute or isotropic gain).
1.162 effective radiated power (e.r.p.) (in a given direction): The product of the
power supplied to the antenna and its gain relative to a half-wave dipole in a given
direction.
1.163 effective monopole radiated power (e.m.r.p.) (in a given direction): The
product of the power supplied to the antenna and its gain relative to a short vertical
antenna in a given direction.
1.164 tropospheric scatter: The propagation of radio waves by scattering as a
result of irregularities or discontinuities in the physical properties of the troposphere.
1.165 ionospheric scatter: The propagation of radio waves by scattering as a
result of irregularities or discontinuities in the ionization of the ionosphere.
Section VII – Frequency sharing
1.166 interference: The effect of unwanted energy due to one or a combination
of emissions, radiations, or inductions upon reception in a radiocommunication system,
manifested by any performance degradation, misinterpretation, or loss of information
which could be extracted in the absence of such unwanted energy.
1.167 permissible interference3: Observed or predicted interference which
complies with quantitative interference and sharing criteria contained in these
Regulations or in ITU-R Recommendations or in special agreements as provided for in
these Regulations.
1.168 accepted interference3: Interference at a higher level than that defined as
permissible interference and which has been agreed upon between two or more
administrations without prejudice to other administrations.
_______________
3 1.167.1 and 1.168.1 The terms “permissible interference” and “accepted interference” are
used in the coordination of frequency assignments between administrations.
Part B – SECTION I – RR1 41
1.169 harmful interference: Interference which endangers the functioning of a
radionavigation service or of other safety services or seriously degrades, obstructs, or
repeatedly interrupts a radiocommunication service operating in accordance with Radio
Regulations (CS).
1.170 protection ratio (R.F.): The minimum value of the wanted-to-unwanted
signal ratio, usually expressed in decibels, at the receiver input, determined under
specified conditions such that a specified reception quality of the wanted signal is
achieved at the receiver output.
1.171 coordination area: When determining the need for coordination, the area
surrounding an earth station sharing the same frequency band with terrestrial stations,
or surrounding a transmitting earth station sharing the same bidirectionally allocated
frequency band with receiving earth stations, beyond which the level of permissible
interference will not be exceeded and coordination is therefore not
required. (WRC-2000)
1.172 coordination contour: The line enclosing the coordination area.
1.173 coordination distance: When determining the need for coordination, the
distance on a given azimuth from an earth station sharing the same frequency band
with terrestrial stations, or from a transmitting earth station sharing the same
bidirectionally allocated frequency band with receiving earth stations, beyond which
the level of permissible interference will not be exceeded and coordination is therefore
not required. (WRC-2000)
1.174 equivalent satellite link noise temperature: The noise temperature
referred to the output of the receiving antenna of the earth station corresponding to the
radio frequency noise power which produces the total observed noise at the output of
the satellite link excluding noise due to interference coming from satellite links using
other satellites and from terrestrial systems.
1.175 effective boresight area (of a steerable satellite beam): An area on the
surface of the Earth within which the boresight of a steerable satellite beam is intended
to be pointed.
There may be more than one unconnected effective boresight area to
which a single steerable satellite beam is intended to be pointed.
1.176 effective antenna gain contour (of a steerable satellite beam): An
envelope of antenna gain contours resulting from moving the boresight of a steerable
satellite beam along the limits of the effective boresight area.
42 Maritime Manual
Section VIII – Technical terms relating to space
1.177 deep space: Space at distances from the Earth equal to, or greater than,
2 × 106 km.
1.178 spacecraft: A man-made vehicle which is intended to go beyond the
major portion of the Earth's atmosphere.
1.179 satellite: A body which revolves around another body of preponderant
mass and which has a motion primarily and permanently determined by the force of
attraction of that other body.
1.180 active satellite: A satellite carrying a station intended to transmit or
retransmit radiocommunication signals.
1.181 reflecting satellite: A satellite intended to reflect radiocommunication
signals.
1.182 active sensor: A measuring instrument in the earth exploration-satellite
service or in the space research service by means of which information is obtained by
transmission and reception of radio waves.
1.183 passive sensor: A measuring instrument in the earth exploration-satellite
service or in the space research service by means of which information is obtained by
reception of radio waves of natural origin.
1.184 orbit: The path, relative to a specified frame of reference, described by
the centre of mass of a satellite or other object in space subjected primarily to natural
forces, mainly the force of gravity.
1.185 inclination of an orbit (of an earth satellite): The angle determined by the
plane containing the orbit and the plane of the Earth’s equator measured in degrees
between 0º and 180º and in counter-clockwise direction from the Earth’s equatorial
plane at the ascending node of the orbit. (WRC-2000)
1.186 period (of a satellite): The time elapsing between two consecutive
passages of a satellite through a characteristic point on its orbit.
1.187 altitude of the apogee or of the perigee: The altitude of the apogee or
perigee above a specified reference surface serving to represent the surface of the Earth.
1.188 geosynchronous satellite: An earth satellite whose period of revolution is
equal to the period of rotation of the Earth about its axis.
Part B – SECTION I – RR1 43
1.189 geostationary satellite: A geosynchronous satellite whose circular and
direct orbit lies in the plane of the Earth’s equator and which thus remains fixed relative
to the Earth; by extension, a geosynchronous satellite which remains approximately
fixed relative to the Earth. (WRC-03)
1.190 geostationary-satellite orbit: The orbit of a geosynchronous satellite
whose circular and direct orbit lies in the plane of the Earth's equator.
1.191 steerable satellite beam: A satellite antenna beam that can be re-pointed.
44 Maritime Manual
ARTICLE 2
Nomenclature
Section I – Frequency and wavelength bands
2.1 The radio spectrum shall be subdivided into nine frequency bands, which
shall be designated by progressive whole numbers in accordance with the following
table. As the unit of frequency is the hertz (Hz), frequencies shall be expressed:
– in kilohertz (kHz), up to and including 3 000 kHz;
– in megahertz (MHz), above 3 MHz, up to and including 3000 MHz;
– in gigahertz (GHz), above 3 GHz, up to and including 3 000 GHz.
However, where adherence to these provisions would introduce serious
difficulties, for example in connection with the notification and registration of
frequencies, the lists of frequencies and related matters, reasonable departures may be
made1. (WRC-07)
_______________
1 2.1.1 In the application of the Radio Regulations, the Radiocommunication Bureau uses the
following units:
kHz for frequencies up to 28 000 kHz inclusive
MHz for frequencies above 28 000 kHz up to 10 500 MHz inclusive
GHz for frequencies above 10 500 MHz.
Part B – SECTION I – RR2 45
2.2 In communications between administrations and the ITU, no names,
symbols or abbreviations should be used for the various frequency bands other than
those specified in No. 2.1.
Section II – Dates and times
2.3 Any date used in relation to radiocommunication shall be according to the
Gregorian Calendar.
2.4 If in a date the month is not indicated either in full or in an abbreviated
form, it shall be expressed in an all-numeric form with the fixed sequence of figures,
two of each representing the day, month and year.
2.5 Whenever a date is used in connection with Coordinated Universal Time
(UTC), this date shall be that of the prime meridian at the appropriate time, the prime
meridian corresponding to zero degrees geographical longitude.
2.6 Whenever a specified time is used in international radiocommunication
activities, UTC shall be applied, unless otherwise indicated, and it shall be presented as
a four-digit group (0000-2359). The abbreviation UTC shall be used in all languages.
Section III – Designation of emissions
2.7 Emissions shall be designated according to their necessary bandwidth and
their classification in accordance with the method described in Appendix 1.
Band
number Symbols
Frequency range
(lower limit exclusive,
upper limit inclusive)
Corresponding
metric subdivision
Metric
abbreviations
for the bands
4 VLF 3 to 30 kHz Myriametric waves B.Mam
5 LF 30 to 300 kHz Kilometric waves B.km
6 MF 300 to 3 000 kHz Hectometric waves B.hm
7 HF 3 to 30 MHz Decametric waves B.dam
8 VHF 30 to 300 MHz Metric waves B.m
9 UHF 300 to 3 000 MHz Decimetric waves B.dm
10 SHF 3 to 30 GHz Centimetric waves B.cm
11 EHF 30 to 300 GHz Millimetric waves B.mm
12 300 to 3 000 GHz Decimillimetric waves
NOTE 1: “Band N” (N = band number) extends from 0.3 × 10N Hz to 3 × 10N Hz.
NOTE 2: Prefix: k = kilo (103), M = mega (106), G = giga (109).
46 Maritime Manual
ARTICLE 3
Technical characteristics of stations
3.1 The choice and performance of equipment to be used in a station and any
emissions therefrom shall satisfy the provisions of these Regulations.
3.2 Also, as far as is compatible with practical considerations, the choice of
transmitting, receiving and measuring equipment shall be based on the most recent
advances in the technique as indicated, inter alia, in ITU-R Recommendations.
3.3 Transmitting and receiving equipment intended to be used in a given part
of the frequency spectrum should be designed to take into account the technical
characteristics of transmitting and receiving equipment likely to be employed in
neighbouring and other parts of the spectrum, provided that all technically and
economically justifiable measures have been taken to reduce the level of unwanted
emissions from the latter transmitting equipment and to reduce the susceptibility to
interference of the latter receiving equipment.
3.4 To the maximum extent possible, equipment to be used in a station should
apply signal processing methods which enable the most efficient use of the frequency
spectrum in accordance with the relevant ITU-R Recommendations. These methods
include, inter alia, certain bandwidth expansion techniques, and in particular, in
amplitude-modulation systems, the use of the single-sideband technique.
3.5 Transmitting stations shall conform to the frequency tolerances specified
in Appendix 2.
3.6 Transmitting stations shall conform to the maximum permitted power
levels for spurious emissions or for unwanted emissions in the spurious domain
specified in Appendix 3. (WRC-03)
3.7 Transmitting stations shall conform to the maximum permitted power
levels for out-of-band emissions, or unwanted emissions in the out-of-band domain,
specified for certain services and classes of emission in the present Regulations. In the
absence of such specified maximum permitted power levels transmitting stations
should, to the maximum extent possible, satisfy the requirements relating to the
limitation of the out-of-band emissions, or unwanted emissions in the out-of-band
domain, specified in the most recent ITU-R Recommendations (see Resolution 27
(Rev.WRC-03)*). (WRC-03)
_______________
* Note by the Secretariat: This Resolution was revised by WRC-07.
Part B – SECTION I – RR3 47
3.8 Moreover, every effort should be made to keep frequency tolerances and
levels of unwanted emissions at the lowest values which the state of the technique and
the nature of the service permit.
3.9 The bandwidths of emissions also shall be such as to ensure the most
efficient utilization of the spectrum; in general this requires that bandwidths be kept at
the lowest values which the state of the technique and the nature of the service permit.
Appendix 1 is provided as a guide for the determination of the necessary bandwidth.
3.10 Where bandwidth-expansion techniques are used, the minimum spectral
power density consistent with efficient spectrum utilization shall be employed.
3.11 Wherever necessary for efficient spectrum use, the receivers used by any
service should comply as far as possible with the frequency tolerances of the
transmitters of that service, due regard being paid to the Doppler effect where
appropriate.
3.12 Receiving stations should use equipment with technical characteristics
appropriate for the class of emission concerned; in particular, selectivity should be
appropriate having regard to No. 3.9 on the bandwidths of emissions.
3.13 The performance characteristics of receivers should be adequate to ensure
that they do not suffer from interference due to transmitters situated at a reasonable
distance and which operate in accordance with these Regulations.
3.14 To ensure compliance with these Regulations, administrations shall
arrange for frequent checks to be made of the emissions of stations under their
jurisdiction. For this purpose, they shall use the means indicated in Article 16, if
required. The technique of measurements and the intervals of measurements to be
employed shall be, as far as is practicable, in accordance with the most recent ITU-R
Recommendations.
3.15 The use of damped wave emissions is forbidden in all stations.
48 Maritime Manual
ARTICLE 4
Assignment and use of frequencies
Section I – General rules
4.1 Member States shall endeavour to limit the number of frequencies and the
spectrum used to the minimum essential to provide in a satisfactory manner the
necessary services. To that end they shall endeavour to apply the latest technical
advances as soon as possible (CS 195).
4.2 Member States undertake that in assigning frequencies to stations which
are capable of causing harmful interference to the services rendered by the stations of
another country, such assignments are to be made in accordance with the Table of
Frequency Allocations and other provisions of these Regulations.
4.3 Any new assignment or any change of frequency or other basic
characteristic of an existing assignment (see Appendix 4) shall be made in such a way
as to avoid causing harmful interference to services rendered by stations using
frequencies assigned in accordance with the Table of Frequency Allocations in this
Chapter and the other provisions of these Regulations, the characteristics of which
assignments are recorded in the Master International Frequency Register.
4.4 Administrations of the Member States shall not assign to a station any
frequency in derogation of either the Table of Frequency Allocations in this Chapter or
the other provisions of these Regulations, except on the express condition that such a
station, when using such a frequency assignment, shall not cause harmful interference
to, and shall not claim protection from harmful interference caused by, a station
operating in accordance with the provisions of the Constitution, the Convention and
these Regulations.
4.5 The frequency assigned to a station of a given service shall be separated
from the limits of the band allocated to this service in such a way that, taking account of
the frequency band assigned to a station, no harmful interference is caused to services
to which frequency bands immediately adjoining are allocated.
4.6 For the purpose of resolving cases of harmful interference, the radio
astronomy service shall be treated as a radiocommunication service. However,
protection from services in other bands shall be afforded the radio astronomy service
only to the extent that such services are afforded protection from each other.
Part B – SECTION I – RR4 49
4.7 For the purpose of resolving cases of harmful interference, the space
research (passive) service and the earth exploration-satellite (passive) service shall be
afforded protection from different services in other bands only to the extent that these
different services are protected from each other.
4.8 Where, in adjacent Regions or sub-Regions, a band of frequencies is
allocated to different services of the same category (see Sections I and II of Article 5),
the basic principle is the equality of right to operate. Accordingly, the stations of each
service in one Region or sub-Region must operate so as not to cause harmful
interference to any service of the same or higher category in the other Regions or
sub-Regions. (WRC-03)
4.9 No provision of these Regulations prevents the use by a station in distress,
or by a station providing assistance to it, of any means of radiocommunication at its
disposal to attract attention, make known the condition and location of the station in
distress, and obtain or provide assistance.
4.10 Member States recognize that the safety aspects of radionavigation and
other safety services require special measures to ensure their freedom from harmful
interference; it is necessary therefore to take this factor into account in the assignment
and use of frequencies.
4.11 Member States recognize that among frequencies which have
long-distance propagation characteristics, those in the bands between 5 MHz and
30 MHz are particularly useful for long-distance communications; they agree to make
every possible effort to reserve these bands for such communications. Whenever
frequencies in these bands are used for short- or medium-distance communications, the
minimum power necessary shall be employed.
4.12 To reduce requirements for frequencies in the bands between 5 MHz and
30 MHz and thus to prevent harmful interference to long-distance
radiocommunications, administrations are encouraged to use, whenever practicable, any
other possible means of communication.
4.13 When special circumstances make it indispensable to do so, an
administration may, as an exception to the normal methods of working authorized by
these Regulations, have recourse to the special methods of working enumerated below,
on the sole condition that the characteristics of the stations still conform to those
inserted in the Master International Frequency Register:
4.14 a) a station in the fixed service or an earth station in the fixed-satellite
service may, under the conditions defined in Nos. 5.28 to 5.31, transmit to
mobile stations on its normal frequencies;
50 Maritime Manual
4.15 b) a land station may communicate, under the conditions defined in
Nos. 5.28 to 5.31, with fixed stations in the fixed service or earth stations in
the fixed-satellite service or other land stations of the same category.
4.15A Transmissions to or from high altitude platform stations shall be limited to
bands specifically identified in Article 5.
4.16 However, in circumstances involving the safety of life, or the safety of a
ship or aircraft, a land station may communicate with fixed stations or land stations of
another category.
4.17 Any administration may assign a frequency in a band allocated to the
fixed service or allocated to the fixed-satellite service to a station authorized to
transmit, unilaterally, from one specified fixed point to one or more specified fixed
points provided that such transmissions are not intended to be received directly by the
general public.
4.18 Any mobile station using an emission which satisfies the frequency
tolerance applicable to the coast station with which it is communicating may transmit
on the same frequency as the coast station on condition that the latter requests such
transmission and that no harmful interference is caused to other stations.
4.19 In certain cases provided for in Articles 31 and 51, aircraft stations are
authorized to use frequencies in the bands allocated to the maritime mobile service for
the purpose of communicating with stations of that service (see No. 51.73). (WRC-07)
4.20 Aircraft earth stations are authorized to use frequencies in the bands
allocated to the maritime mobile-satellite service for the purpose of communicating, via
the stations of that service, with the public telegraph and telephone networks.
4.21 In exceptional cases, land mobile earth stations in the land mobile-satellite
service may communicate with stations in the maritime mobile-satellite and
aeronautical mobile-satellite services. Such operations shall comply with the relevant
provisions of the Radio Regulations relating to those services and shall be subject to
agreement among administrations concerned, taking due account of No. 4.10.
4.22 Any emission capable of causing harmful interference to distress, alarm,
urgency or safety communications on the international distress and emergency
frequencies established for these purposes by these Regulations is prohibited.
Supplementary distress frequencies available on less than a worldwide basis should be
afforded adequate protection.
Part B – SECTION I – RR5 51
ARTICLE 5
Frequency allocations
Introduction
5.1 In all documents of the Union where the terms allocation, allotment and
assignment are to be used, they shall have the meaning given them in Nos. 1.16 to 1.18,
the terms used in the three working languages being as follows:
Frequency
distribution to French English Spanish
Services Attribution
(attribuer)
Allocation
(to allocate)
Atribución
(atribuir)
Areas or countries Allotissement
(allotir)
Allotment
(to allot)
Adjudicación
(adjudicar)
Stations Assignation
(assigner)
Assignment
(to assign)
Asignación
(asignar)
52 Maritime Manual
Section I – Regions and areas
5.2 For the allocation of frequencies the world has been divided into three
Regions1 as shown on the following map and described in Nos. 5.3 to 5.9:
5 - 0 1
7 5 °
6 0 °
4 0 °3 0 °2 0 °
0 °
2 0 °3 0 °4 0 °
6 0 °
7 5 °
6 0 °
4 0 °3 0 °2 0 °
0 °
2 0 °3 0 °4 0 °
6 0 °
170° 1 4 0 °1 6 0 ° 1 0 0 °1 2 0 ° 6 0 °8 0 ° 2 0 °4 0 ° 0 ° 2 0 ° 4 0 ° 6 0 ° 8 0 ° 1 0 0 ° 1 2 0 ° 1 4 0 ° 1 6 0 ° 1 8 0 °
170°
170°
1 4 0 °1 6 0 ° 1 0 0 °1 2 0 ° 6 0 °8 0 ° 2 0 °4 0 ° 0 ° 2 0 ° 4 0 ° 6 0 ° 8 0 ° 1 0 0 ° 1 2 0 ° 1 4 0 ° 1 6 0 ° 1 8 0 ° 170°
ABC
ABC
R E G I O N 1R E G I O N 2
R E G I O N 3 R E G I O N 3
The shaded part represents the Tropical Zones as defined in Nos. 5.16 to 5.20 and 5.21.
5.3 Region 1: Region 1 includes the area limited on the east by line A
(lines A, B and C are defined below) and on the west by line B, excluding any of the
territory of the Islamic Republic of Iran which lies between these limits. It also includes
the whole of the territory of Armenia, Azerbaijan, the Russian Federation, Georgia,
Kazakhstan, Mongolia, Uzbekistan, Kyrgyzstan, Tajikistan, Turkmenistan, Turkey and
Ukraine and the area to the north of Russian Federation which lies between lines A
and C.
5.4 Region 2: Region 2 includes the area limited on the east by line B and on
the west by line C.
5.5 Region 3: Region 3 includes the area limited on the east by line C and on
the west by line A, except any of the territory of Armenia, Azerbaijan, the Russian
Federation, Georgia, Kazakhstan, Mongolia, Uzbekistan, Kyrgyzstan, Tajikistan,
Turkmenistan, Turkey and Ukraine and the area to the north of Russian Federation. It
_______________
1 5.2.1 It should be noted that where the words “regions” or “regional” are without a capital
“R” in these Regulations, they do not relate to the three Regions here defined for purposes of
frequency allocation.
Part B – SECTION I – RR5 53
also includes that part of the territory of the Islamic Republic of Iran lying outside of
those limits.
5.6 The lines A, B and C are defined as follows:
5.7 Line A: Line A extends from the North Pole along meridian 40° East of
Greenwich to parallel 40° North; thence by great circle arc to the intersection of
meridian 60° East and the Tropic of Cancer; thence along the meridian 60° East to the
South Pole.
5.8 Line B: Line B extends from the North Pole along meridian 10° West of
Greenwich to its intersection with parallel 72° North; thence by great circle arc to the
intersection of meridian 50° West and parallel 40° North; thence by great circle arc to
the intersection of meridian 20° West and parallel 10° South; thence along meridian 20°
West to the South Pole.
5.9 Line C: Line C extends from the North Pole by great circle arc to the
intersection of parallel 65° 30′ North with the international boundary in Bering Strait;
thence by great circle arc to the intersection of meridian 165° East of Greenwich and
parallel 50° North; thence by great circle arc to the intersection of meridian 170° West
and parallel 10° North; thence along parallel 10° North to its intersection with meridian
120° West; thence along meridian 120° West to the South Pole.
5.10 For the purposes of these Regulations, the term “African Broadcasting
Area” means:
5.11 a) African countries, parts of countries, territories and groups of territories
situated between the parallels 40° South and 30° North;
5.12 b) islands in the Indian Ocean west of meridian 60° East of Greenwich,
situated between the parallel 40° South and the great circle arc joining the
points 45° East, 11° 30′ North and 60° East, 15° North;
5.13 c) islands in the Atlantic Ocean east of line B defined in No. 5.8 of these
Regulations, situated between the parallels 40° South and 30° North.
5.14 The “European Broadcasting Area” is bounded on the west by the western
boundary of Region 1, on the east by the meridian 40° East of Greenwich and on the
south by the parallel 30° North so as to include the northern part of Saudi Arabia and
that part of those countries bordering the Mediterranean within these limits. In addition,
Armenia, Azerbaijan, Georgia and those parts of the territories of Iraq, Jordan, Syrian
Arab Republic, Turkey and Ukraine lying outside the above limits are included in the
European Broadcasting Area. (WRC-07)
54 Maritime Manual
5.15 The “European Maritime Area” is bounded to the north by a line
extending along parallel 72° North from its intersection with meridian 55° East of
Greenwich to its intersection with meridian 5° West, then along meridian 5° West to its
intersection with parallel 67° North, thence along parallel 67° North to its intersection
with meridian 32° West; to the west by a line extending along meridian 32° West to its
intersection with parallel 30° North; to the south by a line extending along parallel 30°
North to its intersection with meridian 43° East; to the east by a line extending along
meridian 43° East to its intersection with parallel 60° North, thence along parallel 60°
North to its intersection with meridian 55° East and thence along meridian 55° East to
its intersection with parallel 72° North.
5.16 1) The “Tropical Zone” (see map in No. 5.2) is defined as:
5.17 a) the whole of that area in Region 2 between the Tropics of Cancer and
Capricorn;
5.18 b) the whole of that area in Regions 1 and 3 contained between the parallels
30° North and 35° South with the addition of:
5.19 i) The area contained between the meridians 40° East and 80° East of
Greenwich and the parallels 30° North and 40° North;
5.20 ii) that part of Libyan Arab Jamahiriya north of parallel 30° North.
5.21 2) In Region 2, the Tropical Zone may be extended to parallel 33°
North, subject to special agreements between the countries concerned in that Region
(see Article 6).
5.22 A sub-Region is an area consisting of two or more countries in the same
Region.
Part B – SECTION I – RR15 55
ARTICLE 15
Interferences
Section I – Interference from Radio Stations
15.1 § 1 All stations are forbidden to carry out unnecessary transmissions, or
the transmission of superfluous signals, or the transmission of false or misleading
signals, or the transmission of signals without identification (except as provided for in
Article 19).
15.2 § 2 Transmitting stations shall radiate only as much power as is necessary
to ensure a satisfactory service.
15.3 § 3 In order to avoid interference (see also Article 3 and No. 22.1):
15.4 a) locations of transmitting stations and, where the nature of the service
permits, locations of receiving stations shall be selected with particular care;
15.5 b) radiation in and reception from unnecessary directions shall be
minimized by taking the maximum practical advantage of the properties of
directional antennas whenever the nature of the service permits;
15.6 c) the choice and use of transmitters and receivers shall be in accordance
with the provisions of Article 3;
15.7 d) the conditions specified under No. 22.1 shall be fulfilled.
15.8 § 4 Special consideration shall be given to avoiding interference on
distress and safety frequencies, those related to distress and safety identified in
Article 31 and those related to safety and regularity of flight identified in
Appendix 27. (WRC-07)
15.9 § 5 The class of emission to be employed by a station should be such as
to achieve minimum interference and to assure efficient spectrum utilization. In general
this requires that in selecting the class of emission to meet these objectives every effort
shall be made to minimize the bandwidth occupied, taking into account the operational
and technical considerations of the service to be performed.
15.10 § 6 The out-of-band emissions of transmitting stations should not cause
harmful interference to services which operate in adjacent bands in accordance with
these Regulations and which use receivers in conformity with Nos. 3.3, 3.11, 3.12, 3.13
and relevant ITU-R Recommendations.
56 Maritime Manual
15.11 § 7 If, while complying with the provisions of Article 3, a station causes
harmful interference through its spurious emissions, special measures shall be taken to
eliminate such interference.
Section II – Interference from electrical apparatus and installations of any
kind except equipment used for industrial, scientific and medical applications
15.12 § 8 Administrations shall take all practicable and necessary steps to
ensure that the operation of electrical apparatus or installations of any kind, including
power and telecommunication distribution networks, but excluding equipment used for
industrial, scientific and medical applications, does not cause harmful interference to a
radiocommunication service and, in particular, to a radionavigation or any other safety
service operating in accordance with the provisions of these Regulations1.
Section III – Interference from equipment used for industrial, scientific
and medical applications
15.13 § 9 Administrations shall take all practicable and necessary steps to
ensure that radiation from equipment used for industrial, scientific and medical
applications is minimal and that, outside the bands designated for use by this
equipment, radiation from such equipment is at a level that does not cause harmful
interference to a radiocommunication service and, in particular, to a radionavigation or
any other safety service operating in accordance with the provisions of these
Regulations1.
Section IV – Tests
15.14 § 10 1) Before authorizing tests and experiments in any station, each
administration, in order to avoid harmful interference, shall prescribe the taking of all
possible precautions such as the choice of frequency and of time and the reduction or,
in all cases where this is possible, the suppression of radiation. Any harmful
interference resulting from tests and experiments shall be eliminated with the least
possible delay.
15.15 2) For the identification of transmissions made during tests,
adjustments or experiments, see Article 19.
_______________
1 15.12.1 and 15.13.1 In this matter, administrations should be guided by the latest relevant
ITU-R Recommendations.
Part B – SECTION I – RR15 57
15.16 3) In the aeronautical radionavigation service, it is undesirable, for
safety reasons, to transmit the normal identification during emissions conducted to
check or adjust equipment already in service. Unidentified emissions should however
be restricted to a minimum.
15.17 4) Signals for testing and adjustment shall be chosen in such a
manner that no confusion will arise with a signal, abbreviation, etc., having a special
meaning defined by these Regulations or by the International Code of Signals.
15.18 5) For testing stations in the mobile service see No. 57.9.
Section V – Reports of Infringements
15.19 § 11 Infringements of the Constitution, Convention or Radio Regulations
shall be reported to their respective administrations by the control organization, stations
or inspectors detecting them. For this purpose they shall use forms similar to the
specimen given in Appendix 9.
15.20 § 12 Representations relating to any serious infringement committed by a
station shall be made to the administration of the country having jurisdiction over the
station, by the administrations which detect it.
15.21 § 13 If an administration has information of an infringement of the
Convention or Radio Regulations, committed by a station over which it may exercise
authority, it shall ascertain the facts, fix the responsibility and take the necessary action.
Section VI – Procedure in a case of harmful interference
15.22 § 14 It is essential that Member States exercise the utmost goodwill and
mutual assistance in the application of the provisions of Article 45 of the Constitution
and of this Section to the settlement of problems of harmful interference.
15.23 § 15 In the settlement of these problems, due consideration shall be given
to all factors involved, including the relevant technical and operating factors, such as:
adjustment of frequencies, characteristics of transmitting and receiving antennas, time
sharing, change of channels within multichannel transmissions.
15.24 § 16 For the purpose of this Section, the term “administration” may
include the centralizing office designated by the administration, in accordance with
No. 16.3.
58 Maritime Manual
15.25 § 17 Administrations shall cooperate in the detection and elimination of
harmful interference, employing where appropriate the facilities described in Article 16
and the procedures detailed in this Section.
15.26 § 18 Where practicable, and subject to agreement by administrations
concerned, the case of harmful interference may be dealt with directly by their specially
designated monitoring stations or by direct coordination between their operating
organizations.
15.27 § 19 Full particulars relating to harmful interference shall, whenever
possible, be given in the form indicated in Appendix 10.
15.28 § 20 Recognizing that transmissions on distress and safety frequencies and
frequencies used for the safety and regularity of flight (see Article 31 and Appendix 27)
require absolute international protection and that the elimination of harmful interference
to such transmissions is imperative, administrations undertake to act immediately when
their attention is drawn to any such harmful interference. (WRC-07)
15.29 § 21 In cases of harmful interference where rapid action is required,
communications between administrations shall be transmitted by the quickest means
available and, subject to prior authorization by the administrations concerned in such
cases, information may be exchanged directly between specially designated stations of
the international monitoring system.
15.30 § 22 When a case of such harmful interference is reported by a receiving
station, it shall give to the transmitting station whose service is being interfered with all
possible information which will assist in determining the source and characteristics of
the interference.
15.31 § 23 If a case of harmful interference so justifies, the administration
having jurisdiction over the receiving station experiencing the interference shall inform
the administration having jurisdiction over the transmitting station whose service is
being interfered with, giving all possible information.
15.32 § 24 If further observations and measurements are necessary to determine
the source and characteristics of and to establish the responsibility for the harmful
interference, the administration having jurisdiction over the transmitting station whose
service is being interfered with may seek the cooperation of other administrations,
particularly of the administration having jurisdiction over the receiving station
experiencing the interference, or of other organizations.
Part B – SECTION I – RR15 59
15.33 § 25 When cases of harmful interference occur as a result of emissions
from space stations, the administrations having jurisdiction over these interfering
stations shall, upon request from the administration having jurisdiction over the station
experiencing the interference, furnish current ephemeral data necessary to allow
determination of the positions of the space stations when not otherwise known.
15.34 § 26 Having determined the source and characteristics of the harmful
interference, the administration having jurisdiction over the transmitting station whose
service is being interfered with shall inform the administration having jurisdiction over
the interfering station, giving all useful information in order that this administration
may take such steps as may be necessary to eliminate the interference.
15.35 § 27 On being informed that a station over which it has jurisdiction is
believed to have been the cause of harmful interference, an administration shall, as soon
as possible, acknowledge receipt of that information by the quickest means available.
Such acknowledgement shall not constitute an acceptance of responsibility. (WRC-2000)
15.36 § 28 When a safety service suffers harmful interference the administration
having jurisdiction over the receiving station experiencing the interference may also
approach directly the administration having jurisdiction over the interfering station. The
same procedure may also be followed in other cases with the prior approval of the
administration having jurisdiction over the transmitting station whose service is being
interfered with.
15.37 § 29 An administration receiving a communication to the effect that one of
its stations is causing harmful interference to a safety service shall promptly investigate
the matter and take any necessary remedial action and respond in a timely
manner. (WRC-2000)
15.38 § 30 When the service rendered by an earth station suffers harmful
interference, the administration having jurisdiction over the receiving station
experiencing such interference may also approach directly the administration having
jurisdiction over the interfering station.
15.39 § 31 If the harmful interference persists in spite of the action taken in
accordance with the procedures outlined above, the administration having jurisdiction
over the transmitting station whose service is being interfered with may address to the
administration having jurisdiction over the interfering station a report of irregularity or
infraction in accordance with the provisions of Section V.
15.40 § 32 If there is a specialized international organization for a particular
service, reports of irregularities and of infractions relating to harmful interference
caused or suffered by stations in this service may be addressed to such organization at
the same time as to the administration concerned.
60 Maritime Manual
15.41 § 33 1) If it is considered necessary, and particularly if the steps taken in
accordance with the procedures described above have not produced satisfactory results,
the administration concerned shall forward details of the case to the Bureau for its
information.
15.42 2) In such a case, the administration concerned may also request the
Bureau to act in accordance with the provisions of Section I of Article 13; but it shall
then supply the Bureau with the full facts of the case, including all the technical and
operational details and copies of the correspondence.
15.43 § 34 1) In the case where an administration has difficulty in identifying a
source of harmful interference in the HF bands and urgently wishes to seek the
assistance of the Bureau, it shall promptly inform the Bureau.
15.44 2) On receipt of this information, the Bureau shall immediately
request the cooperation of appropriate administrations or specially designated stations
of the international monitoring system that may be able to help in identifying the source
of harmful interference.
15.45 3) The Bureau shall consolidate all reports received in response to
requests under No. 15.44 and, using such other information as it has available, shall
promptly attempt to identify the source of harmful interference.
15.46 4) The Bureau shall thereafter forward its conclusions and
recommendations to the administration reporting the case of harmful interference.
These shall also be forwarded to the administration believed to be responsible for the
source of harmful interference, together with a request for prompt action.
Part B – SECTION I – RR17 61
ARTICLE 17
Secrecy
17.1 In the application of the appropriate provisions of the Constitution
and the Convention, administrations bind themselves to take the necessary measures to
prohibit and prevent:
17.2 a) the unauthorized interception of radiocommunications not intended
for the general use of the public;
17.3 b) the divulgence of the contents, simple disclosure of the existence,
publication or any use whatever, without authorization of information of any
nature whatever obtained by the interception of the radiocommunications
mentioned in No. 17.2.
62 Maritime Manual
ARTICLE 18
Licences
18.1 § 1 1) No transmitting station may be established or operated by a
private person or by any enterprise without a licence issued in an appropriate form and
in conformity with the provisions of these Regulations by or on behalf of the
government of the country to which the station in question is subject (however, see
Nos. 18.2, 18.8 and 18.11).
18.2 2) However, the government of a country may conclude with the
government of one or more neighbouring countries a special agreement concerning one
or several stations of its broadcasting service or of its land mobile services, operating on
frequencies above 41 MHz, situated in the territory of a neighbouring country and
intended to improve national coverage. This agreement, which shall be compatible with
the provisions of the present Regulations as well as of those regional agreements to
which the countries concerned are signatories, may allow exceptions to the provisions
of No. 18.1 and shall be communicated to the Secretary-General in order that it may be
brought to the notice of administrations for their information.
18.3 3) Mobile stations which are registered in a territory or group of
territories which does not have full responsibility for its international relations may be
considered, in so far as the issue of licences is concerned, as subject to the authority of
that territory or group of territories.
18.4 § 2 The holder of a licence is required to preserve the secrecy of
telecommunications, as provided in the relevant provisions of the Constitution and the
Convention. Moreover, the licence shall mention, specifically or by reference, that if
the station includes a receiver, the interception of radiocommunication correspondence,
other than that which the station is authorized to receive, is forbidden, and that in cases
where such correspondence is involuntarily received, it shall not be reproduced, nor
communicated to third parties, nor used for any purpose, and even its existence shall
not be disclosed.
18.5 § 3 To facilitate the verification of licences issued to mobile stations
and mobile earth stations, a translation of the text in one of the working languages of
the Union shall be added, when necessary, to the text written in the national language.
18.6 § 4 1) The government which issues a licence to a mobile station or a
mobile earth station shall indicate therein in clear form the particulars of the station,
including its name, call sign and, where appropriate, the public correspondence
category, as well as the general characteristics of the installation.
Part B – SECTION I – RR18 63
18.7 2) For land mobile stations, including stations consisting only of
one or more receivers, a clause shall be included in the licence, specifically or by
reference, under which the operation of these stations shall be forbidden in countries
other than the country in which the licence is issued, except as may be provided by
special agreement between the governments of the countries concerned.
18.8 § 5 1) In the case of a new registration of a ship or aircraft in
circumstances where delay is likely to occur in the issue of a licence by the country in
which it is to be registered, the administration of the country from which the mobile
station or mobile earth station wishes to make its voyage or flight may, at the request of
the operating company, issue a certificate to the effect that the station complies with
these Regulations. This certificate, drawn up in a form determined by the issuing
administration, shall give the particulars mentioned in No. 18.6 and shall be valid only
for the duration of the voyage or flight to the country in which the registration of the
ship or aircraft will be effected, or for a period of three months, whichever is less.
18.9 2) The administration issuing the certificate shall inform the
administration responsible for issuing the licence of the action taken.
18.10 3) The holder of the certificate shall comply with the provisions of
these Regulations applicable to licence holders.
18.11 § 6 In the case of hire, lease or interchange of aircraft, the
administration having authority over the aircraft operator receiving an aircraft under
such an arrangement may, by agreement with the administration of the country in which
the aircraft is registered, issue a licence in conformity with that specified in No. 18.6 as
a temporary substitute for the original licence.
64 Maritime Manual
ARTICLE 19
Identification of stations
Section I – General provisions
19.1 § 1 All transmissions shall be capable of being identified either by
identification signals or by other means1.
19.2 § 2 1) All transmissions with false or misleading identification are
prohibited.
19.3 2) Where practicable and in appropriate services, identification
signals should be automatically transmitted in accordance with relevant ITU-R
Recommendations.
19.4 3) All transmissions in the following services should, except as
provided in Nos. 19.13 to 19.15, carry identification signals:
19.5 a) amateur service;
19.6 b) broadcasting service;
19.7 c) fixed service in the bands below 28 000 kHz;
19.8 d) mobile service;
19.9 e) standard frequency and time signal service.
19.10 4) All operational transmissions by radiobeacons shall carry
identification signals. However, it is recognized that, for radiobeacons and for certain
other radionavigation services that normally carry identification signals, during periods
of malfunction or other non-operational service the deliberate removal of identification
signals is an agreed means of warning users that the transmissions cannot safely be used
for navigational purposes.
_______________
1 19.1.1 In the present state of the technique, it is recognized nevertheless that the
transmission of identifying signals for certain radio systems (e.g. radiodetermination, radio relay
systems and space systems) is not always possible.
Part B – SECTION I – RR19 65
19.11 5) All transmissions by satellite emergency position-indicating
radiobeacons (EPIRBs) operating in the band 406-406.1 MHz or the band 1 645.5-
1 646.5 MHz, or by EPIRBs using digital selective calling techniques, shall carry
identification signals.
19.12 6) When identification signals are transmitted they shall comply
with the provisions of this Article.
19.13 7) However, the requirements for certain transmissions to carry
identification signals need not apply to:
19.14 a) survival craft stations when transmitting distress signals
automatically;
19.15 b) emergency position-indicating radiobeacons (except for those in
No. 19.11).
19.16 § 3 In transmissions carrying identification signals a station shall be
identified by a call sign, by a maritime mobile service identity or by other recognized
means of identification which may be one or more of the following: name of station,
location of station, operating agency, official registration mark, flight identification
number, selective call number or signal, selective call identification number or signal,
characteristic signal, characteristic of emission or other clearly distinguishing features
readily recognized internationally.
19.17 § 4 For transmissions carrying identification signals, in order that stations
may be readily identified, each station shall transmit its identification as frequently as
practicable during the course of transmissions, including those made for tests,
adjustments or experiments. During such transmissions, however, identification signals
shall be transmitted at least hourly, preferably within the period from five minutes
before to five minutes after the hour (UTC) unless to do so would cause unreasonable
interruption of traffic, in which case identification shall be given at the beginning and
end of transmissions.
19.18 § 5 Identification signals shall wherever practicable be in one of the
following forms:
19.19 a) speech, using simple amplitude or frequency modulation;
19.20 b) international Morse code transmitted at manual speed;
19.21 c) a telegraph code compatible with conventional printing equipment;
19.22 d) any other form recommended by the Radiocommunication Sector.
19.23 § 6 To the extent possible the identification signal should be transmitted
in accordance with relevant ITU-R Recommendations.
66 Maritime Manual
19.24 § 7 Administrations should ensure that wherever practicable
superimposed identification methods be employed in accordance with ITU-R
Recommendations.
19.25 § 8 When a number of stations work simultaneously in a common circuit,
either as relay stations, or in parallel on different frequencies, each station shall, as far
as practicable, transmit its own identification or those of all the stations concerned.
19.26 § 9 Administrations shall ensure, except in the cases mentioned in
Nos. 19.13 to 19.15, that all transmissions not carrying identification signals can be
identified by other means when they are capable of causing harmful interference to the
services of another administration operating in accordance with these Regulations.
19.27 § 10 Administrations shall, having regard to the provisions of these
Regulations relating to the notification of assignments for recording in the Master
Register, adopt their own measures to ensure compliance with the provisions of
No. 19.26.
19.28 § 11 Each Member State reserves the right to establish its own measures
for identifying its stations used for national defence. However, it shall use, as far as
possible, call signs recognizable as such, and containing the distinctive characters of its
nationality.
Section II – Allocation of international series and assignment of call signs
19.28A § 11A 1) For the purpose of the supply of identification signals, a territory
or geographical area shall be understood to mean the territory within the limits of
which the station is located. For mobile stations, it shall be understood to mean the
territory within the limits of which the responsible administration is located. A territory
which does not have full responsibility for its international relations shall also be
considered as a geographical area for this purpose.
19.28B 2) In all documents of the Union where the terms allocation of call
sign series and assignment of call signs are to be used, they shall be used with the
following meaning:
Identification means Terms used in these Regulations
International series of call signs (including
maritime identification digits (MIDs) and
selective call numbers)
Allocation to the administration of a Member
State (see definition in No. 1002 of the
Constitution)
Call signs (including maritime
identification digits (MIDs) and selective
call numbers)
Assignment by any administration to stations
operating in a territory or geographical area
(see No. 19.28A)
Part B – SECTION I – RR19 67
19.29 § 12 1) All stations open to international public correspondence, all
amateur stations, and other stations which are capable of causing harmful interference
beyond the boundaries of the territory or geographical area in which they are located,
shall have call signs from the international series allocated to its administration as given
in the Table of Allocation of International Call Sign Series in Appendix 42.
19.30 2) As the need arises, ship stations and ship earth stations to which
the provisions of Chapter IX apply, and coast stations, coast earth stations, or other
non-shipborne stations capable of communicating with such ship stations, shall have
assigned to them maritime mobile service identities in accordance with Section VI of
this Article. (WRC-07)
19.31 3) It is not compulsory to assign call signs from the international
series to stations identified by maritime mobile service identities or which are easily
identified by other means (see No. 19.16) and whose signals of identification or
characteristics of emission are published in international documents.
19.31A 4) Means shall be provided for uniquely identifying mobile stations
operating in automated terrestrial or satellite communication systems for the purposes
of answering distress calls, for avoiding interference and for billing. Identification of
the mobile station by accessing a registration database is satisfactory, provided that the
system can associate the mobile station calling number with the particular mobile
station user. (WRC-03)
19.32 § 13 Should the available call sign series in Appendix 42 be exhausted,
new call sign series may be allocated according to the principles set out in Resolu-
tion 13 (Rev.WRC-97) relating to the formation of call signs and the allocation of new
international series.
19.33 § 14 Between radiocommunication conferences, the Secretary-General is
authorized to deal with questions relating to changes in the allocation of series of call
signs, on a provisional basis, and subject to confirmation by the following conference
(see also No. 19.32).
19.34 § 15 The Secretary-General shall be responsible for allocating maritime
identification digits (MIDs) to administrations and shall regularly publish information
regarding allocated MIDs.
68 Maritime Manual
19.35 § 16 The Secretary-General shall be responsible for allocating additional
maritime identification digits (MIDs) to administrations within the limits specified,
provided that it is ascertained that the possibilities offered by the MIDs allocated to an
administration will soon be exhausted despite judicious ship station identity assignment
as outlined in Section VI. (WRC-03)
19.36 § 17 Each administration has been allocated one or more maritime
identification digit (MID) for its use. A second or subsequent MID should not be
requested2 unless the previously allocated MID is more than 80% exhausted in the basic
category of three trailing zeros and the rate of assignments is such that 90% exhaustion
is foreseen. (WRC-03)
19.37 § 18 The Secretary-General shall be responsible for supplying series of
selective call numbers or signals (see Nos. 19.92 to 19.95) at the request of the
administrations concerned.
19.38 § 19 1) Each administration shall choose the call signs from the
international series allocated or supplied to it; and shall notify this information to the
Secretary-General together with the information which is to appear in Lists I, IV and V.
These notifications do not include call signs assigned to amateur and experimental
stations. (WRC-07)
19.39 2) Each administration shall choose the maritime mobile service
identities of its stations from the maritime identification digits allocated to it and notify
this information to the Secretary-General for inclusion in the relevant lists, as provided
for in Article 20.
19.40 3) The Secretary-General shall ensure that the same call sign, the
same maritime mobile service identity, the same selective call number or the same
identification number is not assigned more than once and that call signs which might be
confused with distress signals, or with other signals of the same nature, are not
assigned.
_______________
2 19.36.1 In no circumstances may an administration claim more MIDs than the total
number of its ship stations notified to ITU divided by 1 000, plus one. Administrations shall
make every attempt to reuse the Maritime Mobile Service Identities (MMSI) assigned from
earlier MID resources, which become redundant after ships leave their national ship registry.
Such numbers should be considered for reassignment after being absent from at least two
successive editions of List V of the ITU service publications. Administrations seeking additional
MID resources must meet the criteria of having notified all previous assignments, in accordance
with No. 20.16. This criteria applies only to MMSIs in the basic category and to all MIDs
assigned to the administration. (WRC-07)
Part B – SECTION I – RR19 69
19.41 § 20 1) When a fixed station uses more than one frequency in the
international service, each frequency may be identified by a separate call sign used
solely for this frequency.
19.42 2) When a broadcasting station uses more than one frequency in the
international service, each frequency may be identified by a separate call sign used
solely for this frequency or by some other appropriate means, such as announcing the
name of the place and frequency used.
19.43 3) When a land station uses more than one frequency, each
frequency may, if desired, be identified by a separate call sign.
19.44 4) Where practicable, coast stations should use a common call sign
for each frequency series3.
Section III – Formation of call signs
19.45 § 21 1) The twenty-six letters of the alphabet, as well as digits in the
cases specified below, may be used to form call signs. Accented letters are excluded.
19.46 2) However, the following combinations shall not be used as call
signs:
19.47 a) combinations which might be confused with distress signals or with
other signals of a similar nature;
19.48 b) combinations in Recommendation ITU-R M.1172 that are reserved
for the abbreviations to be used in the radiocommunication services. (WRC-03)
19.50 § 22 Call signs in the international series are formed as indicated in
Nos. 19.51 to 19.71. The first two characters shall be two letters or a letter followed by
a digit or a digit followed by a letter. The first two characters or in certain cases the first
character of a call sign constitute the nationality identification4.
_______________
3 19.44.1 By “frequency series” is meant a group of frequencies each of which belongs to
one of the different bands between 4 000 kHz and 27 500 kHz that are allocated exclusively to
the maritime mobile service.
4 19.50.1 For call sign series beginning with B, F, G, I, K, M, N, R, W and 2, only the first
character is required for nationality identification. In the cases of half series (i.e. when the first
two characters are allocated to more than one Member State), the first three characters are
required for nationality identification. (WRC-03)
70 Maritime Manual
19.51 Land and fixed stations
19.52 § 23 1)
– two characters and one letter, or
– two characters and one letter followed by not more than three digits
(other than the digits 0 and 1 in cases where they immediately follow
a letter).
19.53 2) However, it is recommended that, as far as possible, the call
signs of fixed stations consist of:
– two characters and one letter followed by two digits (other than the
digits 0 and 1 in cases where they immediately follow a letter).
19.54 Ship stations
19.55 § 24
– two characters and two letters, or
– two characters, two letters and one digit (other than the digits 0 or 1),
or
– two characters (provided that the second is a letter) followed by four
digits (other than the digits 0 or 1 in cases where they immediately
follow a letter), or
– two characters and one letter followed by four digits (other than the
digits 0 or 1 in cases where they immediately follow a
letter). (WRC-07)
19.57 Aircraft stations
19.58 § 25
– two characters and three letters.
19.59 Ship’s survival craft stations
19.60 § 26
– the call sign of the parent ship followed by two digits (other than the
digits 0 or 1 in cases where they immediately follow a letter).
19.61 Emergency position-indicating radiobeacon stations
19.62 § 27
– the Morse letter B and/or the call sign of the parent ship to which the
radiobeacon belongs.
Part B – SECTION I – RR19 71
19.63 Aircraft survival craft stations
19.64 § 28
– the complete call sign of the parent aircraft (see No. 19.58), followed
by a single digit other than 0 or 1.
19.65 Land mobile stations
19.66 § 29
– two characters (provided that the second is a letter) followed by four
digits (other than the digits 0 or 1 in cases where they immediately
follow a letter), or
– two characters and one or two letters followed by four digits (other
than the digits 0 or 1 in cases where they immediately follow a letter).
19.67 Amateur and experimental stations
19.68 § 30 1)
– one character (provided that it is the letter B, F, G, I, K, M, N, R or
W) and a single digit (other than 0 or 1), followed by a group of not
more than four characters, the last of which shall be a letter, or
– two characters and a single digit (other than 0 or 1), followed by a
group of not more than four characters, the last of which shall be a
letter.5 (WRC-03)
19.68A 1A) On special occasions, for temporary use, administrations
may authorize use of call signs with more than the four characters referred to in
No. 19.68. (WRC-03)
19.69 2) However, the prohibition of the use of the digits 0 and 1 does not
apply to amateur stations.
19.70 Stations in the space service
19.71 § 31 When call signs for stations in the space service are employed, it is
recommended that they consist of:
– two characters followed by two or three digits (other than the digits 0
and 1 in cases where they immediately follow a letter).
_______________
5 19.68.1 In the case of half series (i.e. when the first two characters are allocated to more
than one Member State), the first three characters are required for nationality identification. In
such cases, the call sign shall consist of three characters followed by a single digit and a group
of not more than three characters, the last of which shall be a letter. (WRC-07)
72 Maritime Manual
Section IV – Identification of stations using radiotelephony
19.72 § 32 Stations using radiotelephony shall be identified as indicated in
Nos. 19.73 to 19.82A. (WRC-03)
19.73 § 33 1) Coast stations
– a call sign (see No. 19.52); or
– the geographical name of the place as it appears in the List of Coast
Stations and Special Service Stations, followed preferably by the
word RADIO or by any other appropriate indication. (WRC-07)
19.74 2) Ship stations
– a call sign (see Nos. 19.55 and 19.56); or
– the official name of the ship preceded, if necessary, by the name of
the owner on condition that there is no possible confusion with
distress, urgency and safety signals; or
– its selective call number or signal.
19.75 3) Ship’s survival craft stations
– a call sign (see No. 19.60); or
– a signal of identification consisting of the name of the parent ship
followed by two digits.
19.76 4) Emergency position-indicating radiobeacon stations
When speech transmission is used:
– the name and/or the call sign of the parent ship to which the
radiobeacon belongs. (WRC-07)
19.77 § 34 1) Aeronautical stations
– the name of the airport or geographical name of the place followed, if
necessary, by a suitable word indicating the function of the station.
19.78 2) Aircraft stations
– a call sign (see No. 19.58), which may be preceded by a word
designating the owner or the type of aircraft; or
– a combination of characters corresponding to the official registration
mark assigned to the aircraft; or
– a word designating the airline, followed by the flight identification
number.
Part B – SECTION I – RR19 73
19.79 3) In the exclusive aeronautical mobile frequency bands, aircraft
stations using radiotelephony may use other methods of identification, after special
agreement between governments, and on condition that they are internationally known.
19.80 4) Aircraft survival craft stations
– a call sign (see No. 19.64).
19.81 § 35 1) Base stations
– a call sign (see No. 19.52); or
– the geographical name of the place followed, if necessary, by any
other appropriate indication.
19.82 2) Land mobile stations
– a call sign (see No. 19.66); or
– the identity of the vehicle or any other appropriate indication.
19.82A § 35A Amateur stations and experimental stations
– a call sign (see No. 19.68). (WRC-03)
Section V – Selective call numbers in the maritime mobile service
19.83 § 36 When stations of the maritime mobile service use selective calling
devices in accordance with Recommendations ITU-R M.476-5 and ITU-R M.625-3,
their call numbers shall be assigned by the responsible administrations in accordance
with the provisions below. (WRC-07)
19.84 Formation of ship station selective call numbers and coast station identi-
fication numbers
19.85 § 37 1) The ten digits from 0 to 9 inclusive shall be used to form
selective call numbers.
19.86 2) However, combinations of numbers commencing with the digits
00 (zero, zero) shall not be used when forming the identification numbers for coast
stations.
19.87 3) Ship station selective call numbers and coast station
identification numbers in the series are formed as indicated in Nos. 19.88, 19.89 and
19.90.
19.88 4) Coast station identification numbers
– four digits (see No. 19.86).
74 Maritime Manual
19.89 5) Ship station selective call numbers
– five digits.
19.90 6) Predetermined groups of ship stations
– five digits consisting of:
– the same digit repeated five times; or
– two different digits repeated alternately.
19.91 Assignment of ship station selective call numbers and coast station
identification numbers
19.92 § 38 1) In cases where selective call numbers for ship stations and
identification numbers for coast stations are required for use in the maritime mobile
service, the selective call numbers and identification numbers shall be supplied by the
Secretary-General on request. Upon notification by an administration of the
introduction of selective calling for use in the maritime mobile service: (WRC-07)
19.93 a) selective call numbers for ships will be supplied as required in blocks
of 100 (one hundred);
19.94 b) coast station identification numbers will be supplied in blocks of 10
(ten) to meet actual requirements;
19.95 c) selective call numbers for selective calling of predetermined groups
of ship stations in accordance with No. 19.90 will be supplied as required as
single numbers.
19.96 2) Each administration shall choose the selective call numbers to be
assigned to its ship stations from the blocks of the series supplied to it. Administrations
shall notify the Bureau immediately in accordance with No. 20.16 when assigning
selective call numbers to ship stations.
19.96A 3) Five-digit ship station selective call numbers shall be assigned
for narrow-band direct printing (NBDP) equipment (as described in Recommendation
ITU-R M.476-5). (WRC-07)
19.97 4) Each administration shall choose the coast station identification
numbers to be assigned to its coast stations from the blocks of the series supplied to it.
Part B – SECTION I – RR19 75
Section VI – Maritime mobile service identities (WRC-07)
19.98 A – General
19.99 § 39 When a station6 operating in the maritime mobile service or the
maritime mobile-satellite service is required to use maritime mobile service identities,
the responsible administration shall assign the identity to the station in accordance with
the provisions described in Annexes 1 to 5 of Recommendation ITU-R M.585-4. In
accordance with No. 20.16, administrations shall notify the Radiocommunication
Bureau immediately when assigning maritime mobile service identities. (WRC-07)
19.100 § 40 1) Maritime mobile service identities are formed of a series of nine
digits which are transmitted over the radio path in order to uniquely identify ship
stations, ship earth stations, coast stations, coast earth stations, and other non-shipborne
stations operating in the maritime mobile service or the maritime mobile-satellite
service, and group calls. (WRC-07)
19.101 2) These identities are formed in such a way that the identity or part
thereof can be used by telephone and telex subscribers connected to the public
telecommunications network principally to call ships automatically in the shore-to-ship
direction. Access to public networks may also be achieved by means of free-form
numbering plans, so long as the ship can be uniquely identified using the system’s
registration database (see No. 19.31A) to obtain the ship station identity, call sign or
ship name and nationality. (WRC-03)
19.102 3) The types of maritime mobile service identities shall be as
described in Annexes 1 to 5 of Recommendation ITU-R M.585-4. (WRC-07)
19.108 B – Maritime identification digits (MIDs)
19.108A § 41 The maritime identification digits M1I2D3 are an integral part of the
maritime mobile service identity and denote the geographical area of the administration
responsible for the station so identified. (WRC-07)
19.110 C – Maritime mobile service identities (WRC-07)
19.111 § 43 1) Administrations shall follow Annexes 1 to 5 of Recommendation
ITU-R M.585-4 concerning the assignment and use of maritime mobile service
identities. (WRC-07)
_______________
6 19.99.1 In this Section a reference to a ship station or a coast station may include the
respective earth stations.
76 Maritime Manual
19.112 2) Administrations should: (WRC-07)
19.113 a) make optimum use of the possibilities of forming identities from the
single MID allocated to them; (WRC-07)
19.114 b) take particular care in assigning ship station identities with six
significant digits (i.e. having three-trailing-zero identities), which should be
assigned only to ship stations which can reasonably be expected to require
such an identity for automatic access on a worldwide basis to public switched
networks, in particular for mobile-satellite systems accepted for use in the
GMDSS on or before 1 February 2002, as long as those systems maintain the
MMSI as part of their numbering scheme. (WRC-07)
Section VII – Special provisions
19.127 § 47 1) In the aeronautical mobile service, after communication has been
established by means of the complete call sign, the aircraft station may use, if confusion
is unlikely to arise, an abbreviated call sign or identification consisting of:
19.128 a) in radiotelegraphy, the first character and last two letters of the
complete call sign (see No. 19.58);
19.129 b) in radiotelephony:
– the first character of the complete call sign; or
– the abbreviation of the name of the owner of the aircraft
(company or individual); or
– the type of aircraft;
followed by the last two letters of the complete call sign (see No. 19.58) or by
the last two characters of the registration mark.
19.130 2) The provisions of Nos. 19.127, 19.128 and 19.129 may be
amplified or modified by agreement between administrations concerned.
19.131 § 48 The distinguishing signals allotted to ships for visual and aural
signalling shall, in general, agree with the call signs of ship stations.
Part B – SECTION I – RR20 77
ARTICLE 20
Service publications and online information systems (WRC-07)
Section I – Titles and contents of service publications (WRC-07)
20.1 § 1 The following publications shall be issued by the Secretary-General.
As circumstances warrant and in response to individual requests by administrations, the
published information shall also be available in various formats and by appropriate
means. (WRC-07)
20.2 § 2 List I – The International Frequency List.
20.3 This List shall contain:
20.4 a) particulars of frequency assignments recorded in the Master
International Frequency Register;
20.5 b) the frequencies prescribed by these Regulations for common use by
certain services; (WRC-07)
20.6 c) the allotments in the Allotment Plans included in Appendices 25, 26
and 27.
20.7 § 3 List IV – List of Coast Stations and Special Service Stations. (WRC-07)
20.8 § 4 List V – List of Ship Stations and Maritime Mobile Service Identity
Assignments. (WRC-07)
20.12 § 8 List VIII – List of International Monitoring Stations.
20.13 § 9 List VIII A – List of Stations in the Space Radiocommunication
Services and in the Radio Astronomy Service.
20.14 § 10 Manual for Use by the Maritime Mobile and Maritime Mobile-
Satellite Services.
Section II – Online information systems (WRC-07)
20.14A § 10A The following online information system(s) are made available by the
Radiocommunication Bureau:
the ITU Maritime mobile Access and Retrieval System (MARS). (WRC-07)
78 Maritime Manual
Section III – Preparation and amendment of service publications
and online information systems (WRC-07)
20.15 § 11 The form, the content and the periodicity of each publication shall be
decided by the Radiocommunication Bureau in consultation with administrations and
the international organizations concerned. Similar consultation shall be made with
regard to the maritime online information systems. (WRC-07)
20.16 § 12 1) Administrations shall take all appropriate measures to notify the
Radiocommunication Bureau immediately of any changes in the operational
information contained in Lists IV and V, in view of the importance of this information,
particularly with regard to safety. In the case of the data published in List V, which is
also made available online through MARS, administrations shall communicate those
changes at least once a month. In the case of other publications, administrations shall
communicate the changes in the information contained in them as soon as
possible. (WRC-07)
20.16A 2) The names of the administrations which have failed to notify the
Radiocommunication Bureau of the changes in the operational information contained in
Lists IV and V shall be published in these Lists.
20.16B 3) The Radiocommunication Bureau will periodically request
administrations to reconfirm the information published in Lists IV and V. If no
information has been received by the Radiocommunication Bureau for two consecutive
editions of Lists IV and V, unvalidated information shall be deleted. The
Radiocommunication Bureau shall however inform the administration concerned before
taking such action. (WRC-07)
20.17 § 13 For the purpose of the service publications, a “country” shall be
understood to mean the territory within the limits of which the station is located; a
territory which does not have full responsibility for its international relations shall also
be considered as a country for this purpose. (WRC-03)
Part B – SECTION I – RR28 79
ARTICLE 28
Radiodetermination services
Section I – General provisions
28.1 § 1 Administrations which have established a radiodetermination service
shall take the necessary steps to ensure the effectiveness and regularity of that service;
however they accept no responsibility for the consequences that might arise from the
use of inaccurate information furnished, defective working, or failure of their stations.
28.2 § 2 In the case of doubtful or unreliable observations, the station taking
the bearing or fixing the position shall, whenever possible, notify the station to which
this information is given of any such doubt or unreliability.
28.3 § 3 Administrations shall notify to the Bureau the characteristics of each
radiodetermination station providing an international service of value to the maritime
mobile service and, if considered necessary, for each station or group of stations, the
sectors in which the information furnished is normally reliable. This information is
published in the List of Coast Stations and Special Service Stations (List IV), and the
Bureau shall be notified of any change of a permanent nature. (WRC-07)
28.4 § 4 The method of identification of radiodetermination stations shall be
so chosen as to avoid any doubt as to their identity.
28.5 § 5 Signals sent by radiodetermination stations shall be such as to permit
accurate and precise measurements.
28.6 § 6 Any information concerning modification or irregularity of working
of a radiodetermination station shall be notified without delay in the following manner:
28.7 a) land stations of countries operating a radiodetermination service shall
send out daily, if necessary, notices of modifications or irregularities in
working until such time as normal working is restored or, if a permanent
alteration has been made, until such time as it can reasonably be taken that all
navigators interested have been warned;
28.8 b) permanent alterations or irregularities of long duration shall be
published as soon as possible in the relevant notices to navigators.
80 Maritime Manual
Section II – Provisions for the radiodetermination-satellite service
28.9 § 7 1) The provisions of Nos. 28.1 to 28.8, excluding No. 28.2, shall be
applied to the maritime radionavigation-satellite service.
28.10 2) The provisions of Nos. 28.1 to 28.8, excluding Nos. 28.2 and
28.3, shall be applied to the aeronautical radionavigation-satellite service.
28.11 3) The provisions of Nos. 28.1 to 28.8, excluding Nos. 28.2 and
28.3, shall be applied to the radiodetermination-satellite service.
Section III – Radio direction-finding stations
28.12 § 8 1) In the maritime radionavigation service, the radiotelegraph
frequency normally used for radio direction-finding is 410 kHz. All direction-finding
stations of the maritime radionavigation service using radiotelegraphy shall be able to
use this frequency. They shall, in addition, be able to take bearings on 500 kHz,
especially for locating stations sending signals of distress, alarm and urgency.
28.13 2) Where a radio direction-finding service is provided in the
authorized bands between 1 606.5 kHz and 2 850 kHz, the radio direction-finding
stations should be able to take bearings on the radiotelephone distress and calling
frequency 2 182 kHz. (WRC-03)
28.14 3) Where a radio direction-finding station as defined in No. 1.12,
operates in the bands between 156 MHz and 174 MHz, it should be able to take
bearings on the VHF distress and calling frequency 156.8 MHz and on the VHF digital
selective calling frequency 156.525 MHz.
28.16 § 9 In the absence of prior arrangements, an aircraft station which calls a
radio direction-finding station for a bearing shall use for this purpose a frequency on
which the station called normally keeps watch.
28.17 § 10 In the aeronautical radionavigation service, the procedure
contemplated for radio direction-finding in this Section is applicable, except where
special procedures are in force as a result of arrangements concluded between the
administrations concerned.
Part B – SECTION I – RR28 81
Section IV – Radiobeacon stations
28.18 § 11 When an administration thinks it desirable in the interests of
navigation to organize a service of radiobeacon stations, it may use for this purpose:
28.19 a) radiobeacons properly so-called, established on land or on ships
permanently moored or, exceptionally, on ships navigating in a restricted area,
the limits of which are known and published. The emissions of these
radiobeacons may have either directional or non-directional patterns;
28.20 b) fixed stations, coast stations or aeronautical stations designated to
function as radiobeacons, at the request of mobile stations.
28.21 § 12 1) Radiobeacons properly so-called shall use the frequency bands
which are available to them under Chapter II.
28.22 2) Other stations notified as radiobeacons shall use for this purpose
their normal working frequency and their normal class of emission.
28.23 3) The power radiated by each radiobeacon properly so-called shall
be adjusted to the value necessary to produce the stipulated field strength at the limit of
the range required (see Appendix 12).
28.24 § 13 Special rules applicable to aeronautical radio beacons operating in the
bands between 160 kHz and 535 kHz and to the maritime radio beacons operating in the
bands between 283.5 kHz and 335 kHz are given in Appendix 12.
82 Maritime Manual
ARTICLE 30
General provisions
Section I – Introduction
30.1 § 1 This Chapter contains the provisions for the operational use of the
global maritime distress and safety system (GMDSS), whose functional requirements,
system elements and equipment carriage requirements are set forth in the International
Convention for the Safety of Life at Sea (SOLAS), 1974, as amended. This Chapter
also contains provisions for initiating distress, urgency and safety communications by
means of radiotelephony on the frequency 156.8 MHz (VHF channel 16). (WRC-07)
30.2 § 2 No provision of these Regulations prevents the use by a mobile
station or a mobile earth station in distress of any means at its disposal to attract
attention, make known its position, and obtain help (see also No. 4.9).
30.3 § 3 No provision of these Regulations prevents the use by stations on
board aircraft, ships engaged in search and rescue operations, land stations, or coast
earth stations, in exceptional circumstances, of any means at their disposal to assist a
mobile station or a mobile earth station in distress (see also Nos. 4.9 and 4.16).
Section II – Maritime provisions
30.4 § 4 The provisions specified in this Chapter are obligatory in the
maritime mobile service and the maritime mobile-satellite service for all stations using
the frequencies and techniques prescribed for the functions set out herein (see also
No. 30.5). (WRC-07)
30.5 § 5 The International Convention for the Safety of Life at Sea (SOLAS),
1974 as amended, prescribes which ships and which of their survival craft shall be
provided with radio equipment, and which ships shall carry portable radio equipment
for use in survival craft. It also prescribes the requirements which shall be met by such
equipment.
Part B – SECTION I – RR30 83
30.6 § 6 Ship earth stations located at rescue coordination centres1 may be
authorized by an administration to communicate for distress and safety purposes with
any other station using bands allocated to the maritime mobile-satellite service, when
special circumstances make it essential, notwithstanding the methods of working
provided for in these Regulations.
30.7 § 7 Mobile stations2 of the maritime mobile service may communicate,
for safety purposes, with stations of the aeronautical mobile service. Such
communications shall normally be made on the frequencies authorized, and under the
conditions specified in Section I of Article 31 (see also No. 4.9).
Section III – Aeronautical provisions
30.8 § 8 The procedure specified in this Chapter is obligatory for
communications between stations on board aircraft and stations of the maritime mobile-
satellite service, wherever this service or stations of this service are specifically
mentioned.
30.9 § 9 Certain provisions of this Chapter are applicable to the aeronautical
mobile service, except in the case of special arrangements between the governments
concerned.
30.10 § 10 Mobile stations of the aeronautical mobile service may communicate,
for distress and safety purposes, with stations of the maritime mobile service in
conformity with the provisions of this Chapter.
30.11 § 11 Any station on board an aircraft required by national or international
regulations to communicate for distress, urgency or safety purposes with stations of the
maritime mobile service that comply with the provisions of this Chapter, shall be
capable of transmitting and receiving class J3E emissions when using the carrier
frequency 2 182 kHz, or class J3E emissions when using the carrier frequency
4 125 kHz, or class G3E emissions when using the frequency 156.8 MHz and,
optionally, the frequency 156.3 MHz.
_______________
1 30.6.1 The term “rescue coordination centre”, as defined in the International Convention
on Maritime Search and Rescue (1979) refers to a unit responsible for promoting the efficient
organization of search and rescue services and for coordinating the conduct of search and rescue
operations within a search and rescue region.
2 30.7.1 Mobile stations communicating with the stations of the aeronautical mobile (R)
service in bands allocated to the aeronautical mobile (R) service shall conform to the provisions
of the Regulations which relate to that service and, as appropriate, to any special arrangements
between the governments concerned by which the aeronautical mobile (R) service is regulated.
84 Maritime Manual
30.11A § 11A Aircraft, when conducting search and rescue operations, are also
permitted to operate digital selective calling (DSC) equipment on the VHF DSC
frequency 156.525 MHz, and automatic identification system (AIS) equipment on the
AIS frequencies 161.975 MHz and 162.025 MHz. (WRC-07)
Section IV – Land mobile provisions
30.12 § 12 Stations of the land mobile service in uninhabited, sparsely populated
or remote areas may, for distress and safety purposes, use the frequencies provided for
in this Chapter.
30.13 § 13 The procedure specified in this Chapter is obligatory for stations of
the land mobile service when using frequencies provided in these Regulations for
distress and safety communications.
Part B – SECTION I – RR31 85
ARTICLE 31
Frequencies for the global maritime distress and safety system
(GMDSS)
Section I – General
31.1 § 1 The frequencies to be used for the transmission of distress and safety
information under the GMDSS are contained in Appendix 15. In addition to the
frequencies listed in Appendix 15, ship stations and coast stations should use other
appropriate frequencies for the transmission of safety messages and general
radiocommunications to and from shore-based radio systems or networks. (WRC-07)
31.2 § 2 Any emission causing harmful interference to distress and safety
communications on any of the discrete frequencies identified in Appendix 15 is
prohibited. (WRC-07)
31.3 § 3 The number and duration of test transmissions shall be kept to a
minimum on the frequencies identified in Appendix 15; they should be coordinated
with a competent authority, as necessary, and, wherever practicable, be carried out on
artificial antennas or with reduced power. However, testing on the distress and safety
calling frequencies should be avoided, but where this is unavoidable, it should be
indicated that these are test transmissions.
31.4 § 4 Before transmitting for other than distress purposes on any of the
frequencies identified in Appendix 15 for distress and safety, a station shall, where
practicable, listen on the frequency concerned to make sure that no distress transmission
is being sent.
Section II – Survival craft stations
31.6 § 5 1) Equipment for radiotelephony use in survival craft stations shall,
if capable of operating on any frequency in the bands between 156 MHz and 174 MHz,
be able to transmit and receive on 156.8 MHz and at least one other frequency in these
bands.
31.7 2) Equipment for transmitting locating signals from survival craft
stations shall be capable of operating in the 9 200-9 500 MHz band.
86 Maritime Manual
31.8 3) Equipment with digital selective calling facilities for use in
survival craft shall, if capable of operating:
31.9 a) in the bands between 1 606.5 kHz and 2 850 kHz, be able to transmit
on 2 187.5 kHz; (WRC-03)
31.10 b) in the bands between 4 000 kHz and 27 500 kHz, be able to transmit
on 8 414.5 kHz;
31.11 c) in the bands between 156 MHz and 174 MHz, be able to transmit on
156.525 MHz.
Section III – Watchkeeping
31.12 A – Coast stations
31.13 § 6 Those coast stations assuming a watch-keeping responsibility in the
GMDSS shall maintain an automatic digital selective calling watch on frequencies and
for periods of time as indicated in the information published in the List of Coast
Stations and Special Service Stations (List IV). (WRC-07)
31.14 B – Coast earth stations
31.15 § 7 Those coast earth stations assuming a watch-keeping responsibility in
the GMDSS shall maintain a continuous automatic watch for appropriate distress alerts
relayed by space stations.
31.16 C – Ship stations
31.17 § 8 1) Ship stations, where so equipped, shall, while at sea, maintain an
automatic digital selective calling watch on the appropriate distress and safety calling
frequencies in the frequency bands in which they are operating. Ship stations, where so
equipped, shall also maintain watch on the appropriate frequencies for the automatic
reception of transmissions of meteorological and navigational warnings and other
urgent information to ships. (WRC-07)
31.18 2) Ship stations complying with the provisions of this Chapter
should, where practicable, maintain a watch on the frequency 156.8 MHz (VHF
channel 16). (WRC-07)
31.19 D – Ship earth stations
31.20 § 9 Ship earth stations complying with the provisions of this Chapter
shall, while at sea, maintain watch except when communicating on a working channel.
Part B – SECTION I – RR32 87
ARTICLE 32
Operational procedures for distress communications in the
global maritime distress and safety system (GMDSS)* (WRC-07)
Section I – General
32.1 § 1 Distress communications rely on the use of terrestrial MF, HF and
VHF radiocommunications and communications using satellite techniques. Distress
communications shall have absolute priority over all other transmissions. The following
terms apply:
a) The distress alert is a digital selective call (DSC) using a distress call
format, in the bands used for terrestrial radiocommunication, or a
distress message format, in which case it is relayed through space
stations.
b) The distress call is the initial voice or text procedure.
c) The distress message is the subsequent voice or text procedure.
d) The distress alert relay is a DSC transmission on behalf of another
station.
e) The distress call relay is the initial voice or text procedure for a
station not itself in distress. (WRC-07)
32.2 § 2 1) The distress alert shall be sent through a satellite either with
absolute priority in general communication channels, on exclusive distress and safety
frequencies reserved for satellite EPIRBs in the Earth-to-space direction or on the
distress and safety frequencies designated in the MF, HF and VHF bands for digital
selective calling (see Appendix 15). (WRC-07)
32.2A 1A) The distress call shall be sent on the distress and safety
frequencies designated in the MF, HF and VHF bands for radiotelephony. (WRC-07)
32.3 2) The distress alert or call and subsequent messages shall be sent
only on the authority of the person responsible for the ship, aircraft or other vehicle
carrying the mobile station or the mobile earth station. (WRC-07)
32.4 § 3 All stations which receive a distress alert or call transmitted on the
distress and safety frequencies in the MF, HF and VHF bands shall immediately cease
any transmission capable of interfering with distress traffic and prepare for subsequent
distress traffic. (WRC-07)
_______________
* Note by the Secretariat: The title has been aligned in accordance with WRC-07 decisions.
88 Maritime Manual
32.5 § 4 Distress alerts or distress alert relays using DSC should use the
technical structures and content set forth in the most recent version of
Recommendations ITU-R M.493 and ITU-R M.541. (WRC-07)
32.5A § 4A Each administration shall ensure that suitable arrangements are made
for assigning and registering identities used by ships participating in the GMDSS, and
shall make registration information available to rescue coordination centres on a
24-hour day, 7-day week basis. Where appropriate, administrations shall notify
responsible organizations immediately of additions, deletions and other changes in
these assignments (see Nos. 19.39, 19.96 and 19.99). Registration information
submitted shall be in accordance with Resolution 340 (WRC-97)*. (WRC-07)
32.5B § 4B Any GMDSS shipboard equipment which is capable of transmitting
position coordinates as part of a distress alert and which does not have an integral
electronic position-fixing system receiver shall be interconnected to a separate
navigation receiver, if one is installed, to provide that information
automatically. (WRC-07)
32.6 § 5 Transmissions by radiotelephony shall be made slowly and distinctly,
each word being clearly pronounced to facilitate transcription.
32.7 § 6 The phonetic alphabet and figure code in Appendix 14 and the
abbreviations and signals in accordance with the most recent version of
Recommendation ITU-R M.1172 should be used where applicable1. (WRC-03)
Section II – Distress alerting and distress calling (WRC-07)
32.8 A – General
32.9 § 7 1) The transmission of a distress alert or a distress call indicates that
a mobile unit2 or person3 is threatened by grave and imminent danger and requires
immediate assistance. (WRC-07)
_______________
* Note by the Secretariat: This Resolution has been suppressed by WRC-07. The subject
matter is now covered by Resolution 355 (WRC-07).
1 32.7.1 The use of the Standard Marine Communication Phrases and, where language
difficulties exists, the International Code of Signals, both published by the International
Maritime Organization (IMO), is also recommended.
2 32.9.1 Mobile unit: a ship, aircraft or other vehicle.
3 32.9.2 In this Article, where the case is of a person in distress, the application of the
procedures may require adaptation to meet the needs of the particular circumstances.
Part B – SECTION I – RR32 89
32.10 2) The distress alert shall provide4 the identification of the station in
distress and its position.
32.10A § 7A 1) A distress alert is false if it was transmitted without any
indication that a mobile unit or person was in distress and required immediate
assistance (see No. 32.9). Administrations receiving a false distress alert shall report
this infringement in accordance with Section V of Article 15, if that alert:
a) was transmitted intentionally;
b) was not cancelled in accordance with No. 32.53A and Resolution 349
(WRC-97);
c) could not be verified as a result of either the ship’s failure to keep
watch on appropriate frequencies in accordance with Nos. 31.16 to
31.20, or its failure to respond to calls from an authorized rescue
authority;
d) was repeated; or
e) was transmitted using a false identity.
Administrations receiving such a report shall take appropriate steps to ensure that the
infringement does not recur. No action should normally be taken against any ship or
mariner for reporting and cancelling a false distress alert. (WRC-07)
32.10B 2) Administrations shall take practicable and necessary steps to
ensure the avoidance of false distress alerts, including those transmitted
inadvertently. (WRC-07)
32.11 B – Transmission of a distress alert or a distress call (WRC-07)
B1 – Transmission of a distress alert or a distress call by a ship station
or a ship earth station (WRC-07)
32.12 § 8 Ship-to-shore distress alerts or calls are used to alert rescue
coordination centres via coast stations or coast earth stations that a ship is in distress.
These alerts are based on the use of transmissions via satellites (from a ship earth
station or a satellite EPIRB) and terrestrial services (from ship stations and
EPIRBs). (WRC-07)
_______________
4 32.10.1 The distress alert may also contain information regarding the nature of the
distress, the type of assistance required, the course and speed of the mobile unit, the time that
this information was recorded and any other information which might facilitate rescue.
90 Maritime Manual
32.13 § 9 1) Ship-to-ship distress alerts are used to alert other ships in the
vicinity of the ship in distress and are based on the use of digital selective calling in the
VHF and MF bands. Additionally, the HF band may be used. (WRC-07)
32.13A 2) Ship stations equipped for digital selective calling procedures
may transmit a distress call and distress message immediately following the distress
alert in order to attract attention from as many ship stations as possible. (WRC-07)
32.13B 3) Ship stations not equipped for digital selective calling procedures
shall, where practical, initiate the distress communications by transmitting a radio
telephony distress call and message on the frequency 156.8 MHz (VHF
channel 16). (WRC-07)
32.13BA § 9A The radiotelephone distress signal consists of the word MAYDAY
pronounced as the French expression “m'aider”. (WRC-07)
32.13C § 9B 1) The distress call sent on the frequency 156.8 MHz (VHF
channel 16) shall be given in the following form:
– the distress signal MAYDAY, spoken three times;
– the words THIS IS;
– the name of the vessel in distress, spoken three times;
– the call sign or other identification;
– the MMSI (if the initial alert has been sent by DSC). (WRC-07)
32.13D 2) The distress message which follows the distress call should be
given in the following form:
– the distress signal MAYDAY;
– the name of the vessel in distress;
– the call sign or other identification;
– the MMSI (if the initial alert has been sent by DSC);
– the position, given as the latitude and longitude, or if the latitude and
longitude are not known or if time is insufficient, in relation to a
known geographical location;
– the nature of the distress;
– the kind of assistance required;
– any other useful information. (WRC-07)
Part B – SECTION I – RR32 91
32.13E § 9C DSC procedures use a combination of automated functions and
manual intervention to generate the appropriate distress call format in the most recent
version of Recommendation ITU-R M.541. A distress alert sent by DSC consists of one
or more distress alert attempts in which a message format is transmitted identifying the
station in distress, giving its last recorded position and, if entered, the nature of the
distress. In MF and HF bands, distress alert attempts may be sent as a single-frequency
attempt or a multi-frequency attempt on up to six frequencies within one minute. In
VHF bands, only single-frequency call attempts are used. The distress alert will repeat
automatically at random intervals, a few minutes apart, until an acknowledgement sent
by DSC is received. (WRC-07)
B2 – Transmission of a shore-to-ship distress alert relay or a distress
call relay (WRC-07)
32.14 § 10 1) A station or a rescue coordination centre which receives a
distress alert or call and a distress message shall initiate the transmission of a shore-to-
ship distress alert relay addressed, as appropriate, to all ships, to a selected group of
ships, or to a specific ship, by satellite and/or terrestrial means. (WRC-07)
32.15 2) The distress alert relay and the distress call relay shall contain the
identification of the mobile unit in distress, its position and all other information which
might facilitate rescue. (WRC-07)
B3 – Transmission of a distress alert relay or a distress call relay by a station
not itself in distress (WRC-07)
32.16 § 11 A station in the mobile or mobile-satellite service which learns that a
mobile unit is in distress (for example, by a radio call or by observation) shall initiate
and transmit a distress alert relay or a distress call relay on behalf of the mobile unit in
distress once it has ascertained that any of the following circumstances apply: (WRC-07)
32.17 a) on receiving a distress alert or call which is not acknowledged by a
coast station or another vessel within five minutes (see also Nos. 32.29A and
32.31); (WRC-07)
32.18 b) on learning that the mobile unit in distress is otherwise unable or
incapable of participating in distress communications, if the master or other
person responsible for the mobile unit not in distress considers that further
help is necessary. (WRC-07)
32.19 § 12 1) The distress relay on behalf of a mobile unit in distress shall be
sent in a form appropriate to the circumstances (see Nos. 32.19A to 32.19D) using
either a distress call relay by radiotelephony (see Nos. 32.19D and 32.19E), an
individually addressed distress alert relay by DSC (see No. 32.19B), or a distress
priority message through a ship earth station. (WRC-07)
92 Maritime Manual
32.19A 2) A station transmitting a distress alert relay or a distress call relay
in accordance with Nos. 32.16 to 32.18 shall indicate that it is not itself in
distress. (WRC-07)
32.19B 3) A distress alert relay sent by DSC should use the call format, as
found in the most recent version of Recommendations ITU-R M.493 and ITU-R M.541,
and should preferably be addressed to an individual coast station or rescue coordination
centre5. (WRC-07)
32.19C 4) However, a ship shall not transmit a distress alert relay to all
ships by digital selective calling on the VHF or MF distress frequencies following
receipt of a distress alert sent by digital selective calling by the ship in
distress. (WRC-07)
32.19D 5) When an aural watch is being maintained on shore and reliable
ship-to-shore communications can be established by radiotelephony, a distress call relay
is sent by radiotelephony and addressed to the relevant coast station or rescue
coordination centre6 on the appropriate frequency. (WRC-07)
32.19E 6) The distress call relay sent by radiotelephony should be given in
the following form:
– the distress signal MAYDAY RELAY, spoken three times;
– ALL STATIONS or coast station name, as appropriate, spoken three
times;
– the words THIS IS;
– the name of the relaying station, spoken three times;
– the call sign or other identification of the relaying station;
– the MMSI (if the initial alert has been sent by DSC) of the relaying
station (the vessel not in distress). (WRC-07)
32.19F 7) This call shall be followed by a distress message which shall, as
far as possible, repeat the information7 contained in the original distress alert or distress
message. (WRC-07)
_______________
5 32.19B.1 Vessels making a distress alert relay or a distress call relay should ensure that a
suitable coast station or rescue coordination centre is informed of any distress communications
previously exchanged. (WRC-07)
6 32.19D.1 Vessels making a distress call relay should ensure that a suitable coast station or
rescue coordination centre is informed of any distress communications previously
exchanged. (WRC-07)
7 32.19F.1 If the station in distress cannot be identified, then it will be necessary to originate
the distress message as well, using, for example, terms such as “Unidentified trawler” refer to
the mobile unit in distress. (WRC-07)
Part B – SECTION I – RR32 93
32.19G 8) When no aural watch is being maintained on shore, or there are
other difficulties in establishing reliable ship-to-shore communications by
radiotelephony, an appropriate coast station or rescue coordination centre may be
contacted by sending an individual distress alert relay by DSC, addressed solely to that
station and using the appropriate call formats. (WRC-07)
32.19H 9) In the event of continued failure to contact a coast station or
rescue coordination centre directly, it may be appropriate to send a distress call relay by
radiotelephony addressed to all ships, or to all ships in a certain geographical area. See
also No. 32.19C. (WRC-07)
32.20 C – Receipt and acknowledgement of distress alerts
and distress calls (WRC-07)
C1 – Procedure for acknowledgement of receipt of distress alerts or
a distress call (WRC-07)
32.21 § 13 1) Acknowledgement of receipt of a distress alert, including a
distress alert relay, shall be made in the manner appropriate to the method of
transmission of the alert and within the time-scale appropriate to the role of the station
in receipt of the alert. Acknowledgement by satellite shall be sent
immediately. (WRC-07)
32.21A 2) When acknowledging receipt of a distress alert sent by DSC8, the
acknowledgement in the terrestrial services shall be made by DSC, radiotelephony or
narrow-band direct-printing telegraphy as appropriate to the circumstances, on the
associated distress and safety frequency in the same band in which the distress alert was
received, taking due account of the directions given in the most recent versions of
Recommendations ITU-R M.493 and ITU-R M.541. (WRC-07)
32.21B Acknowledgement by DSC of a distress alert sent by DSC addressed
to stations in the maritime mobile service shall be addressed to all stations8. (WRC-07)
32.23 § 15 1) When acknowledging by radiotelephony the receipt of a distress
alert or a distress call from a ship station or a ship earth station, the acknowledgement
should be given in the following form:
– the distress signal MAYDAY;
_______________
8 32.21A.1 In order to ensure that no unnecessary delay occurs before the shore-based
authorities become aware of a distress incident, the acknowledgement by DSC to a distress alert
sent by DSC shall normally only be made by a coast station or a rescue coordination centre. An
acknowledgement by DSC will cancel any further automated repetition of the distress alert using
DSC. (WRC-07)
94 Maritime Manual
– the name followed by the call sign, or the MMSI or other
identification of the station sending the distress message;
– the words THIS IS;
– the name and call sign or other identification of the station
acknowledging receipt;
– the word RECEIVED;
– the distress signal MAYDAY. (WRC-07)
32.24 2) When acknowledging by narrow-band direct-printing telegraphy
the receipt of a distress alert from a ship station, the acknowledgement should be given
in the following form:
– the distress signal MAYDAY;
– the call sign or other identification of the station sending the distress
alert;
– the word DE;
– the call sign or other identification of the station acknowledging
receipt of the distress alert;
– the signal RRR;
– the distress signal MAYDAY. (WRC-07)
C2 – Receipt and acknowledgement by a coast station, a coast earth station
or a rescue coordination centre (WRC-07)
32.26 § 17 Coast stations and the appropriate coast earth stations in receipt of
distress alerts or distress calls shall ensure that they are routed as soon as possible to a
rescue coordination centre. In addition, receipt of a distress alert or a distress call is to
be acknowledged as soon as possible by a coast station, or by a rescue coordination
centre via a coast station or an appropriate coast earth station. A shore-to-ship distress
alert relay or a distress call relay (see Nos. 32.14 and 32.15) shall also be made when
the method of receipt warrants a broadcast alert to shipping or when the circumstances
of the distress incident indicate that further help is necessary. (WRC-07)
32.27 § 18 A coast station using DSC to acknowledge a distress alert shall
transmit the acknowledgement on the distress calling frequency on which the distress
alert was received and should address it to all ships. The acknowledgement
shall include the identification of the ship whose distress alert is being
acknowledged. (WRC-07)
Part B – SECTION I – RR32 95
C3 – Receipt and acknowledgement by a ship station or ship earth station (WRC-07)
32.28 § 19 1) Ship or ship earth stations in receipt of a distress alert or a
distress call shall, as soon as possible, inform the master or person responsible for the
ship of the contents of the distress alert. (WRC-07)
32.29 2) In areas where reliable communications with one or more coast
stations are practicable, ship stations in receipt of a distress alert or a distress call from
another vessel should defer acknowledgement for a short interval so that a coast station
may acknowledge receipt in the first instance. (WRC-07)
32.29A 3) Ship stations in receipt of a distress call sent by radiotelephony
on the frequency 156.8 MHz (VHF channel 16) shall, if the call is not acknowledged by
a coast station or another vessel within five minutes, acknowledge receipt to the vessel
in distress and use any means available to relay the distress call to an appropriate coast
station or coast earth station (see also Nos. 32.16 to 32.19F). (WRC-07)
32.30 § 20 1) Ship stations operating in areas where reliable communications
with a coast station are not practicable which receive a distress alert or call from a ship
station which is, beyond doubt, in their vicinity, shall, as soon as possible and if
appropriately equipped, acknowledge receipt to the vessel in distress and inform a
rescue coordination centre through a coast station or coast earth station (see also
Nos. 32.16 to 32.19H). (WRC-07)
32.31 2) However in order to avoid making unnecessary or confusing
transmissions in response, a ship station, which may be at a considerable distance from
the incident, receiving an HF distress alert, shall not acknowledge it but shall observe
the provisions of Nos. 32.36 to 32.38, and shall, if the distress alert is not acknowledged
by a coast station within five minutes, relay the distress alert, but only to an appropriate
coast station or coast earth station (see also Nos. 32.16 to 32.19H). (WRC-07)
32.32 § 21 A ship station acknowledging receipt of a distress alert sent by DSC
should, in accordance with No. 32.29 or No. 32.30: (WRC-07)
32.33 a) in the first instance, acknowledge receipt of the distress alert by using
radiotelephony on the distress and safety traffic frequency in the band used for
the alert, taking into account any instructions which may be issued by a
responding coast station; (WRC-07)
32.34 b) if acknowledgement by radiotelephony of the distress alert received
on the MF or VHF distress alerting frequency is unsuccessful, acknowledge
receipt of the distress alert by responding with a digital selective call on the
appropriate frequency.
96 Maritime Manual
32.34A § 21A However, unless instructed to do so by a coast station or a rescue
coordination centre, a ship station may only send an acknowledgement by DSC in the
event that:
a) no acknowledgement by DSC from a coast station has been observed;
and
b) no other communication by radiotelephony or narrow-band direct-
printing telegraphy to or from the vessel in distress has been
observed; and
c) at least five minutes have elapsed and the distress alert by DSC has
been repeated (see No. 32.21A.1). (WRC-07)
32.35 § 22 A ship station in receipt of a shore-to-ship distress alert relay or
distress call relay (see No. 32.14) should establish communication as directed and
render such assistance as required and appropriate. (WRC-07)
32.36 D – Preparations for handling of distress traffic
32.37 § 23 On receipt of a distress alert or a distress call, ship stations and coast
stations shall set watch on the radiotelephone distress and safety traffic frequency
associated with the distress and safety calling frequency on which the distress alert was
received. (WRC-07)
32.38 § 24 Coast stations and ship stations with narrow-band direct-printing
equipment shall set watch on the narrow-band direct-printing frequency associated with
the distress alert if it indicates that narrow-band direct-printing is to be used for
subsequent distress communications. If practicable, they should additionally set watch
on the radiotelephone frequency associated with the distress alert frequency. (WRC-07)
Section III – Distress traffic
32.39 A – General and search and rescue coordinating communications
32.40 § 25 Distress traffic consists of all messages relating to the immediate
assistance required by the ship in distress, including search and rescue communications
and on-scene communications. The distress traffic shall as far as possible be on the
frequencies contained in Article 31.
32.42 § 26 For distress traffic by radiotelephony, when establishing communi-
cations, calls shall be prefixed by the distress signal MAYDAY.
Part B – SECTION I – RR32 97
32.43 § 27 1) Error correction techniques in accordance with relevant ITU-R
Recommendations shall be used for distress traffic by direct-printing telegraphy. All
messages shall be preceded by at least one carriage return, a line feed signal, a letter
shift signal and the distress signal MAYDAY.
32.44 2) Distress communications by direct-printing telegraphy should
normally be established by the ship in distress and should be in the broadcast (forward
error correction) mode. The ARQ mode may subsequently be used when it is
advantageous to do so.
32.45 § 28 1) The rescue coordination centre responsible for controlling a
search and rescue operation shall also coordinate the distress traffic relating to the
incident or may appoint another station to do so. (WRC-07)
32.46 2) The rescue coordination centre coordinating distress traffic, the
unit coordinating search and rescue operations9 or the coast station involved may
impose silence on stations which interfere with that traffic. This instruction shall be
addressed to all stations or to one station only, according to circumstances. In either
case, the following shall be used:
32.47 a) in radiotelephony, the signal SEELONCE MAYDAY, pronounced as
the French expression “silence, m'aider”;
32.48 b) in narrow-band direct-printing telegraphy normally using forward-
error correcting mode, the signal SILENCE MAYDAY. However, the ARQ
mode may be used when it is advantageous to do so.
32.49 § 29 Until they receive the message indicating that normal working may
be resumed (see No. 32.51), all stations which are aware of the distress traffic, and
which are not taking part in it, and which are not in distress, are forbidden to transmit
on the frequencies in which the distress traffic is taking place.
32.50 § 30 A station of the mobile service which, while following distress traffic,
is able to continue its normal service, may do so when the distress traffic is well
established and on condition that it observes the provisions of No. 32.49 and that it does
not interfere with distress traffic.
32.51 § 31 When distress traffic has ceased on frequencies which have been used
for distress traffic, the station controlling the search and rescue operation shall initiate a
message for transmission on these frequencies indicating that distress traffic has
finished. (WRC-07)
_______________
9 32.46.1 In accordance with the International Convention on Maritime Search and Rescue
(1979) this is the on-scene commander (OSC) or the coordinator surface search (CSS).
98 Maritime Manual
32.52 § 32 1) In radiotelephony, the message referred to in No. 32.51 should
consist of:
– the distress signal MAYDAY;
– the call “ALL STATIONS”, spoken three times;
– the words THIS IS;
– the name of the station sending that message, spoken three times;
– the call sign or other identification of the station sending the message;
– the time of handing in of the message;
– the MMSI (if the initial alert has been sent by DSC), the name and the
call sign of the mobile station which was in distress;
– the words SEELONCE FEENEE pronounced as the French words
“silence fini”. (WRC-07)
32.53 2) In direct-printing telegraphy, the message referred to in
No. 32.51 consists of:
– the distress signal MAYDAY;
– the call CQ;
– the word DE;
– the call sign or other identification of the station sending the message;
– the time of handing in of the message;
– the name and call sign of the mobile station which was in distress;
and
– the words SILENCE FINI.
32.53A Cancellation of an inadvertent distress alert (WRC-07)
32.53B § 32A 1) A station transmitting an inadvertent distress alert or call shall
cancel the transmission. (WRC-07)
32.53C 2) An inadvertent DSC alert shall be cancelled by DSC, if the DSC
equipment is so capable. The cancellation should be in accordance with the most recent
version of Recommendation ITU-R M.493. In all cases, cancellations shall also be
transmitted by radiotelephone in accordance with 32.53E. (WRC-07)
32.53D 3) An inadvertent distress call shall be cancelled by radiotelephone
in accordance with the procedure in 32.53E. (WRC-07)
Part B – SECTION I – RR32 99
32.53E 4) Inadvertent distress transmissions shall be cancelled orally on the
associated distress and safety frequency in the same band on which the distress
transmission was sent, using the following procedure:
– the call “ALL STATIONS”, spoken three times;
– the words THIS IS;
– the name of the vessel, spoken three times;
– the call sign or other identification;
– the MMSI (if the initial alert has been sent by DSC);
– PLEASE CANCEL MY DISTRESS ALERT OF time in UTC.
Monitor the same band on which the inadvertent distress transmission was sent
and respond to any communications concerning that distress transmission as
appropriate. (WRC-07)
32.54 B – On-scene communications
32.55 § 33 1) On-scene communications are those between the mobile unit in
distress and assisting mobile units, and between the mobile units and the unit
coordinating search and rescue operations9.
32.56 2) Control of on-scene communications is the responsibility of the
unit coordinating search and rescue operations9. Simplex communications shall be used
so that all on-scene mobile stations may share relevant information concerning the
distress incident. If direct-printing telegraphy is used, it shall be in the forward error-
correcting mode.
32.57 § 34 1) The preferred frequencies in radiotelephony for on-scene
communications are 156.8 MHz and 2 182 kHz. The frequency 2 174.5 kHz may also be
used for ship-to-ship on-scene communications using narrow-band direct-printing
telegraphy in the forward error correcting mode.
32.58 2) In addition to 156.8 MHz and 2 182 kHz, the frequencies
3 023 kHz, 4 125 kHz, 5 680 kHz, 123.1 MHz and 156.3 MHz may be used for ship-to-
aircraft on-scene communications.
32.59 § 35 The selection or designation of on-scene frequencies is the
responsibility of the unit coordinating search and rescue operations9. Normally, once an
on-scene frequency is established, a continuous aural or teleprinter watch is maintained
by all participating on-scene mobile units on the selected frequency.
_______________
9 32.55.1, 32.56.1 and 32.59.1 In accordance with the International Convention on
Maritime Search and Rescue (1979) this is the on-scene commander (OSC) or the coordinator
surface search (CSS).
100 Maritime Manual
32.60 C – Locating and homing signals
32.61 § 36 1) Locating signals are radio transmissions intended to facilitate the
finding of a mobile unit in distress or the location of survivors. These signals include
those transmitted by searching units, and those transmitted by the mobile unit in
distress, by survival craft, by float-free EPIRBs, by satellite EPIRBs and by search and
rescue radar transponders to assist the searching units.
32.62 2) Homing signals are those locating signals which are transmitted
by mobile units in distress, or by survival craft, for the purpose of providing searching
units with a signal that can be used to determine the bearing to the transmitting stations.
32.63 3) Locating signals may be transmitted in the following frequency
bands:
117.975-137 MHz;
156-174 MHz;
406-406.1 MHz; and
9 200-9 500 MHz. (WRC-07)
Part B – SECTION I – RR33 101
ARTICLE 33
Operational procedures for urgency and safety communications in
the global maritime distress and safety system (GMDSS)
Section I – General
33.1 § 1 1) Urgency and safety communications include: (WRC-07)
33.2 a) navigational and meteorological warnings and urgent information;
33.3 b) ship-to-ship safety of navigation communications;
33.4 c) ship reporting communications;
33.5 d) support communications for search and rescue operations;
33.6 e) other urgency and safety messages; and
33.7 f ) communications relating to the navigation, movements and needs of
ships and weather observation messages destined for an official meteorological
service.
33.7A 2) Urgency communications shall have priority over all other
communications, except distress. (WRC-07)
33.7B 3) Safety communications shall have priority over all other
communications, except distress and urgency. (WRC-07)
Section II – Urgency communications
33.7C § 1A The following terms apply:
a) The urgency announcement is a digital selective call using an urgency
call format1, in the bands used for terrestrial radiocommunication, or an
urgency message format, in which case it is relayed through space stations.
b) The urgency call is the initial voice or text procedure.
c) The urgency message is the subsequent voice or text
procedure. (WRC-07)
_______________
1 33.7C.1 The format of urgency calls and urgency messages should be in accordance with
the relevant ITU-R Recommendations. (WRC-07)
102 Maritime Manual
33.8 § 2 1) In a terrestrial system, urgency communications consist of an
announcement, transmitted using digital selective calling, followed by the urgency call
and message transmitted using radiotelephony, narrow-band direct-printing, or data.
The announcement of the urgency message shall be made on one or more of the distress
and safety calling frequencies specified in Section I of Article 31 using either digital
selective calling and the urgency call format, or if not available, radio telephony
procedures and the urgency signal. Announcements using digital selective calling
should use the technical structure and content set forth in the most recent version of
Recommendations ITU-R M.493 and ITU-R M.541. A separate announcement need not
be made if the urgency message is to be transmitted through the maritime mobile-
satellite service. (WRC-07)
33.8A 2) Ship stations not equipped for digital selective calling procedures
may announce an urgency call and message by transmitting the urgency signal by
radiotelephony on the frequency 156.8 MHz (channel 16), while taking into account
that other stations outside VHF range may not receive the announcement. (WRC-07)
33.8B 3) In the maritime mobile service, urgency communications may be
addressed either to all stations or to a particular station. When using digital selective
calling techniques, the urgency announcement shall indicate which frequency is to be
used to send the subsequent message and, in the case of a message to all stations, shall
use the “All Ships” format setting. (WRC-07)
33.8C 4) Urgency announcements from a coast station may also be
directed to a group of vessels or to vessels in a defined geographical area. (WRC-07)
33.9 § 3 1) The urgency call and message shall be transmitted on one or
more of the distress and safety traffic frequencies specified in Section I of
Article 31. (WRC-07)
33.9A 2) However, in the maritime mobile service, the urgency message
shall be transmitted on a working frequency:
a) in the case of a long message or a medical call; or
b) in areas of heavy traffic when the message is being repeated.
An indication to this effect shall be included in the urgency announcement or
call. (WRC-07)
33.9B 3) In the maritime mobile-satellite service, a separate urgency
announcement or call does not need to be made before sending the urgency message.
However, if available, the appropriate network priority access settings should be used
for sending the message. (WRC-07)
Part B – SECTION I – RR33 103
33.10 § 4 The urgency signal consists of the words PAN PAN. In
radiotelephony each word of the group shall be pronounced as the French word
“panne”.
33.11 § 5 1) The urgency call format and the urgency signal indicate that the
calling station has a very urgent message to transmit concerning the safety of a mobile
unit or a person. (WRC-07)
33.11A 2) Communications concerning medical advice may be preceded by
the urgency signal. Mobile stations requiring medical advice may obtain it through any
of the land stations shown in the List of Coast Stations and Special Service
Stations. (WRC-07)
33.11B 3) Urgency communications to support search and rescue
operations need not be preceded by the urgency signal. (WRC-07)
33.12 § 6 1) The urgency call should consist of:
– the urgency signal PAN PAN, spoken three times;
– the name of the called station or “all stations”, spoken three times;
– the words THIS IS;
– the name of the station transmitting the urgency message, spoken
three times;
– the call sign or any other identification;
– the MMSI (if the initial announcement has been sent by DSC),
followed by the urgency message or followed by the details of the channel to be used
for the message in the case where a working channel is to be used.
In radiotelephony, on the selected working frequency, the urgency call and message
consists of:
– the urgency signal PAN PAN, spoken three times;
– the name of the called station or “all stations”, spoken three times;
– the words THIS IS;
– the name of the station transmitting the urgency message, spoken
three times;
– the call sign or any other identification;
– the MMSI (if the initial announcement has been sent by DSC);
– the text of the urgency message. (WRC-07)
104 Maritime Manual
33.13 2) In narrow-band direct-printing, the urgency message shall be
preceded by the urgency signal (see No. 33.10) and the identification of the transmitting
station.
33.14 § 7 1) The urgency call format or urgency signal shall be sent only on
the authority of the person responsible for the ship, aircraft or other vehicle carrying the
mobile station or mobile earth station. (WRC-07)
33.15 2) The urgency call format or the urgency signal may be transmitted
by a land station or a coast earth station with the approval of the responsible authority.
33.15A § 7A 1) Ship stations in receipt of an urgency announcement or call
addressed to all stations shall not acknowledge. (WRC-07)
33.15B 2) Ship stations in receipt of an urgency announcement or call of an
urgency message shall monitor the frequency or channel indicated for the message for
at least five minutes. If, at the end of the five-minute monitoring period, no urgency
message has been received, a coast station should, if possible, be notified of the missing
message. Thereafter, normal working may be resumed. (WRC-07)
33.15C 3) Coast and ship stations which are in communication on
frequencies other than those used for the transmission of the urgency signal or the
subsequent message may continue their normal work without interruption, provided that
the urgency message is not addressed to them nor broadcast to all stations. (WRC-07)
33.16 § 8 When an urgency announcement or call and message was transmitted
to more than one station and action is no longer required, an urgency cancellation
should be sent by the station responsible for its transmission.
The urgency cancellation should consist of:
– the urgency signal PAN PAN, spoken three times;
– “all stations”, spoken three times;
– the words THIS IS;
– the name of the station transmitting the urgency message, spoken
three times;
– the call sign or any other identification;
– the MMSI (if the initial announcement has been sent by DSC);
– PLEASE CANCEL URGENCY MESSAGE OF time in UTC. (WRC-07)
Part B – SECTION I – RR33 105
33.17 § 9 1) Error correction techniques in accordance with relevant ITU-R
Recommendations shall be used for urgency messages by direct-printing telegraphy. All
messages shall be preceded by at least one carriage return, a line feed signal, a letter
shift signal and the urgency signal PAN PAN.
33.18 2) Urgency communications by direct-printing telegraphy should
normally be established in the broadcast (forward error correction) mode. The ARQ
mode may subsequently be used when it is advantageous to do so.
Section III – Medical transports
33.19 § 10 The term “medical transports”, as defined in the 1949 Geneva
Conventions and Additional Protocols, refers to any means of transportation by land,
water or air, whether military or civilian, permanent or temporary, assigned exclusively
to medical transportation and under the control of a competent authority of a party to a
conflict or of neutral States and of other States not parties to an armed conflict, when
these ships, craft and aircraft assist the wounded, the sick and the shipwrecked.
33.20 § 11 1) For the purpose of announcing and identifying medical transports
which are protected under the above-mentioned Conventions, the procedure of
Section II of this Article is used. The urgency call shall be followed by the
addition of the single word MEDICAL in narrow-band direct-printing and by the
addition of the single word MAY-DEE-CAL pronounced as in French “médical”, in
radiotelephony. (WRC-07)
33.20A 2) When using digital selective calling techniques, the urgency
announcement on the appropriate Digital Selective Calling distress and safety
frequencies shall always be addressed to all stations on VHF and to a specified
geographical area on MF and HF and shall indicate “Medical transport” in accordance
with the most recent version of Recommendations ITU-R M.493 and
ITU-R M.541. (WRC-07)
33.20B 3) Medical transports may use one or more of the distress and safety
traffic frequencies specified in Section I of Article 31 for the purpose of self-
identification and to establish communications. As soon as practicable, communications
shall be transferred to an appropriate working frequency. (WRC-07)
33.21 § 12 The use of the signals described in Nos. 33.20 and 33.20A indicates
that the message which follows concerns a protected medical transport. The message
shall convey the following data: (WRC-07)
33.22 a) call sign or other recognized means of identification of the medical
transport;
33.23 b) position of the medical transport;
106 Maritime Manual
33.24 c) number and type of vehicles in the medical transport;
33.25 d) intended route;
33.26 e) estimated time en route and of departure and arrival, as appropriate;
33.27 f ) any other information, such as flight altitude, radio frequencies
guarded, languages used and secondary surveillance radar modes and codes.
33.30 § 14 The use of radiocommunications for announcing and identifying
medical transports is optional; however, if they are used, the provisions of these
Regulations and particularly of this Section and of Articles 30 and 31 shall apply.
Section IV – Safety communications
33.30A § 14A The following terms apply:
a) the safety announcement is a digital selective call using a safety call
format in the bands used for terrestrial radiocommunication or a safety
message format, in which case it is relayed through space stations;
b) the safety call is the initial voice or text procedure;
c) the safety message is the subsequent voice or text
procedure. (WRC-07)
33.31 § 15 1) In a terrestrial system, safety communications consist of a safety
announcement, transmitted using digital selective calling, followed by the safety call
and message transmitted using radiotelephony, narrow-band direct-printing or data. The
announcement of the safety message shall be made on one or more of the distress and
safety calling frequencies specified in Section I of Article 31 using either digital
selective calling techniques and the safety call format, or radiotelephony procedures
and the safety signal. (WRC-07)
33.31A 2) However, in order to avoid unnecessary loading of the distress
and safety calling frequencies specified for use with digital selective calling techniques:
a) safety messages transmitted by coast stations in accordance with a
predefined timetable should not be announced by digital selective calling
techniques;
b) safety messages which only concern vessels sailing in the vicinity
should be announced using radiotelephony procedures. (WRC-07)
Part B – SECTION I – RR33 107
33.31B 3) In addition, ship stations not equipped for digital selective calling
procedures may announce a safety message by transmitting the safety call by
radiotelephony. In such cases the announcement shall be made using the frequency
156.8 MHz (VHF channel 16), while taking into account that other stations outside
VHF range may not receive the announcement. (WRC-07)
33.31C 4) In the maritime mobile service, safety messages shall generally
be addressed to all stations. In some cases, however, they may be addressed to a
particular station. When using digital selective calling techniques, the safety
announcement shall indicate which frequency is to be used to send the subsequent
message and, in the case of a message to all stations, shall use the “All Ships” format
setting. (WRC-07)
33.32 § 16 1) In the maritime mobile service, the safety message shall, where
practicable, be transmitted on a working frequency in the same band(s) as those used
for the safety announcement or call. A suitable indication to this effect shall be made at
the end of the safety call. In the case that no other option is practicable, the safety
message may be sent by radiotelephony on the frequency 156.8 MHz (VHF
channel 16). (WRC-07)
33.32A 2) In the maritime mobile-satellite service, a separate safety
announcement or call does not need to be made before sending the safety message.
However, if available, the appropriate network priority access settings should be used
for sending the message. (WRC-07)
33.33 § 17 The safety signal consists of the word SECURITE. In radiotelephony,
it shall be pronounced as in French.
33.34 § 18 1) The safety call format or the safety signal indicates that the
calling station has an important navigational or meteorological warning to
transmit. (WRC-07)
33.34A 2) Messages from ship stations containing information concerning
the presence of cyclones shall be transmitted, with the least possible delay, to other
mobile stations in the vicinity and to the appropriate authorities through a coast station,
or through a rescue coordination centre via a coast station or an appropriate coast earth
station. These transmissions shall be preceded by the safety announcement or
call. (WRC-07)
33.34B 3) Messages from ship stations, containing information on the
presence of dangerous ice, dangerous wrecks, or any other imminent danger to marine
navigation, shall be transmitted as soon as possible to other ships in the vicinity, and to
the appropriate authorities through a coast station, or through a rescue coordination
centre via a coast station or an appropriate coast earth station. These transmissions shall
be preceded by the safety announcement or call. (WRC-07)
108 Maritime Manual
33.35 § 19 1) The complete safety call should consist of:
– the safety signal SECURITE, spoken three times;
– the name of the called station or “all stations”, spoken three times;
– the words THIS IS;
– the name of the station transmitting the safety message, spoken three
times;
– the call sign or any other identification;
– the MMSI (if the initial announcement has been sent by DSC),
followed by the safety message or followed by the details of the channel to be used for
the message in the case where a working channel is to be used.
In radiotelephony, on the selected working frequency, the safety call and message
should consist of:
– the safety signal SECURITE, spoken three times;
– the name of the called station or “all stations”, spoken three times;
– the words THIS IS;
– the name of the station transmitting the safety message, spoken three
times;
– the call sign or any other identification;
– the MMSI (if the initial alert has been sent by DSC);
– the text of the safety message. (WRC-07)
33.36 2) In narrow-band direct-printing, the safety message shall be
preceded by the safety signal (see No. 33.33), and the identification of the transmitting
station.
33.37 § 20 1) Error correction techniques in accordance with relevant ITU-R
Recommendations shall be used for safety messages by direct-printing telegraphy. All
messages shall be preceded by at least one carriage return, a line feed signal, a letter
shift signal and the safety signal SECURITE.
33.38 2) Safety communications by direct-printing telegraphy should
normally be established in the broadcast (forward error correction) mode. The ARQ
mode may subsequently be used when it is advantageous to do so.
33.38A § 20A 1) Ship stations in receipt of a safety announcement using digital
selective calling techniques and the “All Ships” format setting, or otherwise addressed
to all stations, shall not acknowledge. (WRC-07)
Part B – SECTION I – RR33 109
33.38B 2) Ship stations in receipt of a safety announcement or safety call
and message shall monitor the frequency or channel indicated for the message and shall
listen until they are satisfied that the message is of no concern to them. They shall not
make any transmission likely to interfere with the message. (WRC-07)
Section V – Transmission of maritime safety information2
33.39 A – General
33.41 § 22 The mode and format of the transmissions mentioned in Nos. 33.43,
33.45, 33.46 and 33.48 shall be in accordance with the relevant ITU-R
Recommendations.
33.42 B – International NAVTEX system
33.43 § 23 Maritime safety information shall be transmitted by means of
narrow-band direct-printing telegraphy with forward error correction using the
frequency 518 kHz in accordance with the international NAVTEX system (see
Appendix 15).
33.44 C – 490 kHz and 4 209.5 kHz
33.45 § 24 1) The frequency 490 kHz may be used for the transmission of
maritime safety information by means of narrow-band direct-printing telegraphy with
forward error correction (see Appendix 15). (WRC-03)
33.46 2) The frequency 4 209.5 kHz is used exclusively for NAVTEX-
type transmission by means of narrow-band direct-printing telegraphy with forward
error correction.
33.47 D – High seas maritime safety information
33.48 § 25 Maritime safety information is transmitted by means of narrow-band
direct-printing telegraphy with forward error correction using the frequencies
4 210 kHz, 6 314 kHz, 8 416.5 kHz, 12 579 kHz, 16 806.5 kHz, 19 680.5 kHz,
22 376 kHz and 26 100.5 kHz.
_______________
2 33.V.1 Maritime safety information includes navigation and meteorological warnings,
meteorological forecasts and other urgent messages pertaining to safety transmitted from coast
stations or coast earth stations. (WRC-07)
110 Maritime Manual
33.49 E – Maritime safety information via satellite
33.50 § 26 Maritime safety information may be transmitted via satellite in the
maritime mobile-satellite service using the band 1 530-1 545 MHz (see Appendix 15).
Section VI – Intership navigation safety communications
33.51 § 27 1) Intership navigation safety communications are those VHF radio-
telephone communications conducted between ships for the purpose of contributing to
the safe movement of ships.
33.52 2) The frequency 156.650 MHz is used for intership navigation
safety communications (see also Appendix 15 and note k) in Appendix 18).
Section VII – Use of other frequencies for safety (WRC-07)
33.53 § 28 Radiocommunications for safety purposes concerning ship reporting
communications, communications relating to the navigation, movements and needs of
ships and weather observation messages may be conducted on any appropriate
communications frequency, including those used for public correspondence. In
terrestrial systems, the bands 415-535 kHz (see Article 52), 1 606.5-4 000 kHz (see
Article 52), 4 000-27 500 kHz (see Appendix 17), and 156-174 MHz (see Appendix 18)
are used for this function. In the maritime mobile-satellite service, frequencies in the
bands 1 530-1 544 MHz and 1 626.5-1 645.5 MHz are used for this function as well as
for distress alerting purposes (see No. 32.2). (WRC-07)
Part B – SECTION I – RR34 111
ARTICLE 34
Alerting signals in the global maritime distress and safety system
(GMDSS)
Section I – Emergency position-indicating radiobeacon (EPIRB) and
satellite EPIRB signals
34.1 § 1 The emergency position-indicating radiobeacon signal in the band
406-406.1 MHz shall be in accordance with Recommendation ITU-R
M.633-3. (WRC-07)
Section II – Digital selective calling
34.2 § 2 The characteristics of the “distress call” (see No. 32.9) in the digital
selective calling system shall be in accordance with relevant ITU-R Recommendations
(see Resolution 27 (Rev.WRC-03)*).
_______________
* Note by the Secretariat: This Resolution was revised by WRC-07.
112 Maritime Manual – SECTION I – RR46
ARTICLE 46
Authority of the master
46.1 § 1 The service of a ship station is placed under the supreme authority of
the master or of the person responsible for the ship or other vessel carrying the station.
46.2 § 2 The person holding this authority shall require that each operator
comply with these Regulations and that the ship station for which the operator is
responsible is used, at all times, in accordance with these Regulations.
46.3 § 3 The master or the person responsible, as well as all persons who may
have knowledge of the text or even of the existence of a radiotelegram, or of any
information whatever obtained by means of the radiocommunication service, are placed
under the obligation of observing and ensuring the secrecy of correspondence.
46.4 § 4 The provisions of Nos. 46.1, 46.2 and 46.3 shall also apply to
personnel of ship earth stations.
Part B – SECTION I – RR47 113
ARTICLE 47
Operator’s certificates
Section I – General provisions
47.2 § 1 1) The service of every ship radiotelephone station, ship earth
station and ship station using the frequencies and techniques for GMDSS, as prescribed
in Chapter VII, shall be controlled by an operator holding a certificate issued or
recognized by the government to which the station is subject. Provided the station is so
controlled, other persons besides the holder of the certificate may use the
equipment. (WRC-07)
47.4 2) Nevertheless, in the service of radiotelephone stations operating
solely on frequencies above 30 MHz, each government shall decide for itself whether a
certificate is necessary and, if so, shall define the conditions for obtaining it.
47.5 3) The provisions of No. 47.4 shall not, however, apply to any ship
station working on frequencies assigned for international use.
47.9 § 3 1) Each administration shall take the necessary steps to prevent, to
the maximum extent possible, the fraudulent use of certificates. For this purpose, such
certificates shall bear the holder’s signature and shall be authenticated by the issuing
administration. Administrations may employ, if they wish, other means of identification
such as photographs, fingerprints, etc.
47.10 2) In the maritime mobile service the certificates issued after
1 January 1978 shall bear the photograph of the holder and the holder’s date of birth.
47.11 3) To facilitate verification of certificates, these may carry, if
necessary, in addition to the text in the national language, a translation of this text in a
working language of the Union.
47.12 4) In the maritime mobile service all certificates not in one of the
working languages of the Union and issued after 1 January 1978 shall carry at least the
following information in one of these working languages:
47.13 a) the name and date of birth of the holder;
47.14 b) the title of the certificate and its date of issue;
114 Maritime Manual
47.15 c) if applicable, the number and period of validity of the certificate;
47.16 d) the issuing administration.
47.17 § 4 Each administration shall take the necessary steps to place operators
under the obligation to preserve the secrecy of correspondence as provided for in
No. 18.4.
47.18 § 5 1) Each administration may determine the conditions under which
personnel holding certificates specified in Section II may be granted certificates
specified in Nos. 47.20 to 47.23B. (WRC-07)
47.18A 2) Each administration may determine the conditions under which
personnel holding certificates for equipment that operate with non-GMDSS frequencies
and techniques may be granted certificates specified in Nos. 47.26 and 47.27. (WRC-07)
Section II – Categories of operator’s certificates
A − GMDSS certificates (WRC-07)
47.19 § 6 1) There are six categories of certificates, shown in descending
order of requirements, for personnel of ship stations and ship earth stations using the
frequencies and techniques prescribed in Chapter VII. An operator meeting the
requirements of a certificate automatically meets all of the requirements of lower order
certificates. (WRC-07)
47.20 a) First-class radio electronic certificate.
47.21 b) Second-class radio electronic certificate.
47.22 c) General operator’s certificate.
47.23 d) Restricted operator’s certificate.
47.23A e) Long range certificate (for non-SOLAS vessels). (WRC-07)
47.23B f) Short range certificate (for non-SOLAS vessels). (WRC-07)
Part B – SECTION I – RR47 115
47.24 2) The holder of one of the certificates specified in Nos. 47.20 to
47.23 may carry out the service of ship stations or ship earth stations using the
frequencies and techniques prescribed in Chapter VII.
B − Non-GMDSS certificates (WRC-07)
47.25 § 7 1) There are six categories of certificates. Existing certificates of the
categories listed in No. 47.26 may continue to be used for the purposes they were issued
for. (WRC-07)
47.26 § 8 The following maritime radio operator’s certificates are still valid:
1 Radiocommunication operator’s general certificate.
2 First-class radio telegraph operator’s certificate.
3 Second-class radio telegraph operator’s certificate.
4 Radiotelegraph operator’s special certificate.
5 Radiotelephone operator’s general certificate.
6 Restricted radiotelephone operator’s certificate. (WRC-07)
47.27 § 9 The requirements for the certificates of this section, for which
candidates must show proof of technical and professional knowledge and qualification,
are shown in Table 47-1. (WRC-07)
116 Maritime Manual
TABLE 47-1
Requirements for radio electronic and operator’s certificates
The relevant certificate is issued to a candidate who
has given proof of the technical and professional
knowledge and qualifications enumerated below, as
indicated by an asterisk in the appropriate box
1st-class
radio
electronic
certificate
2nd-class
radio
electronic
certificate
General
operator’s
certificate
Restricted
operator’s
certificate
Knowledge of the principles of electricity and the
theory of radio and of electronics sufficient to meet
the requirements specified below:
* *
Theoretical knowledge of GMDSS radiocommu-
nication equipment, including narrow-band direct-
printing telegraph and radiotelephone transmitters and
receivers, digital selective calling equipment, ship
earth stations, emergency position-indicating
radiobeacons, marine antenna systems, radio
equipment for survival craft together with all auxiliary
items, including power supplies, as well as general
knowledge of the principles of other equipment
generally used for radionavigation, with particular
reference to maintaining equipment in service.
*
General theoretical knowledge of GMDSS radio-
communication equipment, including narrow-band
direct-printing telegraph and radiotelephone
transmitters and receivers, digital selective calling
equipment, ship earth stations, emergency position-
indicating radiobeacons, marine antenna systems,
radio equipment for survival craft together with all
auxiliary items, including power supplies, as well as
general knowledge of the principles of other
equipment generally used for radionavigation, with
particular reference to maintaining equipment in
service.
*
Practical knowledge of the operation and knowledge
of the preventive maintenance of the equipment
indicated above.
* *
Practical knowledge necessary for the location and
repair (using appropriate testing equipment and tools)
of faults in the equipment mentioned above which
may occur during a voyage.
*
Practical knowledge necessary for effecting repairs in
the case of faults in the equipment indicated above,
using the means available on board and, if necessary,
replacing modular units.
*
Part B – SECTION I – RR47 117
TABLE 47-1 (end)
NOTE 1 – A restricted operator’s certificate covers only the operation of GMDSS equipment required
for GMDSS sea areas A1, and does not cover the operation of GMDSS A2/A3/A4 equipment fitted on a
ship over and above the basic A1 requirements, even if the ship is in a sea area A1. GMDSS sea
areas A1, A2, A3 and A4 are identified in the International Convention for the Safety of Life at Sea,
(SOLAS), 1974, as amended.
NOTE 2 – The conditions for the issuing of the long-range and short-range Certificates are contained in
Resolution 343 (WRC-97). (WRC-07)
The relevant certificate is issued to a candidate who
has given proof of the technical and professional
knowledge and qualifications enumerated below, as
indicated by an asterisk in the appropriate box
1st-class
radio
electronic
certificate
2nd-class
radio
electronic
certificate
General
operator’s
certificate
Restricted
operator’s
certificate
Detailed practical knowledge of the operation of all the
GMDSS sub-systems and equipment. * * *
Practical knowledge of the operation of all the GMDSS
sub-systems and equipment which is required while the
ship is within the range of VHF coast stations (see
NOTE 1).
*
Ability to send and to receive correctly by radiote-
lephone and direct-printing telegraphy. * * *
Ability to send and to receive correctly by radio-
telephone. *
Detailed knowledge of the regulations applying to
radiocommunications, knowledge of the documents
relating to charges for radiocommunications and
knowledge of those provisions of the International
Convention for the Safety of Life at Sea (SOLAS),
1974, as amended which relate to radio.
* * *
Knowledge of the regulations applying to radio-
telephone communications and specifically of that part
of those regulations relating to the safety of life.
*
Sufficient knowledge of one of the working languages
of the Union. Candidates should be able to express
themselves satisfactorily in that language, both orally
and in writing.
* * *
An elementary knowledge of one of the working
languages of the Union. Candidates should be able to
express themselves satisfactorily in that language, both
orally and in writing. Administrations may waive the
above language requirements for holders of a restricted
operator’s certificate when the ship station is confined
to a limited area specified by the administration
concerned. In such cases the certificate shall be suitably
endorsed.
*
118 Maritime Manual
ARTICLE 48
Personnel
Section I – Personnel of coast stations and coast earth stations
48.1 § 1 Administrations shall ensure that the staff on duty in coast stations
and in coast earth stations are adequately qualified to operate the stations efficiently.
Section II – Class and minimum number of personnel for ship stations
and ship earth stations
48.2 § 2 Administrations shall ensure that the personnel of ship stations and
ship earth stations are adequately qualified to enable efficient operation of the station,
and shall take steps to ensure the operational availability and maintenance of equipment
for distress and safety communications in accordance with the relevant international
agreements.
48.3 § 3 An adequately qualified person shall be available to act as a dedicated
communications operator in cases of distress.
48.4 § 4 The personnel of ship stations and ship earth stations for which a
radio installation is compulsory under international agreements and which use the
frequencies and techniques prescribed in Chapter VII shall, with respect to the
provisions of Article 47, include:
48.5 a) for stations on board ships which sail beyond the range of VHF coast
stations, taking into account the provisions of the International Convention for
the Safety of Life at Sea (SOLAS), 1974, as amended: a holder of a first- or
second-class radio electronic certificate or a general operator’s certificate;
48.6 b) for stations on board ships which sail solely within the range of VHF
coast stations, taking into account the provisions of the International
Convention for the Safety of Life at Sea (SOLAS), 1974, as amended: a holder
of a first- or second-class radio electronic certificate or a general operator’s
certificate or a restricted operator’s certificate.
Part B – SECTION I – RR48 119
48.7 § 5 The personnel of ship stations and ship earth stations for which a
radio installation is not compulsory either under international agreements or national
regulations and which use the frequencies and techniques prescribed in Chapter VII
shall be adequately qualified and certificated in accordance with the administration’s
requirements. Guidance concerning appropriate qualifications and certification is
provided in Resolution 343 (WRC-97). That Resolution describes two appropriate
certificates for use by personnel of ship stations and ship earth stations for which a
radio installation is not compulsory.
120 Maritime Manual – SECTION I – RR49
ARTICLE 49
Inspection of stations
49.1 § 1 1) The governments or appropriate administrations of countries
which a ship station or ship earth station visits may require the production of the licence
for examination. The operator of the station, or the person responsible for the station,
shall facilitate this examination. The licence shall be kept in such a way that it can be
produced upon request. As far as possible, the licence, or a copy certified by the
authority which has issued it, should be permanently exhibited in the station.
49.2 2) The inspectors shall have in their possession an identity card or
badge, issued by the competent authority, which they shall show on request of the
master or person responsible for the ship or other vessel carrying the ship station or the
ship earth station.
49.3 3) When the licence cannot be produced or when manifest
irregularities are observed, governments or administrations may inspect the radio
installations in order to satisfy themselves that these conform to the conditions imposed
by these Regulations.
49.4 4) In addition, inspectors have the right to require the production of
the operators’ certificates, but proof of professional knowledge may not be demanded.
49.5 § 2 1) When a government or an administration has found it necessary
to adopt the course indicated in No. 49.3, or when the operators’ certificates cannot be
produced, the government or administration to which the ship station or ship earth
station is subject shall be so informed without delay. In addition, the procedure
specified in Article 15 is followed when necessary.
49.6 2) Before leaving, the inspector shall report the result of his
inspection to the master, or the person responsible for the ship or other vessel carrying
the ship station or ship earth station. If any breach of the conditions imposed by these
Regulations is observed, the inspector shall make this report in writing.
49.7 § 3 Member States undertake not to impose upon foreign ship stations or
upon foreign ship earth stations, which are temporarily within their territorial waters or
which make a temporary stay in their territory, technical and operating conditions more
severe than those contemplated in these Regulations. This undertaking in no way affects
arrangements which are made under international agreements relating to maritime
navigation, and which are therefore not covered by these Regulations.
49.8 § 4 The frequencies of emissions of ship stations shall be checked by the
inspection service to which these stations are subject.
Part B – SECTION I – RR50 121
ARTICLE 50
Working hours of stations
50.1 § 1 In order to permit the application of the following rules on the subject
of hours of watch, every station of the maritime mobile service and the maritime
mobile-satellite service shall have an accurate clock correctly regulated to Coordinated
Universal Time (UTC).
50.2 § 2 Coordinated Universal Time (UTC), reckoned from 0000 to 2359 h
beginning at midnight, shall be used for all entries in the radiocommunication service
log and in all similar documents of ships compulsorily equipped with
radiocommunication apparatus in compliance with an international agreement; this
same provision will apply, as far as possible, to other ships.
50.3 § 3 1) The services of coast stations and coast earth stations are, as far
as possible, continuous (day and night). Certain coast stations, however, may have a
service of limited duration. Each administration or recognized private operating agency
duly authorized to that effect fixes the hours of service for coast stations under its
jurisdiction.
50.4 2) These hours of service shall be notified to the
Radiocommunication Bureau, who shall publish them in the List of Coast Stations and
Special Service Stations (List IV). (WRC-07)
50.5 § 4 Coast stations whose service is not continuous shall not close before
finishing all operations resulting from a distress call or from an urgency or safety
signal. (WRC-07)
122 Maritime Manual
ARTICLE 51
Conditions to be observed in the maritime services
Section I – Maritime mobile service
51.1 A – General
51.2 § 1 The energy radiated by receiving apparatus shall be reduced to the
lowest practical value and shall not cause harmful interference to other stations.
51.3 § 2 Administrations shall take all practicable steps necessary to ensure
that the operation of any electrical or electronic apparatus installed in ship stations does
not cause harmful interference to the essential radio services of stations which are
operating in accordance with the provisions of these Regulations.
51.4 § 3 1) Changes of frequency in the sending and receiving apparatus of
any ship station shall be capable of being made as rapidly as possible.
51.5 2) Installations of any ship station shall be capable, once
communication is established, of changing from transmission to reception and vice
versa in as short a time as possible.
51.5A 3) The operation of a broadcasting service (see No. 1.38) by a ship
station at sea is prohibited (see also No. 23.2).
51.6 § 4 Ship stations and ship earth stations other than survival craft stations
shall be provided with the documents enumerated in the appropriate section of
Appendix 16.
51.7 § 5 When any ship station transmitter itself cannot be controlled in such a
way that its frequency satisfies the tolerance specified in Appendix 2, the ship station
shall be provided with a device, having a precision equal to at least one-half of this
tolerance, for measuring the frequency of the emission.
Part B – SECTION I – RR51 123
51.24 C – Ship stations using digital selective calling
51.25 § 12 The characteristics of the digital selective calling equipment shall be
in accordance with ITU-R Recommendations (see Resolution 27 (Rev.WRC-03)*).
51.26 C1 – Bands between 415 kHz and 535 kHz
51.27 § 13 All ship stations equipped with apparatus for digital selective calling
to work in the authorized bands between 415 kHz and 535 kHz shall be able to send and
receive class F1B or J2B emissions on at least two digital selective calling channels
necessary for their service.
51.28 C2 – Bands between 1 606.5 kHz and 4 000 kHz (WRC-03)
51.29 § 14 All ship stations equipped with digital selective calling apparatus to
work in the authorized bands between 1 606.5 kHz and 4 000 kHz shall be able
to: (WRC-03)
51.30 a) send and receive class F1B or J2B emissions on the frequency
2 187.5 kHz;
51.31 b) in addition, send and receive class F1B or J2B emissions on other
digital selective calling frequencies in this band necessary to carry out their
service.
51.32 C3 – Bands between 4 000 kHz and 27 500 kHz
51.33 § 15 All ship stations equipped with digital selective calling apparatus to
work in the authorized bands between 4 000 kHz and 27 500 kHz shall be able to:
51.34 a) send and receive class F1B or J2B emissions on the frequencies
designated for digital selective distress calling in each of the maritime
HF bands in which they are operating (see also No. 32.9);
51.35 b) send and receive class F1B or J2B emissions on an international
calling channel (specified in Recommendation ITU-R M.541-9) in each of the
HF maritime mobile bands necessary for their service; (WRC-07)
51.36 c) send and receive class F1B or J2B emissions on other digital selective
calling channels in each of the HF maritime mobile bands necessary for their
service.
_______________
* Note by the Secretariat: This Resolution was revised by WRC-07.
124 Maritime Manual
51.37 C4 – Bands between 156 MHz and 174 MHz
51.38 § 16 All ship stations equipped with apparatus for digital selective calling
to work in the authorized bands between 156 MHz and 174 MHz shall be able to send
and receive class G2B emissions on the frequency 156.525 MHz.
51.39 CA – Ship stations using narrow-band direct-printing telegraphy
51.40 § 17 1) All ship stations using narrow-band direct-printing telegraphy
equipment shall be able to send and receive on the frequency designated for distress
traffic by narrow-band direct-printing telegraphy in the frequency bands in which they
are operating.
51.41 2) The characteristics of the narrow-band direct-printing equipment
shall be in accordance with Recommendations ITU-R M.476-5, ITU-R M.625-3 and
ITU-R M.627-1.
51.42 CA1 – Bands between 415 kHz and 535 kHz
51.43 § 18 All ship stations equipped with narrow-band direct-printing
telegraphy apparatus to work in the authorized bands between 415 kHz and 535 kHz
shall be able to:
51.44 a) send and receive class F1B or J2B emissions on the working
frequencies necessary to carry out their service;
51.45 b) receive class F1B emissions on 518 kHz, if complying with the
provisions of Chapter VII.
51.46 CA2 – Bands between 1 606.5 kHz and 4 000 kHz (WRC-03)
51.47 § 19 All ship stations equipped with narrow-band direct-printing
telegraphy apparatus to work in the authorized bands between 1 606.5 kHz and
4 000 kHz shall be able to send and receive class F1B or J2B emissions on working
frequencies necessary to carry out their service. (WRC-03)
51.48 CA3 – Bands between 4 000 kHz and 27 500 kHz
51.49 § 20 All ship stations equipped with narrow-band direct-printing
telegraphy apparatus to work in the authorized bands between 4 000 kHz and
27 500 kHz shall be able to send and receive class F1B or J2B emissions on working
frequencies in each of the HF maritime mobile bands necessary to carry out their
service.
Part B – SECTION I – RR51 125
51.50 D – Ship stations using radiotelephony
51.51 D1 – Bands between 1 606.5 kHz and 4 000 kHz (WRC-03)
51.52 § 21 All ship stations equipped with radiotelephony apparatus to work in
the authorized bands between 1 606.5 kHz and 2 850 kHz shall be able to:
51.53 a) send class J3E emissions on a carrier frequency of 2 182 kHz and
receive class J3E emissions on a carrier frequency of 2 182 kHz, except for
such apparatus as is referred to in No. 51.56; (WRC-07)
51.54 b) send, in addition, J3E emissions on at least two working frequencies1;
51.55 c) receive, in addition, J3E emissions on all other frequencies necessary
for their service.
51.56 § 22 The provisions of Nos. 51.54 and 51.55 do not apply to apparatus
provided solely for distress, urgency and safety purposes.
51.57 D2 – Bands between 4 000 kHz and 27 500 kHz
51.58 § 23 All ship stations equipped with radiotelephony to work in the
authorized bands between 4 000 kHz and 27 500 kHz and which do not comply with the
provisions of Chapter VII should be able to send and receive on the carrier frequencies
4 125 kHz and 6 215 kHz. However, all ship stations which comply with the provisions
of Chapter VII shall be able to send and receive on the carrier frequencies designated in
Article 31 for distress and safety traffic by radiotelephony for the frequency bands in
which they are operating. (WRC-07)
51.59 D3 – Bands between 156 MHz and 174 MHz
51.60 § 24 All ship stations equipped with radiotelephony to work in the
authorized bands between 156 MHz and 174 MHz (see No. 5.226 and Appendix 18)
shall be able to send and receive class G3E emissions on:
51.61 a) the distress, safety and calling frequency 156.8 MHz;
51.62 b) the primary intership frequency 156.3 MHz;
51.63 c) the intership navigation safety frequency 156.65 MHz;
51.64 d) all the frequencies necessary for their service.
_______________
1 51.54.1 In certain areas, administrations may reduce this requirement to one working
frequency.
126 Maritime Manual
Section II – Maritime mobile-satellite service
51.65 § 25 The energy radiated by receiving apparatus shall be reduced to the
lowest practical value and shall not cause harmful interference to other stations.
51.66 § 26 Administrations shall take all practicable steps necessary to ensure
that the operation of any electrical or electronic apparatus installed in ship earth stations
does not cause harmful interference to the essential radio services of stations which are
operating in accordance with the provisions of these Regulations.
Section III – Stations on board aircraft communicating with stations of
the maritime mobile service and the maritime mobile-satellite service
51.67 A – General provisions
51.68 § 27 1) Stations on board aircraft may communicate with stations of the
maritime mobile or maritime mobile-satellite services. They shall conform to those
provisions of these Regulations which relate to these services.
51.69 2) For this purpose stations on board aircraft should use the
frequencies allocated to the maritime mobile or maritime mobile-satellite services.
51.70 3) Stations on board aircraft, when handling public correspondence
with stations of the maritime mobile service or of the maritime mobile-satellite service,
shall comply with all the provisions applicable to the handling of public correspondence
in the maritime mobile or maritime mobile-satellite services (see particularly
Articles 53, 54, 55, 57 and 58).
51.71 § 28 In the case of communication between stations on board aircraft and
stations of the maritime mobile service, radiotelephone calling may be renewed as
specified in the most recent version of Recommendation ITU-R M.1171 and
radiotelegraph calling may be renewed after an interval of five minutes,
notwithstanding the procedure contained in the most recent version of Recommendation
ITU-R M.1170. (WRC-07)
Part B – SECTION I – RR51 127
51.72 B – Provisions relating to the use of frequencies between
156 MHz and 174 MHz
51.73 § 29 1) Having regard to interference which may be caused by aircraft
stations at high altitudes, frequencies in the maritime mobile bands above 30 MHz shall
not be used by aircraft stations, with the exception of those frequencies between
156 MHz and 174 MHz specified in Appendix 18 which may be used provided that the
following conditions are observed:
51.74 a) the altitude of aircraft stations shall not exceed 300 m (1 000 feet),
except for reconnaissance aircraft participating in ice-breaking operations,
where an altitude of 450 m (1 500 feet) is allowed;
51.75 b) the mean power of aircraft station transmitters shall not exceed 5 W;
however, a power of 1 W or less shall be used to the maximum extent
possible;
51.76 c) aircraft stations shall use the channels designated for this purpose in
Appendix 18;
51.77 d) except as provided in No. 51.75, aircraft station transmitters shall
comply with the technical characteristics given in Recommendation ITU-R
M.489-2;
51.78 e) the communications of an aircraft station shall be brief and limited to
operations in which stations of the maritime mobile service are primarily
involved and where direct communication between the aircraft and the ship or
coast station is required.
51.79 2) The frequency 156.3 MHz may be used by stations on board
aircraft for safety purposes. It may also be used for communication between ship
stations and stations on board aircraft engaged in coordinated search and rescue
operations (see Appendix 15). (WRC-07)
51.80 3) The frequency 156.8 MHz may be used by stations on board
aircraft for safety purposes only (see Appendix 15). (WRC-07)
128 Maritime Manual
ARTICLE 52
Special rules relating to the use of frequencies
Section I – General provisions
52.1 A – Single-sideband radiotelegraph transmissions
52.2 § 1 1) Where these provisions specify A1A emission, class A1B or J2A
emissions shall be considered equivalent.
52.3 2) Where these provisions specify class F1B emission, class J2B
and J2D emissions shall be considered equivalent. However, class J2D emission shall
not be used with the HF distress and safety frequencies listed in Appendix 15.
52.4 B – Bands between 415 kHz and 535 kHz
52.5 § 2 Ship stations authorized to work in the bands between 415 kHz and
535 kHz shall transmit on the frequencies indicated in this Article (see No. 52.39).
52.6 § 3 1) In the maritime mobile service, no assignments shall be made on
the frequency 518 kHz other than for transmission by coast stations of meteorological
and navigational warnings and urgent information to ships by means of automatic
narrow-band direct-printing telegraphy (International NAVTEX System).
52.7 2) In the maritime mobile service, the frequency 490 kHz is used
exclusively for the transmission by coast stations of meteorological and navigational
warnings and urgent information to ships by means of narrow-band direct-printing
telegraphy. (WRC-03)
52.8 C – Bands between 1 606.5 kHz and 4 000 kHz (WRC-03)
52.9 § 4 1) In Region 1, frequencies assigned to stations operating in the
bands between 1 850 kHz and 3 800 kHz (see Article 5) should, whenever possible, be
in accordance with the following subdivision:
– 1 850-1 950 kHz: Coast stations, single-sideband radiotelephony.
– 1 950-2 045 kHz: Ship stations, single-sideband radiotelephony.
– 2 194-2 262.5 kHz: Ship stations, single-sideband radiotelephony.
Part B – SECTION I – RR52 129
– 2 262.5-2 498 kHz: Intership, single-sideband radiotelephony.
– 2 502-2 578 kHz: Ship stations, narrow-band direct-printing
telegraphy.
– 2 578-2 850 kHz: Coast stations, narrow-band direct-printing
telegraphy and single-sideband radiotelephony.
– 3 155-3 200 kHz: Ship stations, narrow-band direct-printing
telegraphy.
– 3 200-3 340 kHz: Ship stations, single-sideband radiotelephony.
– 3 340-3 400 kHz: Intership, single-sideband radiotelephony.
– 3 500-3 600 kHz: Intership, single-sideband radiotelephony.
– 3 600-3 800 kHz: Coast stations, single-sideband radiotelephony.
52.10 2) In Region 1, frequencies assigned to stations operating in the
bands listed below shall be in accordance with the following subdivision:
– 1 606.5-1 625 kHz: Coast stations, narrow-band direct-printing
telegraphy, digital selective calling.
– 1 635-1 800 kHz: Coast stations, single-sideband radiotelephony.
– 2 045-2 141.5 kHz: Ship stations, single-sideband radiotelephony.
– 2 141.5-2 160 kHz: Ship stations, narrow-band direct-printing
telegraphy, digital selective calling.
52.11 § 5 In Regions 2 and 3, the carrier frequencies 2 635 kHz (assigned
frequency 2 636.4 kHz) and 2 638 kHz (assigned frequency 2 639.4 kHz) are used as
single-sideband intership radiotelephony working frequencies in addition to the
frequencies prescribed for common use in certain services. The carrier frequencies
2 635 kHz and 2 638 kHz should be used with class J3E emissions only. In Region 3
these frequencies are protected by a guardband between 2 634 kHz and 2 642 kHz.
52.12 D – Bands between 4 000 kHz and 27 500 kHz
52.13 § 6 Bands exclusively allocated to the maritime mobile service between
4 000 kHz and 27 500 kHz (see Article 5) are subdivided into categories and sub-bands
as indicated in Appendix 17.
52.14 E – Bands between 156 MHz and 174 MHz
52.15 § 7 The ship movement service should be operated only on frequencies
allocated to the maritime mobile service in the band 156-174 MHz.
130 Maritime Manual
Section III – Use of frequencies for narrow-band direct-printing telegraphy
52.94 A – General
52.95 § 44 Frequencies assigned to coast stations for narrow-band direct-printing
telegraphy shall be indicated in the List of Coast Stations and Special Service Stations
(List IV). This List shall also indicate any other useful information concerning the
service performed by each coast station. (WRC-07)
52.96 B – Bands between 415 kHz and 535 kHz
52.97 § 45 All ship stations equipped with narrow-band direct-printing apparatus
to work in the authorized bands between 415 kHz and 535 kHz shall be able to send and
receive class F1B emissions as specified in No. 51.44. Additionally, ship stations
complying with the provisions of Chapter VII shall be able to receive class F1B
emissions on 518 kHz (see No. 51.45).
52.99 C – Bands between 1 606.5 kHz and 4 000 kHz (WRC-03)
52.100 § 46 1) All ship stations equipped with narrow-band direct-printing
telegraph apparatus to work in the authorized bands between 1 606.5 kHz and
4 000 kHz shall be able to send and receive class F1B or J2B emissions on at least two
working frequencies. (WRC-03)
52.101 2) Narrow-band direct-printing telegraphy is forbidden in the band
2 170-2 194 kHz, except as provided for in Appendix 15 and Resolution 354
(WRC-07). (WRC-07)
52.102 D – Bands between 4 000 kHz and 27 500 kHz
52.103 § 47 All ship stations equipped with narrow-band direct-printing telegraph
apparatus to work in the authorized bands between 4 000 kHz and 27 500 kHz shall be
able to send and receive class F1B emissions as specified in No. 51.49. The assignable
frequencies are indicated in Appendix 17.
Part B – SECTION I – RR52 131
52.104 § 48 Coast stations employing class F1B emissions and operating in the
bands exclusively allocated to the maritime mobile service between 4 000 kHz and
27 500 kHz shall at no time use mean powers in excess of the following:
52.105 1) In all bands, the working frequencies for ship stations using
narrow-band direct-printing telegraphy at speeds not exceeding 100 Bd for FSK and
200 Bd for PSK, including those paired with the working frequencies assignable to
coast stations (see Appendix 17), are spaced 0.5 kHz apart. The frequencies assignable
to ship stations which are paired with those used by coast stations are shown in
Appendix 17. The frequencies assignable to ship stations which are not paired with
those used by coast stations are shown in Appendix 17.
52.107 2) Each administration shall, if necessary, assign to each ship
station under its jurisdiction and employing non-paired narrow-band direct-printing
telegraphy one or more frequencies reserved for this purpose and shown in
Appendix 17.
52.108 E – Bands between 156 MHz and 174 MHz
52.109 § 49 All ship stations equipped with direct-printing telegraph apparatus
may work in the authorized bands between 156 MHz and 174 MHz and shall conform
to the provisions of Appendix 18.
Section IV – Use of frequencies for digital selective-calling
52.110 A – General
52.111 § 50 The provisions described in this Section are applicable to calling and
acknowledgement, when digital selective-calling techniques are used, except in cases of
distress, urgency and safety, to which the provisions of Chapter VII apply.
Band Maximum
mean power
4 MHz 5 kW
6 MHz 5 kW
8 MHz 10 kW
12 MHz 15 kW
16 MHz 15 kW
18/19 MHz 15 kW
22 MHz 15 kW
25/26 MHz 15 kW
132 Maritime Manual
52.112 § 51 The characteristics of the digital selective-calling equipment shall be
in accordance with Recommendation ITU-R M.541-9 and should be in accordance with
the most recent version of Recommendation ITU-R M.493. (WRC-07)
52.113 § 52 The frequencies on which coast stations provide services using digital
selective-calling techniques shall be indicated in the List of Coast Stations and Special
Service Stations (List IV), which shall also supply any other useful information
concerning such services. (WRC-07)
52.114 B – Bands between 415 kHz and 526.5 kHz
B1 – Mode of operation
52.115 § 53 1) The class of emission to be used for digital selective-calling and
acknowledgement in the authorized bands between 415 kHz and 526.5 kHz shall be
F1B.
52.116 2) When transmitting digital selective calls and acknowledgements
in the bands between 415 kHz and 526.5 kHz, coast stations should use the minimum
power necessary to cover their service area.
52.117 § 54 Transmissions of digital selective calls and acknowledgements by
ship stations shall be limited to a mean power of 400 W.
B2 – Call and acknowledgement
52.118 § 55 For call and acknowledgement by digital selective-calling techniques,
an appropriate channel shall be used.
52.119 § 56 The international digital selective-calling frequency 455.5 kHz may
be assigned to any coast station. In order to reduce interference on this frequency, it
may be used as a general rule by coast stations to call ships of another nationality, or in
cases where it is not known on which digital selective-calling frequencies within these
bands the ship station is maintaining watch.
52.120 § 57 The international digital selective-calling frequency 458.5 kHz may
be used by any ship station. In order to reduce interference on this frequency, it shall
only be used when calling cannot be made on national frequencies assigned to the coast
station.
52.121 § 58 The frequency to be used for transmission of an acknowledgement
shall normally be the frequency paired with the calling frequency used.
Part B – SECTION I – RR52 133
B3 – Watch
52.122 § 59 1) A coast station providing international public correspondence
service using digital selective-calling techniques within the bands between 415 kHz and
526.5 kHz should, during its hours of service, maintain automatic digital selective-
calling watch on appropriate national or international calling frequencies. The hours
and frequencies shall be indicated in the List of Coast Stations and Special Service
Stations (List IV). (WRC-07)
52.123 2) Ship stations equipped with apparatus for digital selective-calling
to work in the authorized bands between 415 kHz and 526.5 kHz should, when within
the coverage area of coast stations providing services using digital selective-calling
techniques in these bands, maintain an automatic digital selective-calling watch on one
or more appropriate digital selective-calling frequencies within these bands, taking into
account the digital selective-calling frequencies operated by the coast stations.
52.124 C – Bands between 1 606.5 kHz and 4 000 kHz (WRC-03)
C1 – Mode of operation
52.125 § 60 1) The class of emission to be used for digital selective-calling and
acknowledgement in the bands between 1 606.5 kHz and 4 000 kHz shall be
F1B. (WRC-03)
52.126 2) Coast stations should, when transmitting digital selective calls
and acknowledgements in the bands between 1 606.5 kHz and 4 000 kHz, use the
minimum power necessary to cover their service area. (WRC-03)
52.127 3) In Region 1, transmissions of digital selective calls and
acknowledgements by ship stations shall be limited to a mean power of 400 W.
C2 – Call and acknowledgement
52.128 § 61 1) When calling a coast station by digital selective-calling
techniques, ship stations should use for the call, in order of preference:
52.129 a) a national digital selective-calling channel on which the coast station
is maintaining watch;
52.130 b) subject to the provisions of No. 52.131, the international digital
selective-calling frequency 2 189.5 kHz.
52.131 2) The international digital selective-calling frequency 2 189.5 kHz
may be assigned to any ship station. In order to reduce interference on this frequency, it
may be used as a general rule by ship stations to call coast stations of another
nationality.
134 Maritime Manual
52.132 3) A ship station calling another ship station by digital selective-
calling techniques should use the frequency 2 177 kHz for the call. Acknowledgements
of such calls should also be made on this frequency.
52.133 § 62 1) When calling ship stations by digital selective-calling techniques,
coast stations should use for the call, in the order of preference:
52.134 a) a national digital selective-calling channel on which the coast station
is maintaining watch;
52.135 b) subject to the provisions of No. 52.136, the international digital
selective-calling frequency 2 177 kHz.
52.136 2) The international digital selective-calling frequency 2 177 kHz
may be assigned to any coast station. In order to reduce interference on this frequency,
it may be used as a general rule by coast stations to call ships of another nationality, or
in cases where it is not known on which digital selective-calling frequencies within the
bands between 1 606.5 kHz and 4 000 kHz the ship station is maintaining
watch. (WRC-03)
52.137 § 63 The frequency to be used for transmission of an acknowledgement
shall normally be the frequency paired with the frequency used for the call received, as
indicated in the List of Coast Stations and Special Service Stations (List IV) (see also
No. 52.113). (WRC-07)
C3 – Watch
52.138 § 64 1) The provisions detailed in this Sub-section are applicable to
watch-keeping by digital selective-calling, except for distress, urgency and safety
purposes, to which the provisions of Section III of Article 31 apply.
52.139 2) A coast station providing international public correspondence
service using digital selective-calling techniques within the bands between 1 606.5 kHz
and 4 000 kHz should, during its hours of service, maintain automatic digital selective-
calling watch on appropriate national or international calling frequencies. The hours
and frequencies shall be indicated in the List of Coast Stations and Special Service
Stations (List IV). (WRC-07)
52.140 3) Ship stations equipped with apparatus for digital selective-calling
to work in the authorized bands between 1 606.5 kHz and 4 000 kHz should, when
within the coverage area of coast stations providing services using digital selective-
calling techniques in these bands, maintain an automatic digital selective-calling watch
on one or more appropriate digital selective-calling frequencies within these bands,
taking into account the digital selective-calling frequencies operated by the coast
stations. (WRC-03)
Part B – SECTION I – RR52 135
52.141 D – Bands between 4 000 kHz and 27 500 kHz
D1 – Mode of operation
52.142 § 65 1) The class of emission to be used for digital selective-calling and
acknowledgement in the authorized bands between 4 000 kHz and 27 500 kHz shall be
F1B.
52.143 2) When transmitting digital selective calls and acknowledgements
in the bands between 4 000 kHz and 27 500 kHz, coast stations shall at no time use a
mean power in excess of the following values:
52.144 3) Transmissions of digital selective calls and acknowledgements
by ship stations in the bands between 4 000 kHz and 27 500 kHz shall be limited to a
mean power of 1.5 kW.
D2 – Call and acknowledgement
52.145 § 66 A station calling another station by digital selective-calling
techniques within the authorized bands between 4 000 kHz and 27 500 kHz should
choose an appropriate digital selective-calling frequency, taking into account
propagation characteristics.
52.146 § 67 1) When calling a coast station by digital selective-calling
techniques on frequencies within the authorized bands between 4 000 kHz and
27 500 kHz, ship stations should use for the call, in order of preference:
52.147 a) a national digital selective-calling channel on which the coast station
is maintaining watch;
Band Maximum
mean power
4 MHz 5 kW
6 MHz 5 kW
8 MHz 10 kW
12 MHz 15 kW
16 MHz 15 kW
18/19 MHz 15 kW
22 MHz 15 kW
25/26 MHz 15 kW
136 Maritime Manual
52.148 b) subject to the provisions of No. 52.149, one of the international
digital selective-calling frequencies. (WRC-07)
52.149 2) The international digital selective-calling frequencies shall be as
indicated in Recommendation ITU-R M.541-9 and may be used by any ship station. In
order to reduce interference on these frequencies, they shall only be used when calling
cannot be made on nationally assigned frequencies. (WRC-07)
52.150 § 68 1) When calling ship stations by digital selective-calling techniques
on frequencies within the bands between 4 000 kHz and 27 500 kHz coast stations
should use for the call, in order of preference:
52.151 a) a national digital selective-calling channel on which the coast station
is maintaining watch;
52.152 b) subject to the provisions of No. 52.153, one of the international
digital selective-calling frequencies. (WRC-07)
52.153 2) The international digital selective-calling frequencies shall be as
indicated in Recommendation ITU-R M.541-9 and may be assigned to any coast
station. In order to reduce interference on these frequencies, they may be used as a
general rule by coast stations to call ships of another nationality, or in cases where it is
not known on which digital selective-calling frequencies within the bands concerned
the ship station is maintaining watch. (WRC-07)
D3 – Watch
52.154 § 69 1) The provisions detailed in this Sub-section are applicable to
watch-keeping by digital selective-calling, except for distress, urgency and safety
purposes, to which the provisions of Section III of Article 31 apply.
52.155 2) A coast station providing international public correspondence
service using digital selective-calling techniques within the bands between 4 000 kHz
and 27 500 kHz should, during its hours of service, maintain automatic digital selective-
calling watch on the appropriate digital selective-calling frequencies as indicated in the
List of Coast Stations and Special Service Stations (List IV). (WRC-07)
52.156 3) Ship stations equipped with apparatus for digital selective-calling
to work in the authorized bands between 4 000 kHz and 27 500 kHz should maintain
automatic digital selective-calling watch on appropriate digital selective-calling
frequencies within these bands, taking into account propagation characteristics and the
calling frequencies for coast stations providing service using digital selective-calling
techniques.
Part B – SECTION I – RR52 137
52.157 E – Bands between 156 MHz and 174 MHz
E1 – Mode of operation
52.158 § 70 The class of emission to be used for digital selective-calling and
acknowledgement in the authorized bands between 156 MHz and 174 MHz shall be
G2B.
E2 – Call and acknowledgement
52.159 § 71 1) The frequency 156.525 MHz is an international frequency in the
maritime mobile service used for distress, urgency, safety and calling by digital
selective-calling techniques (see Nos. 33.8 and 33.31 and Appendix 15). (WRC-07)
52.160 2) Calling by digital selective-calling techniques within the
authorized bands between 156 MHz and 174 MHz, from ship to coast station, from
coast station to ship and from ship to ship should, as a general rule, be made on the
digital selective-calling frequency 156.525 MHz.
E3 – Watch
52.161 § 72 Information concerning watch-keeping by automatic digital selective-
calling on the frequency 156.525 MHz by coast stations shall be given in the List of
Coast Stations and Special Service Stations (List IV) (see also No. 31.13). (WRC-07)
52.162 § 73 Ship stations equipped with apparatus for digital selective-calling to
work in the authorized bands between 156 MHz and 174 MHz should, while at sea,
maintain an automatic digital selective-calling watch on the frequency 156.525 MHz
(see also No. 31.17).
Section V – Use of frequencies for wide-band telegraphy, facsimile, special
transmission systems and oceanographic data transmissions
52.163 A – Wide-band telegraphy, facsimile and special transmission systems
52.164 A1 – Bands between 1 606.5 kHz and 4 000 kHz (WRC-03)
52.165 § 74 In Region 2, the frequencies in the band 2 068.5-2 078.5 kHz are
assigned to ship stations using wide-band telegraphy, facsimile and special transmission
systems. The provisions of No. 52.171 apply.
138 Maritime Manual
52.166 A2 – Bands between 4 000 kHz and 27 500 kHz
52.167 § 75 In all bands, the working frequencies for ship stations equipped to use
wide-band telegraphy, facsimile and special transmission systems are spaced 4 kHz
apart. The assignable frequencies are shown in Appendix 17.
52.168 § 76 1) Each administration shall assign to each ship station under its
jurisdiction and employing wide-band telegraphy, facsimile and special transmission
systems one or more series of the working frequencies reserved for this purpose shown
in Appendix 17. The total number of series assigned to each ship station shall be
determined by traffic requirements.
52.169 2) When ship stations employing wide-band telegraphy, facsimile
and special transmission systems are assigned less than the total number of working
frequencies in a band, the administration concerned shall assign working frequencies to
such ships in accordance with an orderly system of rotation that will ensure
approximately the same number of assignments on any one working frequency.
52.170 3) However, within the limits of the bands given in Appendix 17,
administrations may, to meet the needs of specific systems, assign frequencies in a
different manner from that shown in Appendix 17. Nevertheless administrations shall
take into account, as far as possible, the provisions of Appendix 17, concerning
channelling and the 4 kHz spacing.
52.171 § 77 Ship stations equipped for wide-band telegraphy, facsimile and
special transmission systems may, in the frequency bands reserved for such use, employ
any class of emission provided that such emissions can be contained within the wide-
band channels indicated in Appendix 17. However, the use of A1A Morse telegraphy
and telephony is excluded except for circuit alignment purposes.
52.172 § 78 Coast radiotelegraph stations employing multichannel telegraph
emissions and operating in the bands allocated exclusively to the maritime mobile
service between 4 000 kHz and 27 500 kHz shall at no time use a mean power in excess
of 2.5 kW per 500 Hz bandwidth.
52.173 B – Oceanographic data transmission systems
52.174 § 79 In all bands, the assignable frequencies for oceanographic data
transmissions are spaced 0.3 kHz apart. The assignable frequencies are shown in
Appendix 17.
52.175 § 80 The frequency bands for oceanographic data transmission systems
(see Appendix 17) may also be used by buoy stations for oceanographic data
transmission and by stations interrogating these buoys.
Part B – SECTION I – RR52 139
Section VI – Use of frequencies for radiotelephony
52.176 A – General
52.177 § 81 Except with regard to the provisions of Article 11 concerning
notification and recording of frequencies, when designating frequencies for single-
sideband radiotelephony the carrier frequency is always to be designated. The assigned
frequency shall be 1 400 Hz higher than the carrier frequency.
52.178 § 82 Coast stations shall not occupy idle radiotelephone channels by
emitting identification signals, such as those generated by call slips or tapes.
Exceptionally, a coast station, when requested by a ship station for the purpose of
establishing a radiotelephone call, may emit a receiver tuning signal of not more than
10 s duration.
52.179 § 83 However, coast stations in automatic service in the UHF band may
emit marking signals. The emission power of the signals shall however be limited to the
minimum value necessary for effective operation of the signalling. Such emissions shall
not cause harmful interference to the maritime mobile service in other countries.
52.180 § 84 The frequencies of transmission (and reception when these
frequencies are in pairs as in the case of duplex radiotelephony) assigned to each coast
station shall be indicated in the List of Coast Stations and Special Service Stations
(List IV). This List shall also indicate any other useful information concerning the
service performed by each coast station. (WRC-07)
52.181 § 85 Single-sideband apparatus in radiotelephone stations of the maritime
mobile service operating in the bands allocated to this service between 1 606.5 kHz and
4 000 kHz and in the bands allocated exclusively to this service between 4 000 kHz and
27 500 kHz shall satisfy the technical and operational conditions specified in
Recommendation ITU-R M.1173. (WRC-03)
52.182 B – Bands between 1 606.5 kHz and 4 000 kHz (WRC-03)
B1 – Mode of operation of stations
52.183 § 86 1) Unless otherwise specified in the Radio Regulations (see
Nos. 51.53, 52.188, 52.189 and 52.199), the class of emission to be used in the bands
between 1 606.5 kHz and 4 000 kHz shall be J3E. (WRC-07)
52.184 2) The peak envelope power of coast radiotelephone stations
operating in the authorized bands allocated between 1 606.5 kHz and 4 000 kHz shall
not exceed: (WRC-03)
52.185 – 5 kW for coast stations located north of latitude 32° N;
140 Maritime Manual
52.186 – 10 kW for coast stations located south of latitude 32° N.
52.187 3) The normal mode of operation for each coast station shall be
indicated in the List of Coast Stations and Special Service Stations (List IV). (WRC-07)
52.188 4) Transmissions in the bands 2 170-2 173.5 kHz and 2 190.5-
2 194 kHz with the carrier frequency 2 170.5 kHz and the carrier frequency 2 191 kHz,
respectively, are limited to class J3E emissions and are limited to a peak envelope
power of 400 W. (WRC-07)
B2 – Call and reply
52.189 § 87 1) The frequency 2 182 kHz1 is an international distress frequency
for radiotelephony (see Appendix 15 and Resolution 354 (WRC-07)). (WRC-07)
52.190 2) The frequency 2 182 kHz may also be used:
52.191 a) for call and reply in accordance with the provisions of Article 57;
52.192 b) by coast stations to announce the transmission, on another frequency,
of traffic lists as specified in Recommendation ITU-R M.1171. (WRC-03)
52.193 3) In addition, an administration may assign to its stations other
frequencies for call and reply.
52.194 § 88 To facilitate use of the frequency 2 182 kHz for distress purposes, all
transmissions on 2 182 kHz shall be kept to a minimum.
52.195 § 89 1) Before transmitting on the carrier frequency 2 182 kHz, a station
shall, in accordance with Recommendation ITU-R M.1171, listen on this frequency for
a reasonable period to make sure that no distress traffic is being sent. (WRC-03)
52.196 2) The provisions of No. 52.195 do not apply to stations in distress.
B3 – Traffic
52.197 § 90 1) Coast stations which use 2 182 kHz for calling shall be able to
use at least one other frequency in the authorized bands between 1 606.5 kHz and
2 850 kHz. (WRC-03)
_______________
1 52.189.1 Where administrations provide at their coast stations a watch on 2 182 kHz for
receiving class J3E emissions as well as class A3E and H3E emissions, ship stations may call
those coast stations for safety purposes using class H3E or J3E emissions.
Part B – SECTION I – RR52 141
52.198 2) Coast stations authorized to use radiotelephony on one or more
frequencies other than 2 182 kHz in the authorized bands between 1 606.5 kHz and
2 850 kHz shall use class J3E emissions on those frequencies (see also
No. 52.188). (WRC-03)
52.199 3) Coast stations open to the public correspondence service on one
or more frequencies between 1 606.5 kHz and 2 850 kHz shall also be capable of
transmitting class H3E and J3E emissions with a carrier frequency of 2 182 kHz, and of
receiving class A3E, H3E and J3E emissions with a carrier frequency of
2 182 kHz. (WRC-03)
52.200 4) One of the frequencies which coast stations are required to be
able to use (see No. 52.197) is printed in heavy type in the List of Coast Stations and
Special Service Stations (List IV) to indicate that it is the normal working frequency of
the stations. Supplementary frequencies, if assigned, are shown in ordinary
type. (WRC-07)
52.201 5) Working frequencies of coast stations shall be chosen in such a
manner as to avoid interference with other stations.
B4 – Additional provisions applying to Region 1
52.202 § 91 The peak envelope power of ship radiotelephone stations operating in
the authorized bands between 1 606.5 kHz and 2 850 kHz shall not exceed
400 W. (WRC-03)
52.203 § 92 1) All stations on ships making international voyages should be able
to use:
52.204 a) the following ship-to-shore working frequency, if required by their
service:
52.205 – carrier frequency 2 045 kHz (assigned frequency 2 046.4 kHz) for
class J3E emissions;
52.206 b) the following intership frequency, if required by their service:
52.207 – carrier frequency 2 048 kHz (assigned frequency 2 049.4 kHz) for
class J3E emissions;
52.208 This frequency may be used as an additional ship-to-shore frequency.
52.210 § 93 1) Ships frequently exchanging correspondence with a coast station
of a nationality other than their own may use the same frequencies as ships of the
nationality of the coast station:
52.211 – where mutually agreed by the administrations concerned; or
142 Maritime Manual
52.212 – where the facility is open to ships of all nationalities by virtue of a
note against each of the frequencies concerned in the List of Coast
Stations and Special Service Stations (List IV). (WRC-07)
52.213 2) In exceptional circumstances, if frequency usage according to
Nos. 52.203 to 52.208 or No. 52.210 is not possible, a ship station may use one of its
own assigned national ship-to-shore frequencies for communication with a coast station
of another nationality, under the express condition that the coast station as well as the
ship station shall take precautions, in accordance with Recommendation ITU-R
M.1171, to ensure that the use of such a frequency will not cause harmful interference
to the service for which the frequency in question is authorized. (WRC-03)
52.214 § 94 The following ship-to-shore frequencies:
– carrier frequency 2 051 kHz (assigned frequency 2 052.4 kHz),
– carrier frequency 2 054 kHz (assigned frequency 2 055.4 kHz), and
– carrier frequency 2 057 kHz (assigned frequency 2 058.4 kHz),
may be assigned to coast stations as receiving frequencies.
B5 – Additional provisions applying to Regions 2 and 3
52.215 § 95 All stations on ships making international voyages should, if required
by their service, be able to use the intership carrier frequencies:
2 635 kHz (assigned frequency 2 636.4 kHz)
2 638 kHz (assigned frequency 2 639.4 kHz).
The conditions of use of these frequencies are specified in No. 52.11.
52.216 C – Bands between 4 000 kHz and 27 500 kHz
C1 – Mode of operation of stations
52.217 § 96 1) The class of emission to be used for analogue radiotelephony in
the bands between 4 000 kHz and 26 175 kHz shall be J3E; for digital
telecommunications in those bands, the class of emission shall be J2D. (WRC-03)
52.218 2) The normal mode of operation of each coast station is indicated
in the List of Coast Stations and Special Service Stations (List IV). (WRC-07)
52.219 3) Coast stations employing class J3E or J2D emissions in
accordance with No. 52.217 in the bands between 4 000 kHz and 27 500 kHz shall use
the minimum power necessary to cover their service area and shall at no time use a
peak envelope power in excess of 10 kW per channel.
Part B – SECTION I – RR52 143
52.220 4) Ship stations employing class J3E or J2D emissions in
accordance with No. 52.217 in the bands between 4 000 kHz and 27 500 kHz shall at no
time use a peak envelope power in excess of 1.5 kW per channel.
C2 – Call and reply
52.220A 5) Administrations should encourage the coast stations and ship
stations under their jurisdiction to use digital selective calling techniques for call and
reply. (WRC-2000)
52.220B § 96 A When calling by radiotelephony is necessary, it should be done (in
order of preference): (WRC-2000)
52.220C 1) on the working frequencies assigned to the coast stations;
or (WRC-2000)
52.220D 2) when this is not possible, on the calling frequencies listed under
No. 52.221 or 52.221A below. (WRC-2000)
52.221 § 97 1) Ship stations may use the following carrier frequencies for
calling in radiotelephony:
4 125 kHz2, 3, 4
6 215 kHz3, 4
8 255 kHz
12 290 kHz4 (see also No. 52.221A)
16 420 kHz4 (see also No. 52.221A)
18 795 kHz
22 060 kHz
25 097 kHz (WRC-2000)
_______________
2 52.221.1 In the United States, the carrier frequency 4 125 kHz is also authorized for
common use by coast and ship stations for single-sideband radiotelephony on a simplex basis,
provided the peak envelope power of such stations does not exceed 1 kW (see also
No. 52.222.2).
3 52.221.2 The carrier frequencies 4 125 kHz and 6 215 kHz are also authorized for common
use by coast and ship stations for single-sideband radiotelephony on a simplex basis for call and
reply purposes, provided that the peak envelope power of such stations does not exceed 1 kW.
The use of these frequencies for working purposes is not permitted (see also
No. 52.221.1). (WRC-07)
4 52.221.3 The carrier frequencies 4 125 kHz, 6 215 kHz, 8 291 kHz, 12 290 kHz and
16 420 kHz are also authorized for common use by coast and ship stations for single-sideband
radiotelephony on a simplex basis for distress and safety traffic.
144 Maritime Manual
52.221A 2) Calling on the carrier frequencies 12 290 kHz and 16 420 kHz
shall be permitted only to and from rescue coordination centres (see No. 30.6.1), subject
to the safeguards of Resolution 352 (WRC-03). The alternative carrier frequencies
12 359 kHz and 16 537 kHz may be used by ship stations and coast stations for calling
on a simplex basis, provided that the peak envelope power does not exceed
1 kW. (WRC-03)
52.222 3) Coast stations may use the following carrier frequencies for
calling in radiotelephony:
4 417 kHz5
6 516 kHz5
8 779 kHz
13 137 kHz (see No. 52.222A)
17 302 kHz (see No. 52.222A)
19 770 kHz
22 756 kHz
26 172 kHz (WRC-2000)
52.222A 4) The carrier frequencies 13 137 kHz and 17 302 kHz shall not be
used as calling frequencies after 31 December 2003. The alternative carrier frequencies
12 359 kHz and 16 537 kHz may be used by ship stations and coast stations for calling
on a simplex basis, provided that the peak envelope power does not exceed
1 kW. (WRC-2000)
52.223 § 98 The hours of service of coast stations open to public correspondence
and the frequency or frequencies on which watch is maintained shall be indicated in the
List of Coast Stations and Special Service Stations (List IV). (WRC-07)
52.224 § 99 1) Before transmitting on the carrier frequencies 4 125 kHz,
6 215 kHz, 8 291 kHz, 12 290 kHz or 16 420 kHz a station shall, in accordance with
Recommendation ITU-R M.1171, listen on the frequency for a reasonable period to
make sure that no distress traffic is being sent (see No. 52.221A). (WRC-03)
52.225 2) The provisions of No. 52.224 do not apply to stations in distress.
_______________
5 52.222.2 The carrier frequencies 4 417 kHz and 6 516 kHz are also authorized for common
use by coast and ship stations for single-sideband radiotelephony on a simplex basis, provided
that the peak envelope power of such stations does not exceed 1 kW. The use of 6 516 kHz for
this purpose should be limited to daytime operation (see also No. 52.221.1).
Part B – SECTION I – RR52 145
C3 – Traffic
52.226 § 100 1) For the conduct of duplex telephony, the transmitting frequencies
of the coast stations and of the corresponding ship stations shall be associated in pairs,
as indicated in Appendix 17, except temporarily in cases where working conditions
prohibit the use of paired frequencies in order to meet operational needs.
52.227 2) The frequencies to be used for the conduct of simplex
radiotelephony are shown in Appendix 17, Section B. In these cases, the peak envelope
power of the coast station transmitter shall not exceed 1 kW.
52.228 3) The frequencies indicated in Appendix 17 for ship station
transmissions may be used by ships of any category according to traffic requirements.
52.229 4) Transmitters used for radiotelephony in the bands between
4 000 kHz and 27 500 kHz shall comply with technical characteristics specified in
Recommendation ITU-R M.1173. (WRC-03)
52.230 D – Bands between 156 MHz and 174 MHz
D1 – Call and reply
52.231 § 101 1) The frequency 156.8 MHz is the international frequency for
distress traffic and for calling by radiotelephony when using frequencies in the
authorized bands between 156 MHz and 174 MHz. The class of emission to be used for
radiotelephony on the frequency 156.8 MHz shall be G3E (as specified in
Recommendation ITU-R M.489-2). (WRC-07)
52.232 2) The frequency 156.8 MHz may also be used:
52.233 a) by coast and ship stations for call and reply in accordance with the
provisions of Articles 54 and 57;
52.234 b) by coast stations to announce the transmission on another frequency
of traffic lists, in accordance with Recommendation ITU-R M.1171, and
important maritime information. (WRC-03)
52.236 3) Any one of the channels designated in Appendix 18 for public
correspondence may be used as a calling channel if an administration so desires. Such
use shall be indicated in the List of Coast Stations and Special Service Stations
(List IV). (WRC-07)
146 Maritime Manual
52.237 5) Ship and coast stations in the public correspondence service may
use a working frequency, for calling purposes, as provided in Articles 54 and 57.
52.238 6) All emissions in the band 156.7625-156.8375 MHz capable of
causing harmful interference to the authorized transmissions of stations of the maritime
mobile service on 156.8 MHz are forbidden.
52.239 7) To facilitate the reception of distress calls and distress traffic, all
transmissions on 156.8 MHz shall be kept to a minimum and shall not exceed one
minute.
52.240 8) Before transmitting on the frequency 156.8 MHz, a station shall,
in accordance with Recommendation ITU-R M.1171, listen on this frequency for a
reasonable period to make sure that no distress traffic is being sent. (WRC-03)
52.241 9) The provisions of No. 52.240 do not apply to stations in distress.
52.241A 10) The frequency 156.525 MHz is the international distress, safety
and calling frequency for the maritime mobile VHF radiotelephone service using digital
selective calling (DSC) when using frequencies in the authorized bands between
156 MHz and 174 MHz. (WRC-07)
52.241B 11) All emissions in the band 156.4875-156.5625 MHz capable of
causing harmful interference to the authorized transmissions of stations of the maritime
mobile service on 156.525 MHz are forbidden. (WRC-07)
52.241C 12) To facilitate the reception of distress calls and distress traffic, all
transmissions on 156.525 MHz shall be kept to a minimum. (WRC-07)
D2 – Watch
52.242 § 102 1) A coast station open to the international public correspondence
service should, during its hours of service, maintain watch on its receiving frequency or
frequencies indicated in the List of Coast Stations and Special Service
Stations. (WRC-07)
52.243 2) The method of watch on a working frequency shall be no less
efficient than watch by an operator.
52.244 3) Ship stations should, where practicable, maintain watch on
156.8 MHz when within the service area of a coast station providing international
maritime mobile radiotelephone service in the band 156-174 MHz. Ship stations fitted
only with VHF radiotelephone equipment operating in the authorized bands between
156 MHz and 174 MHz should maintain watch on 156.8 MHz when at sea.
Part B – SECTION I – RR52 147
52.245 4) Ship stations, when in communication with a port station, may,
on an exceptional basis and subject to the agreement of the administration concerned,
continue to maintain watch on the appropriate port operations frequency only, provided
that watch on 156.8 MHz is being maintained by the port station.
52.246 5) Ship stations, when in communication with a coast station in the
ship movement service and subject to the agreement of the administration concerned,
may continue to maintain watch on the appropriate ship movement service frequency
only, provided that watch on 156.8 MHz is being maintained by that coast station.
52.247 § 103 A coast station in the port operations service in an area where
156.8 MHz is being used for distress, urgency or safety shall, during its working hours,
keep an additional watch on 156.6 MHz or another port operations frequency indicated
in heavy type in the List of Coast Stations and Special Service Stations
(List IV). (WRC-07)
52.248 § 104 A coast station in the ship movement service in an area where
156.8 MHz is being used for distress, urgency and safety shall, during its working
hours, keep an additional watch on the ship movement frequencies indicated in heavy
type in the List of Coast Stations and Special Service Stations (List IV). (WRC-07)
D3 – Traffic
52.249 § 105 1) Where practicable, coast stations open to the international public
correspondence service shall be capable of working with ship stations equipped for
duplex or semi-duplex operation.
52.250 2) The method of working (single-frequency or two-frequency)
specified in Appendix 18 for each channel should be used in the international services.
52.251 § 106 Communications in the port operations service shall be restricted to
those relating to operational handling, the movement and the safety of ships and, in
emergency, to the safety of persons. Messages of a public correspondence nature shall
be excluded from this service.
52.252 § 107 Communications in the ship movement service shall be restricted to
those relating to the movement of ships. Messages of a public correspondence nature
shall be excluded from this service.
52.253 § 108 1) Coast stations which use 156.8 MHz for calling shall be able to
use at least one other authorized channel in the international maritime mobile
radiotelephone service in the band 156-174 MHz.
148 Maritime Manual
52.254 2) In the band 156-174 MHz administrations shall, where
practicable, assign frequencies to coast and ship stations in accordance with the Table
of transmitting frequencies given in Appendix 18 for such international services as
administrations consider necessary.
52.256 3) In assigning frequencies to their coast stations, administrations
should collaborate in cases where harmful interference might occur.
52.257 4) Channels are designated by numbers in the Table of transmitting
frequencies given in Appendix 18.
52.258 § 109 1) In assigning frequencies to stations of authorized services, other
than maritime mobile, administrations shall avoid the possibility of interference to
international maritime services in the bands between 156 MHz and 174 MHz.
52.259 2) The use of channels for maritime mobile purposes other than
those indicated in the Table of transmitting frequencies given in Appendix 18 shall not
cause harmful interference to services which operate in accordance with that table and
shall not prejudice the future development of such services.
52.260 § 110 The carrier power of ship station transmitters shall not exceed 25 W.
Part B – SECTION I – RR53, RR54 149
ARTICLE 53
Order of priority of communications
53.1 § 1 All stations in the maritime mobile service and the maritime mobile-
satellite service shall be capable of offering four levels of priority in the following
order:
1) Distress calls, distress messages, and distress traffic.
2) Urgency communications.
3) Safety communications.
4) Other communications.
53.2 § 2 In a fully automated system, where it is impracticable to offer all four
levels of priority, category 1 shall receive priority until such time as intergovernmental
agreements1 remove exemptions granted for such systems from offering the complete
order of priority.
ARTICLE 54
Selective calling
54.1 § 1 1) Selective calling is designed for automatic station calling and
distress alerting or the transmission of information for the organization of traffic.
54.2 2) Selective calling is carried out using a digital selective calling
system which shall be in accordance with Recommendation ITU-R M.541-9, and may
be in accordance with the most recent version of Recommendation ITU-R
M.493. (WRC-07)
_______________
1 53.2.1 Requirements and performance standards for radio systems and equipment for
maritime distress and safety radiocommunications are developed and adopted by the
International Maritime Organization (IMO).
150 Maritime Manual – SECTION I – RR56
ARTICLE 56
Narrow-band direct-printing telegraphy
56.1 § 1 Stations using narrow-band direct-printing telegraphy shall comply
with the provisions of Articles 51 and 52.
56.2 § 2 The procedures specified in Recommendation ITU-R M.492-6 shall
be employed except in cases of distress, urgency, or safety, in which case alternate or
non-standard procedures may be used. (WRC-07)
56.3 § 3 Before transmitting, a station shall take precautions to ensure that its
emissions will not interfere with transmissions already in progress; if such interference
is likely, the station shall await an appropriate break in the communications in progress.
This obligation does not apply to stations where unattended operation is possible
through automatic means (see No. 47.3).
56.4 § 4 1) For communication between two stations the ARQ mode should
be used when available.
56.5 2) For transmissions from one coast or ship station to two or more
other stations the forward-error-correcting mode should be used when available.
56.6 § 5 The services provided by each station open to public correspondence
shall be indicated in the List of Coast Stations and Special Service Stations (List IV)
and in the List of Ship Stations and Maritime Mobile Service Identity Assignments
(List V), together with information on charging. (WRC-07)
56.7 § 6 Where transmission over the telecommunication channels open to
public correspondence (excluding the telecommunication channels of the mobile
service and of the mobile-satellite service and its feeder links) is involved, the
provisions of the International Telecommunication Regulations and the relevant ITU-T
Recommendations should be taken into account.
Part B – SECTION I – RR57 151
ARTICLE 57
Radiotelephony
57.1 § 1 The procedure detailed in Recommendation ITU-R M.1171 shall be
applicable to radiotelephone stations, except in cases of distress, urgency or
safety. (WRC-07)
57.2 § 2 The radiotelephone public correspondence service provided on ships
should, if possible, be operated on a duplex basis.
57.3 § 3 1) Devices providing for the emission of a signal to indicate that a
call is in progress on a channel may be used in this service on a non-interference basis
to the service provided by coast stations.
57.4 2) The use of devices for continuous or repetitive calling or
identification in a manually operated radiotelephony service is not permitted.
57.5 3) A station may not transmit identical information simultaneously
on two or more frequencies when communicating with only one other station.
57.6 4) A station shall not emit any carrier wave between calls.
However, stations in an automatically operated radiotelephone system may emit
marking signals under the conditions provided for in No. 52.179.
57.7 5) When it is necessary to spell out certain expressions, difficult
words, service abbreviations, figures, etc., the phonetic spelling tables in Appendix 14
shall be used.
57.8 § 4 Calling, and signals preparatory to traffic, shall not exceed one
minute when made on the carrier frequency 2 182 kHz or on 156.8 MHz, except in
cases of distress, urgency or safety. (WRC-07)
57.9 § 5 When it is necessary for a ship station to send signals for testing or
adjustments which are liable to interfere with the working of neighbouring coast
stations, the consent of these stations shall be obtained before such signals are sent.
57.10 § 6 When it is necessary for a station to make test signals, either for the
adjustment of a transmitter before making a call or for the adjustment of a receiver,
such signals shall be kept to a minimum but in any event, shall not exceed ten seconds,
and shall include the call sign or other identification of the station emitting the test
signals. This call sign or other identification shall be spoken slowly and distinctly.
152 Maritime Manual – SECTION I – RR58
ARTICLE 58
Charging and accounting for maritime radiocommunications
58.1 The provisions of the International Telecommunications Regulations,
taking into account ITU-T Recommendations, shall apply.
_______________
SECTION II
Appendices
(Extracts)
Part B – SECTION II – AP1 155
APPENDIX 1 (Rev.WRC-07)
Classification of emissions and necessary bandwidths
(See Article 2)
§ 1 1) Emissions shall be designated according to their necessary bandwidth and
their classification as explained in this Appendix.
2) Formulae and examples of emissions designated in accordance with this
Appendix are given in Recommendation ITU-R SM.1138-1. Further examples may be
provided in other ITU-R Recommendations. These examples may also be published in
the Preface to the International Frequency List. (WRC-07)
Section I – Necessary bandwidth
§ 2 1) The necessary bandwidth, as defined in No. 1.152 and determined in
accordance with the formulae and examples, shall be expressed by three numerals and
one letter. The letter occupies the position of the decimal point and represents the unit
of bandwidth. The first character shall be neither zero nor K, M or G.
2) Necessary bandwidths1:
between 0.001 and 999 Hz shall be expressed in Hz (letter H);
between 1.00 and 999 kHz shall be expressed in kHz (letter K);
between 1.00 and 999 MHz shall be expressed in MHz (letter M);
between 1.00 and 999 GHz shall be expressed in GHz (letter G).
_______________
1 Examples:
0.002 Hz = H002 6 kHz = 6K00 1.25 MHz = 1M25
0.1 Hz = H100 12.5 kHz = 12K5 2 MHz = 2M00
25.3 Hz = 25H3 180.4 kHz = 180K 10 MHz = 10M0
400 Hz = 400H 180.5 kHz = 181K 202 MHz = 202M
2.4 kHz = 2K40 180.7 kHz = 181K 5.65 GHz = 5G65
156 Maritime Manual
3) For the full designation of an emission, the necessary bandwidth,
indicated in four characters, shall be added just before the classification symbols. When
used, the necessary bandwidth shall be determined by one of the following methods:
3.1) use of the formulae and examples of necessary bandwidths and designation
of corresponding emissions given in Recommendation ITU-R
SM.1138-1; (WRC-07)
3.2) computation, in accordance with other ITU-R Recommendations;
3.3) measurement, in cases not covered by § 3.1) or 3.2) above.
Section II – Classification
§ 3 The class of emission is a set of characteristics conforming to § 4 below.
§ 4 Emissions shall be classified and symbolized according to their basic
characteristics as given in Sub-Section IIA and any optional additional characteristics as
provided for in Sub-Section IIB.
§ 5 The basic characteristics (see Sub-Section IIA) are:
1) first symbol – type of modulation of the main carrier;
2) second symbol – nature of signal(s) modulating the main carrier;
3) third symbol – type of information to be transmitted.
Modulation used only for short periods and for incidental purposes (such as, in many
cases, for identification or calling) may be ignored provided that the necessary
bandwidth as indicated is not thereby increased.
Sub-Section IIA – Basic characteristics
§ 6 1) First symbol – Type of modulation of the main carrier
1.1) Emission of an unmodulated carrier N
1.2) Emission in which the main carrier is amplitude-modulated (including
cases where sub-carriers are angle-modulated)
1.2.1) Double-sideband A
1.2.2) Single-sideband, full carrier H
1.2.3) Single-sideband, reduced or variable level carrier R
1.2.4) Single-sideband, suppressed carrier J
Part B – SECTION II – AP1 157
1.2.5) Independent sidebands B
1.2.6) Vestigial sideband C
1.3) Emission in which the main carrier is angle-modulated
1.3.1) Frequency modulation F
1.3.2) Phase modulation G
1.4) Emission in which the main carrier is amplitude- and angle-modulated
either simultaneously or in a pre-established sequence D
1.5) Emission of pulses2
1.5.1) Sequence of unmodulated pulses P
1.5.2) A sequence of pulses
1.5.2.1) modulated in amplitude K
1.5.2.2) modulated in width/duration L
1.5.2.3) modulated in position/phase M
1.5.2.4) in which the carrier is angle-modulated during
the angle-period of the pulse Q
1.5.2.5) which is a combination of the foregoing or is
produced by other means V
1.6) Cases not covered above, in which an emission consists of the main
carrier modulated, either simultaneously or in a pre-established
sequence, in a combination of two or more of the following
modes: amplitude, angle, pulse W
1.7) Cases not otherwise covered
2) Second symbol – Nature of signal(s) modulating the main carrier
2.1) No modulating signal 0
2.2) A single channel containing quantized or digital information without
the use of a modulating sub-carrier3 1
2.3) A single channel containing quantized or digital information with the
use of a modulating sub-carrier3 2
2.4) A single channel containing analogue information 3
_______________
2 Emissions where the main carrier is directly modulated by a signal which has been coded
into quantized form (e.g. pulse code modulation) should be designated under § 1.2) or 1.3).
3 This excludes time-division multiplex.
158 Maritime Manual
2.5) Two or more channels containing quantized or digital information 7
2.6) Two or more channels containing analogue information 8
2.7) Composite system with one or more channels containing quantized or
digital information, together with one or more channels containing
analogue information 9
2.8) Cases not otherwise covered X
3) Third symbol – Type of information to be transmitted4
3.1) No information transmitted N
3.2) Telegraphy – for aural reception A
3.3) Telegraphy – for automatic reception B
3.4) Facsimile C
3.5) Data transmission, telemetry, telecommand D
3.6) Telephony (including sound broadcasting) E
3.7) Television (video) F
3.8) Combination of the above W
3.9) Cases not otherwise covered X
Sub-Section IIB – Optional characteristics for the classification of emissions
§ 7 Two optional characteristics should be added for a more complete description
of an emission. These are:
Fourth symbol – Details of signal(s)
Fifth symbol – Nature of multiplexing
Where the fourth or fifth symbol is used it shall be as indicated below.
Where the fourth or the fifth symbol is not used this should be indicated by a dash
where each symbol would otherwise appear.
1) Fourth symbol – Details of signal(s)
1.1) Two-condition code with elements of differing numbers and/or
durations A
_______________
4 In this context the word “information” does not include information of a constant, unvarying
nature such as is provided by standard frequency emissions, continuous wave and pulse radars,
etc.
Part B – SECTION II – AP1 159
1.2) Two-condition code with elements of the same number and duration
without error-correction B
1.3) Two-condition code with elements of the same number and duration
with error-correction C
1.4) Four-condition code in which each condition represents a signal
element (or one or more bits) D
1.5) Multi-condition code in which each condition represents a signal
element (of one or more bits) E
1.6) Multi-condition code in which each condition or combination of
conditions represents a character F
1.7) Sound of broadcasting quality (monophonic) G
1.8) Sound of broadcasting quality (stereophonic or quadraphonic) H
1.9) Sound of commercial quality (excluding categories given in § 1.10)
and 1.11)) J
1.10) Sound of commercial quality with the use of frequency inversion or
band-splitting K
1.11) Sound of commercial quality with separate frequency-modulated
signals to control the level of demodulated signal L
1.12) Monochrome M
1.13) Colour N
1.14) Combination of the above W
1.15) Cases not otherwise covered X
2) Fifth symbol – Nature of multiplexing
2.1) None N
2.2) Code-division multiplex5 C
2.3) Frequency-division multiplex F
2.4) Time-division multiplex T
2.5) Combination of frequency-division multiplex and time-division
multiplex W
2.6) Other types of multiplexing X
_______________
5 This includes bandwidth expansion techniques.
160 Maritime Manual
APPENDIX 2 (Rev.WRC-03)
Table of transmitter frequency tolerances
(See Article 3)
1 Frequency tolerance is defined in Article 1 and is expressed in parts in 106,
unless otherwise indicated.
2 The power shown for the various categories of stations is the peak envelope
power for single-sideband transmitters and the mean power for all other transmitters,
unless otherwise indicated. The term “power of a radio transmitter” is defined in
Article 1.
3 For technical and operational reasons, certain categories of stations may need
more stringent tolerances than those shown in the table.
Frequency bands
(lower limit exclusive, upper limit inclusive)
and categories of stations
Tolerances applicable
to transmitters
Band: 9 kHz to 535 kHz
1 Fixed stations:
– 9 kHz to 50 kHz
– 50 kHz to 535 kHz
100
50
2 Land stations:
a) Coast stations
b) Aeronautical stations
100 1, 2
100
3 Mobile stations:
a) Ship stations
b) Ship’s emergency transmitters
c) Survival craft stations
d) Aircraft stations
200 3, 4
500 5
500
100
4 Radiodetermination stations 100
5 Broadcasting stations 10 Hz
Band: 535 kHz to 1 606.5 kHz (1 605 kHz in Region 2)
Broadcasting stations
10 Hz (WRC-03)
Part B – SECTION II – AP2 161
Frequency bands
(lower limit exclusive, upper limit inclusive)
and categories of stations
Tolerances applicable
to transmitters
Band: 1 606.5 kHz (1 605 kHz in Region 2) to 4 000 kHz
1 Fixed stations:
– power 200 W or less
– power above 200 W
100 7, 8
50 7, 8
2 Land stations:
– power 200 W or less
– power above 200 W
100 1, 2, 7, 9, 10
50 1, 2, 7, 9, 10
3 Mobile stations:
a) Ship stations
b) Survival craft stations
c) Emergency position-indicating radiobeacons
d) Aircraft stations
e) Land mobile stations
40 Hz 3, 4, 12
100
100
100 10
50 13
4 Radiodetermination stations:
– power 200 W or less
– power above 200 W
20 14
10 14
5 Broadcasting stations 10 Hz 15
Band: 4 MHz to 29.7 MHz
1 Fixed stations:
a) Single-sideband and independent-sideband emissions:
– power 500 W or less
– power above 500 W
b) Class F1B emissions
c) Other classes of emission:
– power 500 W or less
– power above 500 W
50 Hz
20 Hz
10 Hz
20
10
2 Land stations:
a) Coast stations
20 Hz 1, 2, 16
b) Aeronautical stations:
– power 500 W or less
– power above 500 W
c) Base stations
100 10
50 10
20 7
3 Mobile stations:
a) Ship stations:
1) Class A1A emissions
2) Emissions other than Class A1A
b) Survival craft stations
c) Aircraft stations
d) Land mobile stations
10
50 Hz 3, 4, 19
50
100 10
40 20
4 Broadcasting stations 10 Hz 15, 21
5 Space stations 20
6 Earth stations 20
162 Maritime Manual
Frequency bands
(lower limit exclusive, upper limit inclusive)
and categories of stations
Tolerances applicable
to transmitters
Band: 29.7 MHz to 100 MHz
1 Fixed stations:
– power 50 W or less
– power above 50 W
30
20
2 Land stations 20
3 Mobile stations 20 22
4 Radiodetermination stations 50
5 Broadcasting stations (other than television) 2 000 Hz 23
6 Broadcasting stations (television sound and vision) 500 Hz 24, 25
7 Space stations 20
8 Earth stations 20
Band: 100 MHz to 470 MHz
1 Fixed stations:
– power 50 W or less
– power above 50 W
20 26
10
2 Land stations:
a) Coast stations
b) Aeronautical stations
c) Base stations:
– in the band 100-235 MHz
– in the band 235-401 MHz
– in the band 401-470 MHz
10
20 28
15 29
7 29
5 29
3 Mobile stations:
a) Ship stations and survival craft stations:
– in the band 156-174 MHz
– outside the band 156-174 MHz
10
50 31
b) Aircraft stations
c) Land mobile stations:
– in the band 100-235 MHz
– in the band 235-401 MHz
– in the band 401-470 MHz
30 28
15 29
7 29, 32
5 29, 32
4 Radiodetermination stations 50 33
5 Broadcasting stations (other than television) 2 000 Hz 23
6 Broadcasting stations (television sound and vision) 500 Hz 24, 25
7 Space stations 20
8 Earth stations 20
Part B – SECTION II – AP2 163
Frequency bands
(lower limit exclusive, upper limit inclusive)
and categories of stations
Tolerances applicable
to transmitters
Band: 470 MHz to 2 450 MHz
1 Fixed stations:
– power 100 W or less
– power above 100 W
100
50
2 Land stations 20 36
3 Mobile stations 20 36
4 Radiodetermination stations 500 33
5 Broadcasting stations (other than television) 100
6 Broadcasting stations (television sound and vision)
in the band 470 MHz to 960 MHz
500 Hz 24, 25
7 Space stations 20
8 Earth stations 20
Band: 2 450 MHz to 10 500 MHz
1 Fixed stations:
– power 100 W or less
– power above 100 W
200
50
2 Land stations 100
3 Mobile stations 100
4 Radiodetermination stations 1 250 33
5 Space stations 50
6 Earth stations 50
Band: 10.5 GHz to 40 GHz
1 Fixed station 300
2 Radiodetermination stations 5 000 33
3 Broadcasting stations 100
4 Space stations 100
5 Earth stations 100
164 Maritime Manual
Notes in the table of transmitter frequency tolerances
1 For coast station transmitters used for direct-printing telegraphy or for data transmission, the
tolerance is:
– 5 Hz for narrow-band phase-shift keying;
– 15 Hz for frequency-shift keying for transmitters in use or installed before 2 January 1992;
– 10 Hz for frequency-shift keying for transmitters installed after 1 January 1992.
2 For coast station transmitters used for digital selective calling, the tolerance is
10 Hz. (WRC-03)
3 For ship station transmitters used for direct-printing telegraphy or for data transmission, the
tolerance is:
– 5 Hz for narrow-band phase-shift keying;
– 40 Hz for frequency-shift keying for transmitters in use or installed before 2 January 1992;
– 10 Hz for frequency-shift keying for transmitters installed after 1 January 1992.
4 For ship station transmitters used for digital selective calling, the tolerance is
10 Hz. (WRC-03)
5 If the emergency transmitter is used as the reserve transmitter for the main transmitter, the
tolerance for ship station transmitters applies.
7 For single-sideband radiotelephone transmitters except at coast stations, the tolerance is:
– 50 Hz in the bands 1 606.5 (1 605 Region 2)-4 000 kHz and 4-29.7 MHz, for peak
envelope powers of 200 W or less and 500 W or less, respectively;
– 20 Hz in the bands 1 606.5 (1 605 Region 2)-4 000 kHz and 4-29.7 MHz, for peak
envelope powers above 200 W and 500 W, respectively.
8 For radiotelegraphy transmitters with frequency-shift keying the tolerance is 10 Hz.
9 For coast station single-sideband radiotelephone transmitters the tolerance is 20 Hz.
10 For single-sideband transmitters operating in the frequency bands 1 606.5 (1 605 Region 2)-
4 000 kHz and 4-29.7 MHz which are allocated exclusively to the aeronautical mobile (R)
service, the tolerance on the carrier (reference) frequency is:
a) for all aeronautical stations, 10 Hz;
b) for all aircraft stations operating on international services, 20 Hz;
c) for aircraft stations operating exclusively on national services, 50 Hz*.
12 For A1A emissions the tolerance is 50 × 10–6.
13 For transmitters used for single-sideband radiotelephony or for frequency-shift keying
radiotelegraphy the tolerance is 40 Hz.
14 For radiobeacon transmitters in the band 1 606.5 (1 605 Region 2)-1 800 kHz the tolerance is
50 × 10–6.
_______________
* NOTE – In order to achieve maximum intelligibility, it is suggested that administrations
encourage the reduction of this tolerance to 20 Hz.
Part B – SECTION II – AP2 165
15 For A3E emissions with carrier power of 10 kW or less the tolerance is 20 × 10–6, 15 × 10–6
and 10 × 10–6 in the bands 1 606.5 (1 605 Region 2)-4 000 kHz, 4-5.95 MHz and 5.95-
29.7 MHz respectively.
16 For A1A emissions the tolerance is 10 × 10–6.
19 For ship station transmitters in the band 26 175-27 500 kHz, on board small craft, with a
carrier power not exceeding 5 W in or near coastal waters and utilizing F3E and G3E
emissions, the frequency tolerance is 40 × 10–6. (WRC-03)
20 The tolerance is 50 Hz for single-sideband radiotelephone transmitters, except for those
transmitters operating in the band 26 175-27 500 kHz, and not exceeding a peak envelope
power of 15 W, for which the basic tolerance of 40 × 10–6 applies.
21 It is suggested that administrations avoid carrier frequency differences of a few hertz, which
cause degradations similar to periodic fading. This could be avoided if the frequency tolerance
were 0.1 Hz, a tolerance which would be suitable for single-sideband emissions*.
22 For non-vehicular mounted portable equipment with a transmitter mean power not exceeding
5 W, the tolerance is 40 × 10–6.
23 For transmitters of a mean power of 50 W or less operating at frequencies below 108 MHz a
tolerance of 3 000 Hz applies.
24 In the case of television stations of:
– 50 W (vision peak envelope power) or less in the band 29.7-100 MHz;
– 100 W (vision peak envelope power) or less in the band 100-960 MHz;
and which receive their input from other television stations or which serve small isolated
communities, it may not, for operational reasons, be possible to maintain this tolerance. For
such stations, the tolerance is 2 000 Hz.
For stations of 1 W (vision peak envelope power) or less, this tolerance may be relaxed
further to:
– 5 kHz in the band 100-470 MHz;
– 10 kHz in the band 470-960 MHz.
25 For transmitters for system M (NTSC) the tolerance is 1 000 Hz. However, for low power
transmitters using this system Note 24 applies.
26 For multi-hop radio-relay systems employing direct frequency conversion the tolerance is
30 × 10–6.
28 For a channel spacing of 50 kHz the tolerance is 50 × 10–6.
29 These tolerances apply to channel spacings equal to or greater than 20 kHz.
_______________
* NOTE – The single-sideband system adopted for the bands exclusively allocated to HF
broadcasting does not require a frequency tolerance less than 10 Hz. The above-mentioned
degradation occurs when the ratio of wanted-to-interfering signal is well below the required
protection ratio. This remark is equally valid for both double- and single-sideband emissions.
166 Maritime Manual
31 For transmitters used by on-board communication stations a tolerance of 5 × 10–6 shall apply.
32 For non-vehicular mounted portable equipment with a transmitter mean power not exceeding
5 W the tolerance is 15 × 10–6.
33 Where specific frequencies are not assigned to radar stations, the bandwidth occupied by the
emissions of such stations shall be maintained wholly within the band allocated to the service
and the indicated tolerance does not apply.
36 In applying this tolerance administrations should be guided by the latest relevant ITU-R
Recommendations.
Part B – SECTION II – AP3 167
APPENDIX 3 (Rev.WRC-03)
Tables of maximum permitted power levels for spurious
or spurious domain emissions1
(See Article 3)
1 The following sections indicate the maximum permitted levels of certain
unwanted emissions, in terms of power as indicated in the tables, of components
supplied by a transmitter to the antenna transmission line. Section I, which provides
spurious emission limits, is applicable until 1 January 2012 to transmitters installed on
or before 1 January 2003; Section II, which limits emissions in the spurious domain, is
applicable to transmitters installed after 1 January 2003 and to all transmitters after
1 January 2012. The provisions of No. 4.5 apply to unwanted emissions not covered in
Sections I and II.
2 Spurious and spurious domain emissions (covered by Sections I and II) from
any part of the installation, other than the antenna and its transmission line, shall not
have an effect greater than would occur if this antenna system were supplied with the
maximum permitted power at the frequency of that emission.
3 These levels shall not, however, apply to emergency position-indicating
radiobeacon (EPIRB) stations, emergency locator transmitters, ships’ emergency
transmitters, lifeboat transmitters, survival craft stations or maritime transmitters when
used in emergency situations.
4 For technical or operational reasons, more stringent levels than those specified
may be applied to protect specific services in certain frequency bands. The levels
applied to protect these services, such as safety and passive services, shall be those
agreed upon by the appropriate world radiocommunication conference. More stringent
levels may also be fixed by specific agreement between the administrations concerned.
Additionally, special consideration of transmitter spurious or spurious domain
emissions may be required for the protection of safety services, radio astronomy and
space services using passive sensors. Information on the levels of interference
detrimental to radio astronomy, Earth exploration satellites and meteorological passive
sensing is given in the most recent version of Recommendation ITU-R SM.329.
5 Spurious and spurious domain emission limits (covered by Sections I and II)
for combined radiocommunication and information technology equipment are those for
the radiocommunication transmitters. (WRC-03)
_______________
1 Spurious domain emissions are unwanted emissions at frequencies within the spurious
domain.
168 Maritime Manual
Section I – Spurious emission limits for transmitters installed on
or before 1 January 2003 (valid until 1 January 2012)
6 Radar systems are exempt from spurious emission limits under this Section.
The lowest practicable power of spurious emission should be achieved. (WRC-2000)
TABLE I
Attenuation values and absolute mean power levels used to calculate maximum
permitted spurious emission power levels for use with radio equipment
Frequency band containing the
assignment
(lower limit exclusive,
upper limit inclusive)
For any spurious component, the attenuation (mean
power within the necessary bandwidth relative to the
mean power of the spurious component concerned)
shall be at least that specified below and the absolute
mean power levels given shall not be exceeded1
9 kHz to 30 MHz 40 dB
50 mW 2, 3, 4
30 MHz to 235 MHz
– mean power above 25 W 60 dB
1 mW 5
– mean power 25 W or less 40 dB
25 µW
235 MHz to 960 MHz
– mean power above 25 W 60 dB
20 mW 6, 7
– mean power 25 W or less 40 dB
25 µW 6, 7
960 MHz to 17.7 GHz
– mean power above 10 W 50 dB
100 mW 6, 7, 8, 9
– mean power 10 W or less 100 µW 6, 7, 8, 9
Above 17.7 GHz The lowest possible values achievable shall be employed (see Recommendation 66 (Rev.WRC-2000)*).
1 When checking compliance with the provisions of the Table, it shall be verified that the
bandwidth of the measuring equipment is sufficiently wide to accept all significant
components of the spurious emission concerned.
Part B – SECTION II – AP3 169
TABLE I (end)
2 For mobile transmitters which operate below 30 MHz, any spurious component shall have
an attenuation of at least 40 dB without exceeding the value of 200 mW, but every effort
should be made to comply with the level of 50 mW wherever practicable.
3 For transmitters of a mean power exceeding 50 kW which can operate on two or more
frequencies covering a frequency range approaching an octave or more, while a reduction
below 50 mW is not mandatory, a minimum attenuation of 60 dB shall be provided.
4 For hand-portable equipment of mean power less than 5 W, the attenuation shall be 30 dB,
but every practicable effort should be made to attain 40 dB attenuation.
5 Administrations may adopt a level of 10 mW provided that harmful interference is not
caused.
6 Where several transmitters feed a common antenna or closely spaced antennas on neigh-
bouring frequencies, every practicable effort should be made to comply with the levels
specified.
7 Since these levels may not provide adequate protection for receiving stations in the radio
astronomy and space services, more stringent levels might be considered in each
individual case in the light of the geographical position of the stations concerned.
8 These levels are not applicable to systems using digital modulation techniques, but
may be used as a guide. Values for these systems may be provided by the relevant
ITU-R Recommendations, when available (see Recommendation 66 (Rev.WRC-2000)*).
9 These levels are not applicable to stations in the space services, but the levels of their
spurious emissions should be reduced to the lowest possible values compatible with the
technical and economic constraints to which the equipment is subject. Values for these
systems may be provided by the relevant ITU-R Recommendations, when available
(see Recommendation 66 Rev.WRC-2000)*).
* Note by the Secretariat: This Recommendation was abrogated by WRC-03.
Section II – Spurious domain emission limits for transmitters installed after
1 January 2003 and for all transmitters after 1 January 2012 (WRC-03)
Application of these limits
7 The frequency range of the measurement of spurious domain emissions is from
9 kHz to 110 GHz or the second harmonic if higher. (WRC-03)
8 Except as provided in § 9 and 10 of this Appendix, the spurious domain
emission levels are specified in the following reference bandwidths:
– 1 kHz between 9 kHz and 150 kHz
– 10 kHz between 150 kHz and 30 MHz
170 Maritime Manual
– 100 kHz between 30 MHz and 1 GHz
– 1 MHz above 1 GHz. (WRC-03)
9 The reference bandwidth of all space service spurious domain emissions
should be 4 kHz. (WRC-03)
10 For radar systems, the reference bandwidths for specifying spurious domain
emission levels should be calculated for each particular system. Thus, for the four
general types of radar pulse modulation utilized for radionavigation, radiolocation,
acquisition, tracking and other radiodetermination functions, the reference bandwidth
values are determined using the following:
– for a fixed-frequency, non-pulse-coded radar, the reciprocal of the radar pulse
length, in seconds (e.g. if the radar pulse length is 1 µs, then the reference
bandwidth is 1/(1 µs) = 1 MHz);
– for a fixed-frequency, phase-coded pulsed radar, the reciprocal of the phase
chip length, in seconds (e.g. if the phase-coded chip is 2 µs long, then the
reference bandwidth is 1/(2 µs) = 500 kHz);
– for a frequency modulated (FM) or chirped radar, the square root of the
quantity obtained by dividing the chirp bandwidth in MHz by the pulse length,
in µs (e.g. if the FM is from 1 250 MHz to 1 280 MHz, i.e. 30 MHz, during the
pulse length of 10 µs, then the reference bandwidth is (30 MHz/10 µs)1/2 =
1.73 MHz);
– for radars operating with multiple waveforms, the reference bandwidth for
specifying spurious domain emission levels is determined empirically from
observations of the radar emission and is obtained following the guidance
given in the most recent version of Recommendation ITU-R M.1177.
In the case of radars, for which the bandwidth, as determined using the method above,
is greater than 1 MHz, a reference bandwidth of 1 MHz should be used. (WRC-03)
10bis Guidance regarding the methods of measuring spurious domain emissions is
given in the most recent version of Recommendation ITU-R SM.329. The e.i.r.p.
method specified in this Recommendation should be used when it is not possible to
accurately measure the power supplied to the antenna transmission line, or for specific
applications where the antenna is designed to provide significant attenuation in the
spurious domain. Additionally, the e.i.r.p. method may need some modification for
special cases. Specific guidance regarding the methods of measuring spurious domain
emissions from radar systems is given in the most recent version of Recommendation
ITU-R M.1177.
Part B – SECTION II – AP3 171
To improve measurement accuracy, sensitivity and efficiency, the resolution bandwidth
in which spurious domain emissions are measured can be different from the reference
bandwidth used for specifying spurious domain emission levels. (WRC-03)
11 The emission limits of this Section apply to all emissions, including harmonic
emissions, intermodulation products, frequency conversion products and parasitic
emissions, at frequencies in the spurious domain (see Fig. 1). The upper and lower parts
of the spurious domain extend outward from a boundary determined using
Annex 1. (WRC-03)
AP3-01
FIGURE 1 (WRC-03)
Out-of-band and spurious domains
Unwanted emissions Unwanted emissions
Spurious domainSpurious domain Out-of-banddomain
Out-of-banddomain
Necessarybandwidth
Frequency of the emission
Boundary of the spurious domain
Limits of the necessary bandwidth
11ter For the case of a single satellite operating with more than one transponder in
the same service area, and when considering the limits for spurious domain emissions
as indicated in § 11 of this Appendix, spurious domain emissions from one transponder
may fall on a frequency at which a second, companion transponder is transmitting. In
these situations, the level of spurious domain emissions from the first transponder is
well exceeded by the fundamental or out-of-band domain emissions of the second
transponder. Therefore, the limits of this Appendix should not apply to those emissions
of a satellite that fall within either the necessary bandwidth or the out-of-band domain
of another transponder on the same satellite, in the same service area (see
Fig. 2). (WRC-03)
172 Maritime Manual
AP3-02
! "# $
FIGURE 2
Example of the applicability of spurious domain emission limits
to a satellite transponder
Transponder A Transponder B Transponder C Transponder D
Out-of-band
Out-of-band
Transponders A, B, C and D are operating on the same satellite in the same service
area. Transponder A is not required to meet spurious domain emission limits in
frequency ranges ! and ", but is required to meet them in frequency ranges #
and $. (WRC-03)
12 Examples of applying 43 + 10 log (P) to calculate attenuation
requirements
Where specified in relation to mean power, spurious domain emissions are to be at least
x dB below the total mean power P, i.e. – x dBc. The power P (W) is to be measured in
a bandwidth wide enough to include the total mean power. The spurious domain
emissions are to be measured in the reference bandwidths given in the relevant ITU-R
Recommendations. The measurement of the spurious domain emission power is
independent of the value of necessary bandwidth. Because the absolute emission power
limit, derived from 43 + 10 log (P), can become too stringent for high-power
transmitters, alternative relative powers are also provided in Table II.
Example 1
A land mobile transmitter, with any value of necessary bandwidth, must meet a
spurious domain emission attenuation of 43 + 10 log (P), or 70 dBc, whichever is less
stringent. The reference bandwidths used for specifying spurious domain emission
levels are provided in § 8 to 10 of this Appendix. Applying this in the frequency range
between 30 MHz and 1 GHz gives a reference bandwidth of 100 kHz.
Part B – SECTION II – AP3 173
With a measured total mean power of 10 W:
– Attenuation relative to total mean power = 43 + 10 log (10) = 53 dBc.
– The 53 dBc value is less stringent than the 70 dBc, so the 53 dBc value is used.
– Therefore: Spurious domain emissions must not exceed 53 dBc in a 100 kHz
bandwidth, or converting to an absolute level, they must not exceed
10 dBW – 53 dBc = –43 dBW in a 100 kHz reference bandwidth.
With a measured total mean power of 1 000 W:
– Attenuation relative to total mean power = 43 + 10 log (1 000) = 73 dBc.
– The 73 dBc value is more stringent than the 70 dBc limit, so the 70 dBc value
is used.
– Therefore: Spurious domain emissions must not exceed 70 dBc in a 100 kHz
bandwidth, or converting to an absolute level, they must not exceed
30 dBW – 70 dBc = _ 40 dBW in a 100 kHz reference bandwidth. (WRC-03)
Example 2
A space service transmitter with any value of necessary bandwidth must meet a
spurious domain emission attenuation of 43 + 10 log (P), or 60 dBc, whichever is less
stringent. To measure spurious domain emissions at any frequency, Note 10 to Table II
indicates using a reference bandwidth of 4 kHz.
With a measured total mean power of 20 W:
– Attenuation relative to total mean power = 43 + 10 log (20) = 56 dBc.
– The 56 dBc value is less stringent than the 60 dBc limit, so the 56 dBc value is
used.
– Therefore: Spurious domain emissions must not exceed 56 dBc in a 4 kHz
reference bandwidth, or converting to an absolute level, they must not exceed
13 dBW – 56 dBc = _ 43 dBW in a 4 kHz reference bandwidth. (WRC-03)
174 Maritime Manual
TABLE II (WRC-03)
Attenuation values used to calculate maximum permitted
spurious domain emission power levels for
use with radio equipment
Service category in accordance with
Article 1, or equipment type15
Attenuation (dB) below the power
supplied to the antenna transmission line
All services except those services quoted
below:
43 + 10 log (P), or 70 dBc, whichever is less
stringent
Space services (earth stations)10, 16 43 + 10 log (P), or 60 dBc, whichever is less
stringent
Space services (space stations)10, 17 43 + 10 log (P), or 60 dBc, whichever is less
stringent
Radiodetermination14 43 + 10 log (PEP), or 60 dB, whichever is less
stringent
Broadcast television11 46 + 10 log (P), or 60 dBc, whichever is less
stringent, without exceeding the absolute
mean power level of 1 mW for VHF stations
or 12 mW for UHF stations. However, greater
attenuation may be necessary on a case by
case basis
Broadcast FM 46 + 10 log (P), or 70 dBc, whichever is less
stringent; the absolute mean power level of
1 mW should not be exceeded
Broadcasting at MF/HF 50 dBc; the absolute mean power level of
50 mW should not be exceeded
SSB from mobile stations12 43 dB below PEP
Amateur services operating below 30 MHz
(including those using SSB)16
43 + 10 log (PEP), or 50 dB, whichever is less
stringent
Services operating below 30 MHz, except
space, radiodetermination, broadcast, those
using SSB from mobile stations, and
amateur12
43 + 10 log (X), or 60 dBc, whichever is less
stringent, where X = PEP for SSB modulation,
and X = P for other modulation
Low-power device radio equipment13 56 + 10 log (P), or 40 dBc, whichever is less
stringent
Emergency transmitters18 No limit
Part B – SECTION II – AP3 175
TABLE II (end) (WRC-03)
P: mean power in watts supplied to the antenna transmission line, in accordance with
No. 1.158. When burst transmission is used, the mean power P and the mean power of
any spurious domain emissions are measured using power averaging over the burst
duration.
PEP: peak envelope power in watts supplied to the antenna transmission line, in accordance
with No. 1.157.
dBc: decibels relative to the unmodulated carrier power of the emission. In the cases which do
not have a carrier, for example in some digital modulation schemes where the carrier is
not accessible for measurement, the reference level equivalent to dBc is decibels relative
to the mean power P. 10 Spurious domain emission limits for all space services are stated in a 4 kHz reference
bandwidth. 11 For analogue television transmissions, the mean power level is defined with a specified
video signal modulation. This video signal has to be chosen in such a way that the
maximum mean power level (e.g. at the video signal blanking level for negatively
modulated television systems) is supplied to the antenna transmission line. 12 All classes of emission using SSB are included in the category “SSB”. 13 Low-power radio devices having a maximum output power of less than 100 mW and
intended for short-range communication or control purposes; such equipment is in
general exempt from individual licensing. 14 For radiodetermination systems (radar as defined by No. 1.100), spurious domain
emission attenuation (dB) shall be determined for radiated emission levels, and not at the
antenna transmission line. The measurement methods for determining the radiated
spurious domain emission levels from radar systems should be guided by the most recent
version of Recommendation ITU-R M.1177. (WRC-03)
15 In some cases of digital modulation (including digital broadcasting), broadband systems,
pulsed modulation and narrow-band high-power transmitters for all categories of
services, there may be difficulties in meeting limits close to ± 250% of the necessary
bandwidth. 16 Earth stations in the amateur-satellite service operating below 30 MHz are in the service
category “Amateur services operating below 30 MHz (including those using
SSB)”. (WRC-2000)
17 Space stations in the space research service intended for operation in deep space as
defined by No. 1.177 are exempt from spurious domain emission limits. (WRC-03)
18 Emergency position-indicating radio beacon, emergency locator transmitters, personal
location beacons, search and rescue transponders, ship emergency, lifeboat and survival
craft transmitters and emergency land, aeronautical or maritime transmitters. (WRC-2000)
176 Maritime Manual
ANNEX 1 (WRC-03)
Determination of the boundary between the
out-of-band and spurious domains
1 Except as provided below, the boundary between the out-of-band and spurious
domains occurs at frequencies that are separated from the centre frequency of the
emission by the values shown in Table 1. In general, the boundary, on either side of the
centre frequency, occurs at a separation of 250% of the necessary bandwidth, or at
2.5 BN, as shown in Table 1. For most systems, the centre frequency of the emission is
the centre of the necessary bandwidth. For multichannel or multicarrier
transmitters/transponders, where several carriers may be transmitted simultaneously
from a final output amplifier or an active antenna, the centre frequency of the emission
is taken to be the centre of the –3 dB bandwidth of the transmitter or transponder, and
the transmitter or transponder bandwidth is used in place of the necessary bandwidth for
determining the boundary. For multicarrier satellite systems, guidance on the boundary
between the out-of-band and spurious domains is provided in the most recent version of
Recommendation ITU-R SM.1541. Some systems specify unwanted emissions relative
to channel bandwidth, or channel spacing. These may be used as a substitute for the
necessary bandwidth in Table 1, provided they are found in ITU-R Recommendations.
TABLE 1
Values for frequency separation between the centre frequency
and the boundary of the spurious domain
Frequency
range
Narrow-band case Normal
separation
Wideband case
for BN < Separation for BN > Separation
9 kHz < fc ≤ 150 kHz 250 Hz 625 Hz 2.5 BN 10 kHz 1.5 BN + 10 kHz
150 kHz < fc ≤ 30 MHz 4 kHz 10 kHz 2.5 BN 100 kHz 1.5 BN + 100 kHz
30 MHz < fc ≤ 1 GHz 25 kHz 62.5 kHz 2.5 BN 10 MHz 1.5 BN + 10 MHz
1 GHz < fc ≤ 3 GHz 100 kHz 250 kHz 2.5 BN 50 MHz 1.5 BN + 50 MHz
3 GHz < fc ≤ 10 GHz 100 kHz 250 kHz 2.5 BN 100 MHz 1.5 BN + 100 MHz
10 GHz < fc ≤ 15 GHz 300 kHz 750 kHz 2.5 BN 250 MHz 1.5 BN + 250 MHz
15 GHz < fc ≤ 26 GHz 500 kHz 1.25 MHz 2.5 BN 500 MHz 1.5 BN + 500 MHz
fc > 26 GHz 1 MHz 2.5 MHz 2.5 BN 500 MHz 1.5 BN + 500 MHz
NOTE – In Table 1, fc is the centre frequency of the emission and BN is the necessary bandwidth.
If the assigned frequency band of the emissions extends across two frequency ranges, then the
values corresponding to the higher frequency range shall be used for determining the boundary.
Part B – SECTION II – AP3 177
Example 1: The necessary bandwidth of an emission at 26 MHz is 1.8 kHz. Since BN is
less than 4 kHz, the minimum separation of 10 kHz applies. The spurious domain
begins 10 kHz each side of the centre of the necessary bandwidth.
Example 2: The necessary bandwidth of an emission at 8 GHz is 200 MHz. Since the
wideband case applies for BN > 100 MHz at that frequency, the spurious domain begins
1.5 × 200 MHz + 100 MHz = 400 MHz each side of the centre of the necessary
bandwidth. Using the general separation formula, the out-of-band domain would have
extended to 2.5 × 200 MHz = 500 MHz either side of the centre frequency.
2 Tables 2 and 3 show exceptions to Table 1 for narrow-band and wideband
cases, respectively, applicable to particular systems or services and frequency bands.
TABLE 2
Narrow-band variations for particular systems or services and frequency bands
System or service Frequency range
Narrow-band case
for BN <
(kHz)
Separation
(kHz)
Fixed service
14 kHz-1.5 MHz 20 50(1)
1.5-30 MHz PT ! 50 W 30 75(2)
PT > 50 W 80 200(2)
(1) The separation value is based on an assumption that the maximum value of the necessary
bandwidth is about 3 kHz for the frequency range 14 kHz-1.5 MHz. The separation value of
50 kHz is extremely large as compared with the necessary bandwidth. This is because
unwanted emissions of high power transmitters under modulated conditions have to be
below the spurious limit (70 dBc) at the boundary between the out-of-band and spurious
domains. (2) PT is the transmitter power. The separation values are based on an assumption that the
maximum value of the necessary bandwidth is about 12 kHz for the frequency range 1.5-
30 MHz. The separation value of 200 kHz for PT > 50 W is extremely large as compared
with the necessary bandwidth. This is because unwanted emissions of high power
transmitters under modulated conditions have to be below the spurious limit, 70 dBc, at the
boundary between the out-of-band and spurious domains. Also, if future systems in the fixed
service operating in this frequency range require a necessary bandwidth larger than 12 kHz,
it may become necessary to review the 200 kHz separation.
178 Maritime Manual
TABLE 3
Wideband variations for particular systems or services and frequency bands
3 For primary radar, the boundary between the out-of-band and spurious
domains is the frequency at which the out-of-band domain limits specified in the
applicable ITU-R Recommendations are equal to the spurious domain limit defined in
Table II of this Appendix. Further guidance on the boundary between the out-of-band
and spurious domains for primary radar is provided in the most recent version of
Recommendation ITU-R SM.1541.
System or service Frequency range Wideband case
For BN > Separation
Fixed service 14-150 kHz 20 kHz 1.5 BN + 20 kHz
Fixed-satellite
service (FSS)
3.4-4.2 GHz 250 MHz 1.5 BN + 250 MHz
FSS 5.725-6.725 GHz 500 MHz 1.5 BN + 500 MHz
FSS 7.25-7.75 GHz and 7.9-8.4 GHz 250 MHz 1.5 BN + 250 MHz
FSS 10.7-12.75 GHz 500 MHz 1.5 BN + 500 MHz
Broadcasting-
satellite service
11.7-12.75 GHz 500 MHz 1.5 BN + 500 MHz
FSS 12.75-13.25 GHz 500 MHz 1.5 BN + 500 MHz
FSS 13.75-14.8 GHz 500 MHz 1.5 BN + 500 MHz
Part B – SECTION II – AP9 179
APPENDIX 9
Report of an irregularity or infringement
(See Article 15, Section V)
Particulars concerning the station infringing the Radio Regulations:
1 Name1 if known (in BLOCK letters) ..........................................
2 Call sign or other identification (in BLOCK letters) ..........................................
3 Nationality, if known ..........................................
4 Frequency used (kHz, MHz, GHz or THz) ..........................................
5 Class of emission2 ..........................................
6 Class of station and nature of service, if known ..........................................
7 Location3, 4, 5
Particulars concerning the station, the centralizing office or inspection service
reporting the irregularity or infringement:
8 Name (in BLOCK letters) ..........................................
9 Call sign or other identification (in BLOCK letters) ..........................................
10 Nationality ..........................................
11 Location3, 4 ..........................................
Particulars of the irregularity or infringement:
12 Name6 of the station (in BLOCK letters) in
communication with the station committing the
irregularity or infringement ..........................................
13 Call sign or other identification (in BLOCK letters)
of the station in communication with the station
committing the irregularity or infringement ..........................................
180 Maritime Manual
14 Date and time7 ..........................................
15 Nature of the irregularity or infringement8 ..........................................
16 Extracts from ship log or other information
supporting the report ..........................................
Particulars concerning the transmitting station interfered with9:
17 Name of the station (in BLOCK letters) ..........................................
18 Call sign or other identification (in BLOCK letters) ..........................................
19 Frequency assigned (kHz, MHz, GHz or THz) ..........................................
20 Frequency measured at the time of the interference ..........................................
21 Class of emission2 and bandwidth (indicate whether
measured or estimated, or indicate the necessary
bandwidth notified to the Radiocommunication
Bureau) ..........................................
22 Receiving location3, 4 (in BLOCK letters) where the
interference was experienced ..........................................
23 Certificate:
I certify that the foregoing report represents, to the
best of my knowledge, a complete and accurate
account of what took place. ..........................................
Signatures10 ............................................. Date: ..........................................
............................................. ..........................................
Part B – SECTION II – AP9 181
Instructions for filling in this form
1 Each report shall refer to only one station (see Note 6). If it is forwarded as a letter, it
shall be in duplicate, and whenever practicable should be typewritten. It may also be forwarded
as a telegram.
2 The class of emission shall contain the basic characteristics listed in Appendix 1. If
any characteristic cannot be determined, indicate the unknown symbol with a dash. However, if
a station is not able to identify unambiguously whether the modulation is frequency or phase
modulation, indicate frequency modulation (F).
3 In the case of land, fixed, or earth stations, the position shall be expressed in latitude
and longitude (Greenwich). If the position cannot be furnished, the area of operation should be
indicated.
4 In the case of ship or aircraft stations, the position shall be expressed either in latitude
and longitude (Greenwich) or by a true bearing in degrees and distance in nautical miles, or in
kilometres, from some well known place. If the position cannot be furnished, the area of
operation should be indicated.
5 Where space stations are concerned, information shall be furnished on the orbit.
6 If both communicating stations infringe the Regulations, a separate report shall be
made for each of these stations.
7 The time must be expressed as Coordinated Universal Time (UTC) by a group of four
figures (0000 to 2359). If the infringement is prolonged or repeated, the dates and times shall be
shown.
8 A separate report is required for each irregularity or infringement, unless they are
repeated within a short time.
9 This information is to be given only in case of a complaint about interference.
10 This report shall be signed by the operator who has reported the infringement and
countersigned by the Master of the ship or person responsible for the aircraft, or the officer in
charge of the station in the case of an infringement reported by a station of the mobile service.
When the report originates from a centralizing office or from an inspection service, it shall be
signed by the head of that office or service and countersigned by an official of the administration
sending it.
For the use of the administration only
1 Company controlling the installation of the station against
which complaint is made .........................................................................................
2 Name of the operator of the station held responsible for the
irregularity or infringement of the Regulations .......................................................
3 Action taken ........................................................................................................
182 Maritime Manual
APPENDIX 10 (Rev.WRC-07)
Report of harmful interference
(See Article 15, Section VI)
Particulars concerning the station causing the interference:
a Name, call sign or other means of identification ..........................................
b Frequency measured ..........................................
Date: ..........................................
Time (UTC): ..........................................
c Class of emission 1
..........................................
d Bandwidth (indicate whether measured or estimated) ..........................................
e Measured field strength or power flux-density2 ..........................................
Date: ..........................................
Time (UTC): ..........................................
f Observed polarization ..........................................
g Class of station and nature of service ..........................................
h Location/position/area/bearing (QTE3) (WRC-07) ..........................................
i Location of the facility which made the above
measurements ..........................................
Particulars concerning the transmitting station interfered with:
j Name, call sign or other means of identification ..........................................
k Frequency assigned ..........................................
_______________
1 The class of emission shall contain the basic characteristics listed in Appendix 1. If any
characteristic cannot be determined, indicate the unknown symbol with a dash. However, if a
station is not able to identify unambiguously whether the modulation is frequency or phase
modulation, indicate frequency modulation (F).
2 When measurements are not available, signal strengths according to the QSA scale should be
provided.
3 See the most recent version of Recommendation ITU-R M.1172. (WRC-07)
Part B – SECTION II – AP10 183
l Frequency measured ..........................................
Date: ..........................................
Time (UTC): ..........................................
m Class of emission4 ..........................................
n Bandwidth (indicate whether measured or estimated,
or indicate the necessary bandwidth notified to the
Radiocommunication Bureau) ..........................................
o Location/position/area ..........................................
p Location of the facility which made the above
measurements ..........................................
Particulars furnished by the receiving station experiencing the interference:
q Name of station ..........................................
r Location/position/area ..........................................
s Dates and times (UTC) of occurrence of harmful
interference ..........................................
t Bearings (QTE5) or other particulars (WRC-07) ..........................................
u Nature of interference ..........................................
v Field strength or power flux-density of the wanted
emission at the receiving station experiencing the
interference6 ..........................................
Date: ..........................................
Time (UTC): ..........................................
w Polarization of the receiving antenna or observed
polarization ..........................................
x Action requested ..........................................
NOTE – For convenience and brevity, telegraphic reports shall be in the format above, using the
letters in the order listed in lieu of the explanatory titles, but only those letters for which
information is provided should be used. However, sufficient information shall be provided to the
administration receiving the report, so that an appropriate investigation can be conducted.
_______________
4 See footnote 1.
5 See footnote 3.
6 See footnote 2.
184 Maritime Manual
APPENDIX 12
Special rules applicable to radiobeacons
(See Article 28)
Section II – Maritime Radiobeacons
1) The protection ratio required for assignment of frequencies to
maritime radiobeacons operating in the bands between 283.5 kHz and 335 kHz shall be
based on the effective radiated power being kept to the minimum value necessary to
give the desired field strength at the service range and the need to provide adequate
geographical separation between radiobeacons operating on the same frequency and at
the same time, to avoid harmful interference.
2) The daylight service range of the radiobeacons referred to in § 1)
above shall be based on the following field strengths:
3) Region 1
– 50 µV/m for radiobeacons north of 43° N;
– 75 µV/m for radiobeacons between 43° N and 30° N;
– 100 µV/m for radiobeacons between 30° N and 30° S;
– 75 µV/m for radiobeacons between 30° S and 43° S;
– 50 µV/m for radiobeacons south of 43° S.
4) Region 2
– 50 µV/m for radiobeacons north of 40° N;
– 75 µV/m for radiobeacons between 40° N and 31° N;
– 100 µV/m for radiobeacons between 31° N and 30° S;
– 75 µV/m for radiobeacons between 30° S and 43° S;
– 50 µV/m for radiobeacons south of 43° S.
Part B – SECTION II – AP12 185
5) Region 3
– 75 µV/m for radiobeacons north of 40° N;
– 100 µV/m for radiobeacons between 40° N and 50° S;
– 75 µV/m for radiobeacons south of 50° S.
6) The carrier frequencies of maritime radiobeacons and the separation
between channels shall be based on the use of integer multiples of 100 Hz. The
separation between adjacent carrier frequencies should be based on relevant ITU-R
Recommendations.
186 Maritime Manual
APPENDIX 14 (Rev.WRC-07)
Phonetic alphabet and figure code
(See Articles 32 and 57) (WRC-07)
1 When it is necessary to spell out call signs, service abbreviations and words,
the following letter spelling table shall be used:
Letter to be
transmitted
Code word to be used Spoken as1
A Alfa AL FAH
B Bravo BRAH VOH
C Charlie CHAR LEE or SHAR LEE
D Delta DELL TAH
E Echo ECK OH
F Foxtrot FOKS TROT
G Golf GOLF
H Hotel HOH TELL
I India IN DEE AH
J Juliett JEW LEE ETT
K Kilo KEY LOH
L Lima LEE MAH
M Mike MIKE
N November NO VEM BER
O Oscar OSS CAH
P Papa PAH PAH
Q Quebec KEH BECK
R Romeo ROW ME OH
S Sierra SEE AIR RAH
T Tango TANG GO
U Uniform YOU NEE FORM or
OO NEE FORM
V Victor VIK TAH
W Whiskey WISS KEY
X X-ray ECKS RAY
Y Yankee YANG KEY
Z Zulu ZOO LOO
_______________
1 The syllables to be emphasized are underlined.
Part B – SECTION II – AP14 187
2 When it is necessary to spell out figures or marks, the following table shall be
used:
Figure or mark to
be transmitted
Code word to be used Spoken as2
0 Nadazero NAH-DAH-ZAY-ROH
1 Unaone OO-NAH-WUN
2 Bissotwo BEES-SOH-TOO
3 Terrathree TAY-RAH-TREE
4 Kartefour KAR-TAY-FOWER
5 Pantafive PAN-TAH-FIVE
6 Soxisix SOK-SEE-SIX
7 Setteseven SAY-TAY-SEVEN
8 Oktoeight OK-TOH-AIT
9 Novenine NO-VAY-NINER
Decimal point Decimal DAY-SEE-MAL
Full stop Stop STOP
3 However, stations of the same country, when communicating between
themselves, may use any other table recognized by their administration.
_______________
2 Each syllable should be equally emphasized.
188 Maritime Manual
APPENDIX 15 (Rev.WRC-07)
Frequencies for distress and safety communications for the Global
Maritime Distress and Safety System (GMDSS)
(See Article 31)
The frequencies for distress and safety communications for the GMDSS are given in
Tables 15-1 and 15-2 for frequencies below and above 30 MHz, respectively.
TABLE 15-1 (WRC-07)
Frequencies below 30 MHz
Frequency
(kHz)
Description
of usage Notes
490 MSI The frequency 490 kHz is used exclusively for maritime safety
information (MSI). (WRC-03)
518 MSI The frequency 518 kHz is used exclusively by the international
NAVTEX system.
*2 174.5 NBDP-COM
*2 182 RTP-COM The frequency 2 182 kHz uses class of emission J3E. See also
No. 52.190.
*2 187.5 DSC
3 023 AERO-SAR The aeronautical carrier (reference) frequencies 3 023 kHz and
5 680 kHz may be used for intercommunication between mobile
stations engaged in coordinated search and rescue operations, and
for communication between these stations and participating land
stations, in accordance with the provisions of Appendix 27 (see
Nos. 5.111 and 5.115).
*4 125 RTP-COM See also No. 52.221. The carrier frequency 4 125 kHz may be
used by aircraft stations to communicate with stations of the
maritime mobile service for distress and safety purposes,
including search and rescue (see No. 30.11).
*4 177.5 NBDP-COM
*4 207.5 DSC
4 209.5 MSI The frequency 4 209.5 kHz is exclusively used for NAVTEX-
type transmissions (see Resolution 339 (Rev.WRC-07)).
Part B – SECTION II – AP15 189
TABLE 15-1 (end ) (WRC-07)
Legend:
AERO-SAR These aeronautical carrier (reference) frequencies may be used for distress and
safety purposes by mobile stations engaged in coordinated search and rescue operations.
DSC These frequencies are used exclusively for distress and safety calls using digital
selective calling in accordance with No. 32.5 (see Nos. 33.8 and 33.32). (WRC-07)
MSI In the maritime mobile service, these frequencies are used exclusively for the
transmission of maritime safety information (MSI) (including meteorological and navigational
Frequency
(kHz)
Description
of usage Notes
4 210 MSI-HF
5 680 AERO-SAR See note under 3 023 kHz above.
*6 215 RTP-COM See also No. 52.221.
*6 268 NBDP-COM
*6 312 DSC
6 314 MSI-HF
*8 291 RTP-COM
*8 376.5 NBDP-COM
*8 414.5 DSC
8 416.5 MSI-HF
*12 290 RTP-COM
*12 520 NBDP-COM
*12 577 DSC
12 579 MSI-HF
*16 420 RTP-COM
*16 695 NBDP-COM
*16 804.5 DSC
16 806.5 MSI-HF
19 680.5 MSI-HF
22 376 MSI-HF
26 100.5 MSI-HF
190 Maritime Manual
warnings and urgent information) by coast stations to ships, by means of narrow-band direct-
printing telegraphy.
MSI-HF In the maritime mobile service, these frequencies are used exclusively for the
transmission of high seas MSI by coast stations to ships, by means of narrow-band direct-
printing telegraphy.
NBDP-COM These frequencies are used exclusively for distress and safety communications
(traffic) using narrow-band direct-printing telegraphy.
RTP-COM These carrier frequencies are used for distress and safety communications
(traffic) by radiotelephony.
* Except as provided in these Regulations, any emission capable of causing harmful
interference to distress, alarm, urgency or safety communications on the frequencies denoted by
an asterisk (*) is prohibited. Any emission causing harmful interference to distress and safety
communications on any of the discrete frequencies identified in this Appendix is
prohibited. (WRC-07)
TABLE 15-2 (WRC-07)
Frequencies above 30 MHz (VHF/UHF)
Frequency
(MHz)
Description
of usage Notes
*121.5 AERO-SAR The aeronautical emergency frequency 121.5 MHz is used for
the purposes of distress and urgency for radiotelephony by
stations of the aeronautical mobile service using frequencies in
the band between 117.975 MHz and 137 MHz. This frequency
may also be used for these purposes by survival craft stations.
Emergency position-indicating radio beacons use the frequency
121.5 MHz as indicated in Recommendation ITU-R M.690-1.
Mobile stations of the maritime mobile service may
communicate with stations of the aeronautical mobile service on
the aeronautical emergency frequency 121.5 MHz for the
purposes of distress and urgency only, and on the aeronautical
auxiliary frequency 123.1 MHz for coordinated search and
rescue operations, using class A3E emissions for
both frequencies (see also Nos. 5.111 and 5.200). They shall
then comply with any special arrangement between
governments concerned by which the aeronautical mobile
service is regulated.
Part B – SECTION II – AP15 191
TABLE 15-2 (continued ) (WRC-07)
Frequency
(MHz)
Description
of usage Notes
123.1 AERO-SAR The aeronautical auxiliary frequency 123.1 MHz, which is
auxiliary to the aeronautical emergency frequency 121.5 MHz,
is for use by stations of the aeronautical mobile service and by
other mobile and land stations engaged in coordinated search
and rescue operations (see also No. 5.200).
Mobile stations of the maritime mobile service may
communicate with stations of the aeronautical mobile service on
the aeronautical emergency frequency 121.5 MHz for the
purposes of distress and urgency only, and on the aeronautical
auxiliary frequency 123.1 MHz for coordinated search and
rescue operations, using class A3E emissions for both
frequencies (see also Nos. 5.111 and 5.200). They shall then
comply with any special arrangement between governments
concerned by which the aeronautical mobile service is regulated.
156.3 VHF-CH06 The frequency 156.3 MHz may be used for communication
between ship stations and aircraft stations engaged in
coordinated search and rescue operations. It may also be used by
aircraft stations to communicate with ship stations for other
safety purposes (see also Note f ) in Appendix 18).
*156.525 VHF-CH70 The frequency 156.525 MHz is used in the maritime mobile
service for distress and safety calls using digital selective calling
(see also Nos. 4.9, 5.227, 30.2 and 30.3).
156.650 VHF-CH13 The frequency 156.650 MHz is used for ship-to-ship commu-
nications relating to the safety of navigation in accordance with
Note k) in Appendix 18.
*156.8 VHF-CH16 The frequency 156.8 MHz is used for distress and safety
communications by radiotelephony. Additionally, the frequency
156.8 MHz may be used by aircraft stations for safety purposes
only.
*161.975 AIS-SART
VHF CH AIS 1
AIS 1 is used for AIS search and rescue transmitters (AIS-
SART) for use in search and rescue operations.
*162.025 AIS-SART
VHF CH AIS 2
AIS 2 is used for AIS search and rescue transmitters (AIS-
SART) for use in search and rescue operations.
*406-406.1 406-EPIRB This frequency band is used exclusively by satellite emergency
position-indicating radio beacons in the Earth-to-space direction
(see No. 5.266).
1 530-1 544 SAT-COM In addition to its availability for routine non-safety purposes, the
band 1 530-1 544 MHz is used for distress and safety purposes
in the space-to-Earth direction in the maritime mobile-satellite
service. GMDSS distress, urgency and safety communications
have priority in this band (see No. 5.353A).
192 Maritime Manual
TABLE 15-2 (end ) (WRC-07)
Legend:
AERO-SAR These aeronautical carrier (reference) frequencies may be used for distress and
safety purposes by mobile stations engaged in coordinated search and rescue operations.
D&S-OPS The use of these bands is limited to distress and safety operations of satellite
emergency position-indicating radio beacons (EPIRBs).
SAT-COM These frequency bands are available for distress and safety purposes in the
maritime mobile-satellite service (see Notes).
VHF-CH# These VHF frequencies are used for distress and safety purposes. The channel
number (CH#) refers to the VHF channel as listed in Appendix 18, which should also be
consulted.
AIS These frequencies are used by automatic identification systems (AIS), which
should operate in accordance with the most recent version of Recommendation
ITU-R M.1371. (WRC-07)
* Except as provided in these Regulations, any emission capable of causing harmful
interference to distress, alarm, urgency or safety communications on the frequencies denoted
by an asterisk (*) is prohibited. Any emission causing harmful interference to distress and
safety communications on any of the discrete frequencies identified in this Appendix is
prohibited. (WRC-07)
Frequency
(MHz)
Description
of usage Notes
*1 544-1 545 D&S-OPS Use of the band 1 544-1 545 MHz (space-to-Earth) is limited to
distress and safety operations (see No. 5.356), including feeder
links of satellites needed to relay the emissions of satellite
emergency position-indicating radio beacons to earth stations
and narrow-band (space-to-Earth) links from space stations to
mobile stations.
1 626.5-1 645.5 SAT-COM In addition to its availability for routine non-safety purposes, the
band 1 626.5-1 645.5 MHz is used for distress and safety
purposes in the Earth-to-space direction in the maritime mobile-
satellite service. GMDSS distress, urgency and safety
communications have priority in this band (see No. 5.353A).
*1 645.5-1 646.5 D&S-OPS Use of the band 1 645.5-1 646.5 MHz (Earth-to-space) is limited
to distress and safety operations (see No. 5.375).
9 200-9 500 SARTS This frequency band is used by radar transponders to facilitate
search and rescue.
Part B – SECTION II – AP16 193
APPENDIX 16 (Rev.WRC-07)
Documents with which stations on board ships
and aircraft shall be provided
(See Articles 42 and 51)
Section I – Ship stations for which a Global Maritime Distress and
Safety System installation is required by international agreement
These stations shall be provided with:
1 the licence prescribed by Article 18;
2 certificates of the operator or operators;
3 a log in which the following are recorded as they occur, together with the
time of the occurrence, unless administrations have adopted other arrangements for
recording all information which the log should contain:
a) a summary of communications relating to distress, urgency and safety traffic;
b) a reference to important service incidents;
4 the List of Ship Stations and Maritime Mobile Service Identity
Assignments (see Article 20) in either printed or electronic format;
5 the List of Coast Stations and Special Service Stations (see Article 20) in
either printed or electronic format;
6 the Manual for Use by the Maritime Mobile and Maritime Mobile-
Satellite Services (see Article 20) in either printed or electronic format.
NOTE – An administration may exempt a ship from the carriage of the documents mentioned in
items 5 and 6 above under various circumstances (for example, when that ship carries equivalent
information for the ship’s specified trading area).
Section II – Other ship stations for which a radio installation is required
by regional or international agreement
These stations shall be provided with:
1 the licence prescribed by Article 18;
2 certificates of the operator or operators;
194 Maritime Manual
3 a log or other arrangements which the administration may have adopted
for that purpose, in which a summary of communications related to distress, urgency
and safety traffic shall be recorded together with the time of their occurrence;
4 the List of Coast Stations and Special Service Stations (see Article 20) in
either printed or electronic format;
5 the relevant rules and procedures of radiocommunications, e.g. Manual for
Use by the Maritime Mobile and Maritime Mobile-Satellite Services (paper or
electronic format) (see Article 20).
NOTE – An administration may exempt a ship from the carriage of the documents mentioned in
items 4 and 5 above under various circumstances (for example, when that ship carries equivalent
information for the ship’s specified trading area).
Section III – Other ship stations
These stations shall be provided with:
1 the documents mentioned in items 1 and 2 of Section II;
2 the documents mentioned in items 4 and 5 of Section II, in accordance
with the requirements of the administrations concerned.
NOTE – An administration may exempt a ship from the carriage of the documents mentioned in
item 2 above under various circumstances (for example, when that ship carries equivalent
information for the ship’s specified trading area). Administrations may also, by mutual
agreement, exempt ships travelling only between their national jurisdictions from the licensing
prescribed by Article 18 and the carriage of the documents mentioned in item 1 above, provided
those vessels are otherwise licensed or authorized by regulation.
Section IV – Stations on board aircraft
These stations shall be provided with:
1 the documents mentioned in items 1 and 2 of Section I;
2 a log, unless administrations have adopted other arrangements for
recording all information which the log should contain;
3 those published documents, in either printed or electronic formats,
containing official information relating to stations which the aircraft station may use for
the execution of its service.
Part B – SECTION II – AP17 195
APPENDIX 17 (Rev.WRC-07)
Frequencies and channelling arrangements in the
high-frequency bands for the maritime mobile service
(See Article 52)
PART A – Table of subdivided bands (WRC-07)
In the Table, where appropriate1, the assignable frequencies in a given band for each
usage are:
– indicated by the lowest and highest frequency, in heavy type, assigned in that band;
– regularly spaced, the number of assignable frequencies ( f.) and the spacing in kHz being indicated in italics.
Table of frequencies (kHz) to be used in the band between 4 000 kHz and
27 500 kHz allocated exclusively to the maritime mobile service
_______________
1 Within the non-shaded boxes.
Band (MHz) 4 6 8 12 16 18/19 22 25/26
Limits (kHz) 4 063 6 200 8 195 12 230 16 360 18 780 22 000 25 070
Frequencies assignable
to ship stations for
oceanographic data
transmission c)
4 063.3 to
4 064.8
6 f.
0.3 kHz
Limits (kHz) 4 065 6 200 8 195 12 230 16 360 18 780 22 000 25 070
Frequencies assignable
to ship stations for
telephony, duplex
operation a) i)
4 066.4 to
4 144.4
27 f.
3 kHz
6 201.4
to
6 222.4
8 f.
3 kHz
8 196.4
to
8 292.4
33 f.
3 kHz
12 231.4
to
12 351.4
41 f.
3 kHz
16 361.4
to
16 526.4
56 f.
3 kHz
18 781.4
to
18 823.4
15 f.
3 kHz
22 001.4 to
22 157.4
53 f.
3 kHz
25 071.4 to
25 098.4
10 f.
3 kHz
Limits (kHz) 4 146 6 224 8 294 12 353 16 528 18 825 22 159 25 100
Frequencies assignable
to ship stations and
coast stations for
telephony, simplex
operation
a)
4 147.4 to
4 150.4
2 f. 3 kHz
6 225.4
to
6 231.4
3 f. 3 kHz
8 295.4
to
8 298.4
2 f. 3 kHz
12 354.4
to
12 366.4
5 f. 3 kHz
16 529.4
to
16 547.4
7 f. 3 kHz
18 826.4
to
18 844.4
7 f. 3 kHz
22 160.4 to
22 178.4
7 f. 3 kHz
25 101.4 to
25 119.4
7 f. 3 kHz
Limits (kHz) 4 152 6 233 8 300 12 368 16 549 18 846 22 180 25 121
196 Maritime Manual
Table of frequencies (kHz) to be used in the band between 4 000 kHz and
27 500 kHz allocated exclusively to the maritime mobile service (continued )
Band (MHz) 4 6 8 12 16 18/19 22 25/26
Limits (kHz) 4 152 6 233 8 300 12 368 16 549 18 846 22 180 25 121
Frequencies assignable
to ship stations for
wide-band telegraphy,
facsimile and special
transmission systems
4 154 to
4 170
5 f. 4 kHz
6 235 to
6 259
7 f. 4 kHz
8 302 to
8 338
10 f. 4 kHz
12 370
to
12 418
13 f. 4 kHz
16 551 to
16 615
17 f. 4 kHz
18 848
to
18 868
6 f. 4 kHz
22 182 to
22 238
15 f. 4 kHz
25 123 to
25 159
10 f. 4 kHz
Limits (kHz) 4 172 6 261 8 340 12 420 16 617 18 870 22 240 25 161.25
Frequencies assignable
to ship stations for
oceanographic data
transmission c)
6 261.3
to
6 262.5
5 f. 0.3 kHz
8 340.3
to
8 341.5
5 f. 0.3 kHz
12 420.3
to
12 421.5
5 f. 0.3 kHz
16 617.3
to
16 618.5
5 f. 0.3 kHz
22 240.3 to
22 241.5
5 f. 0.3 kHz
Limits (kHz) 4 172 6 262.75 8 341.75 12 421.75 16 618.75 18 870 22 241.75 25 161.25
Frequencies (paired)
assignable to ship
stations for narrow-
band direct-printing
(NBDP) telegraphy and
data transmission
systems at speeds not
exceeding 100 Bd for
FSK and 200 Bd for
PSK
d) j) m) p)
4 172.5 to
4 181.5
18 f.
0.5 kHz
6 263 to
6 275.5
25 f.
0.5 kHz
Limits (kHz) 4 181.75 6 275.75 8 341.75 12 421.75 16 618.75 18 870 22 241.75 25 161.25
Calling frequencies
assignable to ship
stations for A1A or
A1B Morse telegraphy
g) p)
Limits (kHz) 4 186.75 6 280.75 8 341.75 12 421.75 16 618.75 18 870 22 241.75 25 161.25
Frequencies (paired)
assignable to ship
stations for NBDP
telegraphy and data
transmission systems at
speeds not exceeding
100 Bd for FSK and
200 Bd for PSK
d) m) p)
6 281 to
6 284.5
8 f. 0.5 kHz
Limits (kHz) 4 186.75 6 284.75 8 341.75 12 421.75 16 618.75 18 870 22 241.75 25 161.25
Part B – SECTION II – AP17 197
Table of frequencies (kHz) to be used in the band between 4 000 kHz and
27 500 kHz allocated exclusively to the maritime mobile service (continued )
Band (MHz) 4 6 8 12 16 18/19 22 25/26
Limits (kHz) 4 186.75 6 284.75 8 341.75 12 421.75 16 618.75 18 870 22 241.75 25 161.25
Working frequencies
assignable to ship
stations for A1A or
A1B Morse telegraphy
e) f) p)
4 187 to
4 202
31 f. 0.5 kHz
6 285 to
6 300
31 f. 0.5 kHz
8 342 to
8 365.5
48 f. 0.5 kHz
12 422
to
12 476.5
110 f. 0.5 kHz
16 619 to
16 683
129 f. 0.5 kHz
22 242 to
22 279
75 f. 0.5 kHz
25 161.5 to
25 171
20 f. 0.5 kHz
(WRC-07)
Limits (kHz) 4 202.25 6 300.25 8 365.75 12 476.75 16 683.25 18 870 22 279.25 25 171.25
Calling frequencies
assignable to ship
stations for A1A or
A1B Morse telegraphy
g) p)
Limits (kHz) 4 202.25 6 300.25 8 370.75 12 476.75 16 683.25 18 870 22 284.25 25 172.75
Working frequencies
assignable to ship
stations for A1A or
A1B Morse telegraphy
e) f) p)
8 371 to
8 376
11 f.
0.5 kHz
Limits (kHz) 4 202.25 6 300.25 8 376.25 12 476.75 16 683.25 18 870 22 284.25 25 172.75
Frequencies (paired)
assignable to ship
stations for NBDP
telegraphy and data
transmission systems at
speeds not exceeding
100 bauds for FSK and
200 bauds for PSK
d) j) m) p)
8 376.5
to
8 396
40 f.
0.5 kHz
12 477
to
12 549.5
146 f.
0.5 kHz
16 683.5
to
16 733.5
101 f.
0.5 kHz
18 870.5
to
18 892.5
45 f.
0.5 kHz
22 284.5 to
22 351.5
135 f.
0.5 kHz
25 173 to
25 192.5
40 f.
0.5 kHz
Limits (kHz) 4 202.25 6 300.25 8 396.25 12 549.75 16 733.75 18 892.75 22 351.75 25 192.75
Calling frequencies
assignable to ship
stations for A1A or
A1B Morse telegraphy
g) p)
Limits (kHz) 4 202.25 6 300.25 8 396.25 12 554.75 16 738.75 18 892.75 22 351.75 25 192.75
198 Maritime Manual
Table of frequencies (kHz) to be used in the band between 4 000 kHz and
27 500 kHz allocated exclusively to the maritime mobile service (continued )
Band (MHz) 4 6 8 12 16 18/19 22 25/26
Limits (kHz) 4 202.25 6 300.25 8 396.25 12 554.75 16 738.75 18 892.75 22 351.75 25 192.75
Frequencies (paired)
assignable to ship
stations for NBDP
telegraphy and data
transmission systems at
speeds not exceeding
100 bauds for FSK and
200 bauds for PSK
d) m) p)
12 555
to
12 559.5
10 f. 0.5 kHz
16 739 to
16 784.5
92 f. 0.5 kHz
Limits (kHz) 4 202.25 6 300.25 8 396.25 12 559.75 16 784.75 18 892.75 22 351.75 25 192.75
Frequencies (non
paired) assignable to
ship stations for NBDP
telegraphy and data
transmission systems at
speeds not exceeding
100 Bd for FSK and
200 Bd for PSK and for
A1A or A1B Morse
telegraphy (working)
b) p)
4 202.5 to
4 207
10 f.
0.5 kHz
6 300.5
to
6 311.5
23 f.
0.5 kHz
8 396.5
to
8 414
36 f.
0.5 kHz
12 560
to
12 576.5
34 f.
0.5 kHz
16 785 to
16 804
39 f.
0.5 kHz
18 893
to
18 898
11 f.
0.5 kHz
22 352 to
22 374
45 f.
0.5 kHz
25 193 to
25 208
31 f.
0.5 kHz
Limits (kHz) 4 207.25 6 311.75 8 414.25 12 576.75 16 804.25 18 898.25 22 374.25 25 208.25
Frequencies assignable
to ship stations for
digital selective calling
k) l)
4 207.5 to
4 209
4 f. 0.5 kHz
6 312 to
6 313.5
4 f. 0.5 kHz
8 414.5
to
8 416
4 f. 0.5 kHz
12 577
to
12 578.5
4 f. 0.5 kHz
16 804.5
to
16 806
4 f. 0.5 kHz
18 898.5
to
18 899.5
3 f. 0.5 kHz
22 374.5 to
22 375.5
3 f. 0.5 kHz
25 208.5 to
25 209.5
3 f. 0.5 kHz
Limits (kHz) 4 209.25 6 313.75 8 416.25 12 578.75 16 806.25 18 899.75 22 375.75 25 210
Limits (kHz) 4 209.25 6 313.75 8 416.25 12 578.75 16 806.25 19 680.25 22 375.75 26 100.25
Frequencies (paired)
assignable to coast
stations for NBDP and
data transmission
systems, at speeds not
exceeding 100 Bd for
FSK and 200 Bd
for PSK
d) n) o) p)
4 209.5 to
4 219
20 f. 0.5 kHz
6 314 to
6 330.5
34 f. 0.5 kHz
8 416.5
to
8 436
40 f. 0.5 kHz
12 579
to
12 656.5
156 f. 0.5 kHz
16 806.5
to
16 902.5
193 f. 0.5 kHz
19 680.5
to
19 703
46 f. 0.5 kHz
22 376 to
22 443.5
136 f. 0.5 kHz
26 100.5 to
26 120.5
41 f. 0.5 kHz
Limits (kHz) 4 219.25 6 330.75 8 436.25 12 656.75 16 902.75 19 703.25 22 443.75 26 120.75
Part B – SECTION II – AP17 199
Table of frequencies (kHz) to be used in the band between 4 000 kHz and
27 500 kHz allocated exclusively to the maritime mobile service (end )
a) See Part B, Section I.
b) See Part B, Section III.
c) The frequency bands may also be used by buoy stations for oceanographic data
transmission and by stations interrogating these buoys.
d) See Part B, Section II.
e) In the frequency bands to be used by ship stations for A1A Morse telegraphy working at
speeds not exceeding 40 Bd, administrations may assign additional frequencies interleaved
between the assignable frequencies. Any frequencies so assigned shall be multiples of
100 Hz. Administrations shall ensure a uniform distribution of such assignments within
the bands.
f) See Part B, Section V.
g) See Part B, Section IV.
Band (MHz) 4 6 8 12 16 18/19 22 25/26
Limits (kHz) 4 219.25 6 330.75 8 436.25 12 656.75 16 902.75 19 703.25 22 443.75 26 120.75
Frequencies assignable
to coast stations for
digital selective calling
l)
4 219.5 to
4 220.5
3 f.
0.5 kHz
6 331 to
6 332
3 f.
0.5 kHz
8 436.5
to
8 437.5
3 f.
0.5 kHz
12 657
to
12 658
3 f.
0.5 kHz
16 903 to
16 904
3 f.
0.5 kHz
19 703.5
to
19 704.5
3 f.
0.5 kHz
22 444 to
22 445
3 f.
0.5 kHz
26 121 to
26 122
3 f.
0.5 kHz
Limits (kHz) 4 221 6 332.5 8 438 12 658.5 16 904.5 19 705 22 445.5 26 122.5
Frequencies assignable
to coast stations for
wide-band and A1A or
A1B Morse telegraphy,
facsimile, special and
data transmission
systems and direct-
printing telegraphy
systems
Limits (kHz) 4 351 6 501 8 707 13 077 17 242 19 755 22 696 26 145
Frequencies
assignable to coast
stations for
telephony, duplex
operation a)
4 352.4 to
4 436.4
29 f.
3 kHz
6 502.4
to
6 523.4
8 f.
3 kHz
8 708.4
to
8 813.4
36 f.
3 kHz
13 078.4
to
13 198.4
41 f.
3 kHz
17 243.4
to
17 408.4
56 f.
3 kHz
19 756.4
to
19 798.4
15 f.
3 kHz
22 697.4 to
22 853.4
53 f.
3 kHz
26 146.4 to
26 173.4
10 f.
3 kHz
Limits (kHz) 4 438 6 525 8 815 13 200 17 410 19 800 22 855 26 175
200 Maritime Manual
i) For the use of the carrier frequencies 4 125 kHz, 6 215 kHz, 8 291 kHz, 12 290 kHz and
16 420 kHz in these sub-bands by ship and coast stations for distress and safety purposes,
by single-sideband radiotelephony, see Article 31. (WRC-07)
j) For the use of the frequencies 4 177.5 kHz, 6 268 kHz, 8 376.5 kHz, 12 520 kHz and
16 695 kHz in these sub-bands by ship and coast stations for distress and safety purposes,
by NBDP telegraphy, see Article 31.
k) For the use of the frequencies 4 207.5 kHz, 6 312 kHz, 8 414.5 kHz, 12 577 kHz and
16 804.5 kHz in these sub-bands by ship and coast stations for distress and safety
purposes, by digital selective calling, see Article 31.
l) The following paired frequencies (for ship/coast stations) 4 208/4 219.5 kHz,
6 312.5/6 331 kHz, 8 415/8 436.5 kHz, 12 577.5/12 657 kHz, 16 805/16 903 kHz,
18 898.5/19 703.5 kHz, 22 374.5/22 444 kHz and 25 208.5/26 121 kHz are the first choice
international frequencies for digital selective calling (see Article 54).
m) Frequencies from these frequency bands may also be used for A1A or A1B Morse
telegraphy (working) (see Part B, Section II).
n) The frequencies 4 210 kHz, 6 314 kHz, 8 416.5 kHz, 12 579 kHz, 16 806.5 kHz,
19 680.5 kHz, 22 376 kHz and 26 100.5 kHz are the exclusive international frequencies for
the transmission of maritime safety information (MSI) (see Articles 31 and 33).
o) The frequency 4 209.5 kHz is an exclusive international frequency for the transmission of
NAVTEX type information (see Articles 31 and 33).
p) These sub-bands, except the frequencies referred to in Notes j), n) and o), may be used for
the initial testing and the possible future introduction within the maritime mobile service
of new digital technologies. Stations using these sub-bands for this purpose shall not cause
harmful interference to, and shall not claim protection from, other stations operating in
accordance with Article 5.
PART B – Channelling arrangements (WRC-07)
Section I – Radiotelephony
1 Radiotelephone channelling arrangements for the frequencies to be used
by coast and ship stations in the bands allocated to the maritime mobile service are
indicated in the following Sub-Sections:
Sub-Section A – Table of single-sideband transmitting frequencies (kHz) for
duplex (two-frequency) operation;
Sub-Section B – Table of single-sideband transmitting frequencies (kHz) for
simplex (single-frequency) operation and for intership cross-band
(two-frequency) operation;
Part B – SECTION II – AP17 201
Sub-Section C-1 – Table of recommended single-sideband transmitting frequencies
(kHz) for ship stations in the band 4 000-4 063 kHz shared with
the fixed service;
Sub-Section C-2 – Table of recommended single-sideband transmitting frequencies
(kHz) for ship and coast stations in the band 8 100-8 195 kHz
shared with the fixed service.
2 The technical characteristics for single-sideband transmitters are specified
in Recommendation ITU-R M.1173.
3 One or more series of frequencies from Sub-Section A (with the exception
of those frequencies mentioned in § 5 below) may be assigned to each coast station,
which uses these frequencies associated in pairs (see No. 52.226); each pair consists of
a transmitting and a receiving frequency. The series shall be selected with due regard to
the areas served and so as to avoid, as far as possible, harmful interference between the
services of different coast stations.
4 The frequencies in Sub-Section B are provided for worldwide common
use by ships of all categories, according to traffic requirements, for ship transmissions
to coast stations and for intership communication. They are also authorized for
worldwide common use for transmissions by coast stations (simplex operation)
provided the peak envelope power does not exceed 1 kW.
5 The following frequencies in Sub-Section A are allocated for calling
purposes:
– Channel No. 421 in the 4 MHz band;
– Channel No. 606 in the 6 MHz band;
– Channel No. 821 in the 8 MHz band;
– Channel No. 1221 in the 12 MHz band;
– Channel No. 1621 in the 16 MHz band;
– Channel No. 1806 in the 18 MHz band;
– Channel No. 2221 in the 22 MHz band;
– Channel No. 2510 in the 25 MHz band.
Calling on the carrier frequencies 12 290 kHz and 16 420 kHz shall be permitted only to
and from rescue coordination centres (see No. 30.6.1), subject to the safeguards of
Resolution 352 (WRC-03) (see Nos. 52.221A and 52.222A).
The remaining frequencies in Sub-Sections A, B, C-1 and C-2 are working
frequencies. (WRC-03)
202 Maritime Manual
5A For the use of the carrier frequencies:
4 125 kHz (Channel No. 421);
6 215 kHz (Channel No. 606);
8 291 kHz (Channel No. 833);
12 290 kHz (Channel No. 1221);
16 420 kHz (Channel No. 1621);
in Sub-Section A, by coast and ship stations for distress and safety purposes, see
Article 31. (WRC-07)
6 a) Maritime radiotelephone stations using single-sideband emissions in
the bands between 4 000 kHz and 27 500 kHz exclusively allocated to the maritime
mobile service shall operate only on the carrier frequencies shown in the Sub-Sections
A and B and, in the case of analogue radiotelephony, shall be in conformity with the
technical characteristics specified in Recommendation ITU-R M.1173.
b) Ship stations, when using frequencies for single-sideband emissions
in the bands 4 000-4 063 kHz and ship and coast stations, when using frequencies for
single-sideband emissions in the band 8 100-8 195 kHz should operate on the carrier
frequencies indicated in Sub-Sections C-1 and C-2 respectively. In the case of analogue
radiotelephony technical characteristics of the equipment shall be those specified in
Recommendation ITU-R M.1173.
c) Stations, when employing the single-sideband mode for analogue
radiotelephony, shall use only class J3E emissions. For digital communications, class
J2D emissions shall be used. (WRC-03)
7 The channelling plan established in Sub-Section C-2 does not prejudice
the rights of administrations to establish, and to notify assignments to stations in the
maritime mobile service other than those using radiotelephony in the band 8 100-
8 195 kHz, in conformity with the relevant provisions of these Regulations.
Part B – SECTION II – AP17 203
Sub-Section A
Table of single-sideband transmitting frequencies (kHz) for duplex
(two-frequency) operation
4 MHz band
Channel No. Coast stations Ship stations
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
401 4 357 4 358.4 4 065 4 066.4
402 4 360 4 361.4 4 068 4 069.4
403 4 363 4 364.4 4 071 4 072.4
404 4 366 4 367.4 4 074 4 075.4
405 4 369 4 370.4 4 077 4 078.4
406 4 372 4 373.4 4 080 4 081.4
407 4 375 4 376.4 4 083 4 084.4
408 4 378 4 379.4 4 086 4 087.4
409 4 381 4 382.4 4 089 4 090.4
410 4 384 4 385.4 4 092 4 093.4
411 4 387 4 388.4 4 095 4 096.4
412 4 390 4 391.4 4 098 4 099.4
413 4 393 4 394.4 4 101 4 102.4
414 4 396 4 397.4 4 104 4 105.4
415 4 399 4 400.4 4 107 4 108.4
416 4 402 4 403.4 4 110 4 111.4
417 4 405 4 406.4 4 113 4 114.4
418 4 408 4 409.4 4 116 4 117.4
419 4 411 4 412.4 4 119 4 120.4
420 4 414 4 415.4 4 122 4 123.4
421 4 417* 4 418.4
* 4 125
* 4 4 126.4 *
422 4 420 4 421.4 4 128 4 129.4
423 4 423 4 424.4 4 131 4 132.4
424 4 426 4 427.4 4 134 4 135.4
425 4 429 4 430.4 4 137 4 138.4
426 4 432 4 433.4 4 140 4 141.4
427 4 435 4 436.4 4 143 4 144.4
428 1, 3
4 351 4 352.4 – –
429 1, 3
4 354 4 355.4 – –
204 Maritime Manual
(continued )
6 MHz band
Channel No. Coast stations Ship stations
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
601 6 501 6 502.4 6 200 6 201.4
602 6 504 6 505.4 6 203 6 204.4
603 6 507 6 508.4 6 206 6 207.4
604 6 510 6 511.4 6 209 6 210.4
605 6 513 6 514.4 6 212 6 213.4
606 6 516* 6 517.4
* 6 215
* 5 6 216.4 *
607 6 519 6 520.4 6 218 6 219.4
608 6 522 6 523.4 6 221 6 222.4
8 MHz band
Channel No. Coast stations Ship stations
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
801 8 719 8 720.4 8 195 8 196.4
802 8 722 8 723.4 8 198 8 199.4
803 8 725 8 726.4 8 201 8 202.4
804 8 728 8 729.4 8 204 8 205.4
805 8 731 8 732.4 8 207 8 208.4
806 8 734 8 735.4 8 210 8 211.4
807 8 737 8 738.4 8 213 8 214.4
808 8 740 8 741.4 8 216 8 217.4
809 8 743 8 744.4 8 219 8 220.4
810 8 746 8 747.4 8 222 8 223.4
811 8 749 8 750.4 8 225 8 226.4
812 8 752 8 753.4 8 228 8 229.4
813 8 755 8 756.4 8 231 8 232.4
814 8 758 8 759.4 8 234 8 235.4
815 8 761 8 762.4 8 237 8 238.4
816 8 764 8 765.4 8 240 8 241.4
817 8 767 8 768.4 8 243 8 244.4
818 8 770 8 771.4 8 246 8 247.4
819 8 773 8 774.4 8 249 8 250.4
820 8 776 8 777.4 8 252 8 253.4
821 8 779* 8 780.4
* 8 255
* 8 256.4 *
822 8 782 8 783.4 8 258 8 259.4
823 8 785 8 786.4 8 261 8 262.4
824 8 788 8 789.4 8 264 8 265.4
825 8 791 8 792.4 8 267 8 268.4
Part B – SECTION II – AP17 205
(continued )
8 MHz band (end)
Channel No. Coast stations Ship stations
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
826 8 794 8 795.4 8 270 8 271.4
827 8 797 8 798.4 8 273 8 274.4
828 8 800 8 801.4 8 276 8 277.4
829 8 803 8 804.4 8 279 8 280.4
830 8 806 8 807.4 8 282 8 283.4
831 8 809 8 810.4 8 285 8 286.4
832 8 812 8 813.4 8 288 8 289.4
833 8 291 7 8 292.4 8 291
7 8 292.4
834 3, 6
8 707 8 708.4 – –
835 3, 6
8 710 8 711.4 – –
836 3, 6
8 713 8 714.4 – –
837 3, 6
8 716 8 717.4 – –
12 MHz band
Channel No. Coast stations Ship stations
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
1201 13 077 13 078.4 12 230 12 231.4
1202 13 080 13 081.4 12 233 12 234.4
1203 13 083 13 084.4 12 236 12 237.4
1204 13 086 13 087.4 12 239 12 240.4
1205 13 089 13 090.4 12 242 12 243.4
1206 13 092 13 093.4 12 245 12 246.4
1207 13 095 13 096.4 12 248 12 249.4
1208 13 098 13 099.4 12 251 12 252.4
1209 13 101 13 102.4 12 254 12 255.4
1210 13 104 13 105.4 12 257 12 258.4
1211 13 107 13 108.4 12 260 12 261.4
1212 13 110 13 111.4 12 263 12 264.4
1213 13 113 13 114.4 12 266 12 267.4
1214 13 116 13 117.4 12 269 12 270.4
1215 13 119 13 120.4 12 272 12 273.4
1216 13 122 13 123.4 12 275 12 276.4
1217 13 125 13 126.4 12 278 12 279.4
1218 13 128 13 129.4 12 281 12 282.4
1219 13 131 13 132.4 12 284 12 285.4
1220 13 134 13 135.4 12 287 12 288.4
206 Maritime Manual
(continued )
12 MHz band (end)
Channel No. Coast stations Ship stations
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
1221 13 137 * 13 138.4 * 12 290 * 8 12 291.4 *
1222 13 140 13 141.4 12 293 12 294.4
1223 13 143 13 144.4 12 296 12 297.4
1224 13 146 13 147.4 12 299 12 300.4
1225 13 149 13 150.4 12 302 12 303.4
1226 13 152 13 153.4 12 305 12 306.4
1227 13 155 13 156.4 12 308 12 309.4
1228 13 158 13 159.4 12 311 12 312.4
1229 13 161 13 162.4 12 314 12 315.4
1230 13 164 13 165.4 12 317 12 318.4
1231 13 167 13 168.4 12 320 12 321.4
1232 13 170 13 171.4 12 323 12 324.4
1233 13 173 13 174.4 12 326 12 327.4
1234 13 176 13 177.4 12 329 12 330.4
1235 13 179 13 180.4 12 332 12 333.4
1236 13 182 13 183.4 12 335 12 336.4
1237 13 185 13 186.4 12 338 12 339.4
1238 13 188 13 189.4 12 341 12 342.4
1239 13 191 13 192.4 12 344 12 345.4
1240 13 194 13 195.4 12 347 12 348.4
1241 13 197 13 198.4 12 350 12 351.4
16 MHz band
Channel No. Coast stations Ship stations
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
1601 17 242 17 243.4 16 360 16 361.4
1602 17 245 17 246.4 16 363 16 364.4
1603 17 248 17 249.4 16 366 16 367.4
1604 17 251 17 252.4 16 369 16 370.4
1605 17 254 17 255.4 16 372 16 373.4
1606 17 257 17 258.4 16 375 16 376.4
1607 17 260 17 261.4 16 378 16 379.4
1608 17 263 17 264.4 16 381 16 382.4
1609 17 266 17 267.4 16 384 16 385.4
1610 17 269 17 270.4 16 387 16 388.4
Part B – SECTION II – AP17 207
(continued )
16 MHz band (continued )
Channel No. Coast stations Ship stations
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
1611 17 272 17 273.4 16 390 16 391.4
1612 17 275 17 276.4 16 393 16 394.4
1613 17 278 17 279.4 16 396 16 397.4
1614 17 281 17 282.4 16 399 16 400.4
1615 17 284 17 285.4 16 402 16 403.4
1616 17 287 17 288.4 16 405 16 406.4
1617 17 290 17 291.4 16 408 16 409.4
1618 17 293 17 294.4 16 411 16 412.4
1619 17 296 17 297.4 16 414 16 415.4
1620 17 299 17 300.4 16 417 16 418.4
1621 17 302* 17 303.4
* 16 420
* 9 16 421.4 *
1622 17 305 17 306.4 16 423 16 424.4
1623 17 308 17 309.4 16 426 16 427.4
1624 17 311 17 312.4 16 429 16 430.4
1625 17 314 17 315.4 16 432 16 433.4
1626 17 317 17 318.4 16 435 16 436.4
1627 17 320 17 321.4 16 438 16 439.4
1628 17 323 17 324.4 16 441 16 442.4
1629 17 326 17 327.4 16 444 16 445.4
1630 17 329 17 330.4 16 447 16 448.4
1631 17 332 17 333.4 16 450 16 451.4
1632 17 335 17 336.4 16 453 16 454.4
1633 17 338 17 339.4 16 456 16 457.4
1634 17 341 17 342.4 16 459 16 460.4
1635 17 344 17 345.4 16 462 16 463.4
1636 17 347 17 348.4 16 465 16 466.4
1637 17 350 17 351.4 16 468 16 469.4
1638 17 353 17 354.4 16 471 16 472.4
1639 17 356 17 357.4 16 474 16 475.4
1640 17 359 17 360.4 16 477 16 478.4
1641 17 362 17 363.4 16 480 16 481.4
1642 17 365 17 366.4 16 483 16 484.4
1643 17 368 17 369.4 16 486 16 487.4
1644 17 371 17 372.4 16 489 16 490.4
1645 17 374 17 375.4 16 492 16 493.4
1646 17 377 17 378.4 16 495 16 496.4
1647 17 380 17 381.4 16 498 16 499.4
1648 17 383 17 384.4 16 501 16 502.4
1649 17 386 17 387.4 16 504 16 505.4
1650 17 389 17 390.4 16 507 16 508.4
208 Maritime Manual
(continued )
16 MHz band (end )
Channel No. Coast stations Ship stations
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
1651 17 392 17 393.4 16 510 16 511.4
1652 17 395 17 396.4 16 513 16 514.4
1653 17 398 17 399.4 16 516 16 517.4
1654 17 401 17 402.4 16 519 16 520.4
1655 17 404 17 405.4 16 522 16 523.4
1656 17 407 17 408.4 16 525 16 526.4
18/19 MHz band
Channel No. Coast stations Ship stations
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
1801 19 755 19 756.4 18 780 18 781.4
1802 19 758 19 759.4 18 783 18 784.4
1803 19 761 19 762.4 18 786 18 787.4
1804 19 764 19 765.4 18 789 18 790.4
1805 19 767 19 768.4 18 792 18 793.4
1806 19 770* 19 771.4
* 18 795
* 18 796.4 *
1807 19 773 19 774.4 18 798 18 799.4
1808 19 776 19 777.4 18 801 18 802.4
1809 19 779 19 780.4 18 804 18 805.4
1810 19 782 19 783.4 18 807 18 808.4
1811 19 785 19 786.4 18 810 18 811.4
1812 19 788 19 789.4 18 813 18 814.4
1813 19 791 19 792.4 18 816 18 817.4
1814 19 794 19 795.4 18 819 18 820.4
1815 19 797 19 798.4 18 822 18 823.4
22 MHz band
Channel No. Coast stations Ship stations
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
2201 22 696 22 697.4 22 000 22 001.4
2202 22 699 22 700.4 22 003 22 004.4
2203 22 702 22 703.4 22 006 22 007.4
2204 22 705 22 706.4 22 009 22 010.4
2205 22 708 22 709.4 22 012 22 013.4
Part B – SECTION II – AP17 209
(continued )
22 MHz band (continued)
Channel No. Coast stations Ship stations
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
2206 22 711 22 712.4 22 015 22 016.4
2207 22 714 22 715.4 22 018 22 019.4
2208 22 717 22 718.4 22 021 22 022.4
2209 22 720 22 721.4 22 024 22 025.4
2210 22 723 22 724.4 22 027 22 028.4
2211 22 726 22 727.4 22 030 22 031.4
2212 22 729 22 730.4 22 033 22 034.4
2213 22 732 22 733.4 22 036 22 037.4
2214 22 735 22 736.4 22 039 22 040.4
2215 22 738 22 739.4 22 042 22 043.4
2216 22 741 22 742.4 22 045 22 046.4
2217 22 744 22 745.4 22 048 22 049.4
2218 22 747 22 748.4 22 051 22 052.4
2219 22 750 22 751.4 22 054 22 055.4
2220 22 753 22 754.4 22 057 22 058.4
2221 22 756* 22 757.4
* 22 060
* 22 061.4 *
2222 22 759 22 760.4 22 063 22 064.4
2223 22 762 22 763.4 22 066 22 067.4
2224 22 765 22 766.4 22 069 22 070.4
2225 22 768 22 769.4 22 072 22 073.4
2226 22 771 22 772.4 22 075 22 076.4
2227 22 774 22 775.4 22 078 22 079.4
2228 22 777 22 778.4 22 081 22 082.4
2229 22 780 22 781.4 22 084 22 085.4
2230 22 783 22 784.4 22 087 22 088.4
2231 22 786 22 787.4 22 090 22 091.4
2232 22 789 22 790.4 22 093 22 094.4
2233 22 792 22 793.4 22 096 22 097.4
2234 22 795 22 796.4 22 099 22 100.4
2235 22 798 22 799.4 22 102 22 103.4
2236 22 801 22 802.4 22 105 22 106.4
2237 22 804 22 805.4 22 108 22 109.4
2238 22 807 22 808.4 22 111 22 112.4
2239 22 810 22 811.4 22 114 22 115.4
2240 22 813 22 814.4 22 117 22 118.4
2241 22 816 22 817.4 22 120 22 121.4
2242 22 819 22 820.4 22 123 22 124.4
2243 22 822 22 823.4 22 126 22 127.4
2244 22 825 22 826.4 22 129 22 130.4
2245 22 828 22 829.4 22 132 22 133.4
210 Maritime Manual
1 These coast station frequencies may be paired with a ship station frequency from the Table of
simplex frequencies for ship and coast stations (see Sub-Section B) or with a frequency from
the band 4 000-4 063 kHz (see Sub-Section C-1) to be selected by the administration
concerned.
3 These channels may also be used for simplex (single frequency) operation.
4 For the conditions of use of the carrier frequency 4 125 kHz, see Nos. 52.224 and 52.225, and
Appendix 15.
5 For the conditions of use of the carrier frequency 6 215 kHz, see Appendix 15. (WRC-07)
22 MHz band (end )
Channel No. Coast stations Ship stations
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
2246 22 831 22 832.4 22 135 22 136.4
2247 22 834 22 835.4 22 138 22 139.4
2248 22 837 22 838.4 22 141 22 142.4
2249 22 840 22 841.4 22 144 22 145.4
2250 22 843 22 844.4 22 147 22 148.4
2251 22 846 22 847.4 22 150 22 151.4
2252 22 849 22 850.4 22 153 22 154.4
2253 22 852 22 853.4 22 156 22 157.4
25/26 MHz band
Channel No. Coast stations Ship stations
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
2501 26 145 26 146.4 25 070 25 071.4
2502 26 148 26 149.4 25 073 25 074.4
2503 26 151 26 152.4 25 076 25 077.4
2504 26 154 26 155.4 25 079 25 080.4
2505 26 157 26 158.4 25 082 25 083.4
2506 26 160 26 161.4 25 085 25 086.4
2507 26 163 26 164.4 25 088 25 089.4
2508 26 166 26 167.4 25 091 25 092.4
2509 26 169 26 170.4 25 094 25 095.4
2510 26 172* 26 173.4
* 25 097
* 25 098.4 *
Part B – SECTION II – AP17 211
6 These coast station frequencies may be paired with a ship station frequency from the Table of
simplex frequencies for ship and coast stations (see Sub-Section B) or with a frequency from
the band 8 100-8 195 kHz (see Sub-Section C-2) to be selected by the administration
concerned. 7 For the conditions of use of the carrier frequency 8 291 kHz, see Appendix 15. 8 For the conditions of use of the carrier frequency 12 290 kHz, see Nos. 52.221A and 52.222A
and Appendix 15. (WRC-2000) 9 For the conditions of use of the carrier frequency 16 420 kHz, see Nos. 52.221A and 52.222A
and Appendix 15. (WRC-2000) * The frequencies followed by an asterisk are calling frequencies (see Nos. 52.221 and 52.222).
Sub-Section B
Table of single-sideband transmitting frequencies (kHz) for simplex
(single-frequency) operation and for intership cross-band
(two-frequency) operation
(See § 4 of Section I of this Appendix)
4 MHz band1 6 MHz band 8 MHz band2 12 MHz band3
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
4 146
4 149
4 147.4
4 150.4
6 224
6 227
6 230
6 225.4
6 228.4
6 231.4
8 294
8 297
8 295.4
8 298.4
12 353
12 356
12 362
12 365
12 354.4
12 357.4
12 363.4
12 366.4
1 These frequencies may be used for duplex operation with coast stations operating on Channel
Nos. 428 and 429 (see Sub-Section A).
2 These frequencies may be used for duplex operation with coast stations operating on Channel
Nos. 834 up to and including 837 (see Sub-Section A).
3 For use of frequencies 12 359 kHz and 16 537 kHz, see Nos. 52.221A and
52.222A. (WRC-2000)
212 Maritime Manual
3 For use of frequencies 12 359 kHz and 16 537 kHz, see Nos. 52.221A and
52.222A. (WRC-2000)
Sub-Section C-1
Table of recommended single-sideband transmitting frequencies (kHz) for
ship stations in the band 4 000-4 063 kHz shared with the fixed service
The frequencies in this Sub-Section may be used:
– for supplementing ship-to-shore channels for duplex operation in Sub-Section A;
– for intership simplex (single-frequency) and cross-band operation;
– for cross-band working with coast stations on channels in Sub-Section C-2;
– for duplex operation with coast stations working in the band 4 438-4 650 kHz;
– for duplex operation with Channel Nos. 428 and 429.
16 MHz band3 18/19 MHz band 22 MHz band 25/26 MHz band
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
Carrier
frequency
Assigned
frequency
16 528
16 531
16 534
16 540
16 543
16 546
16 529.4
16 532.4
16 535.4
16 541.4
16 544.4
16 547.4
18 825
18 828
18 831
18 834
18 837
18 840
18 843
18 826.4
18 829.4
18 832.4
18 835.4
18 838.4
18 841.4
18 844.4
22 159
22 162
22 165
22 168
22 171
22 174
22 177
22 160.4
22 163.4
22 166.4
22 169.4
22 172.4
22 175.4
22 178.4
25 100
25 103
25 106
25 109
25 112
25 115
25 118
25 101.4
25 104.4
25 107.4
25 110.4
25 113.4
25 116.4
25 119.4
Part B – SECTION II – AP17 213
Sub-Section C-2
Table of recommended single-sideband transmitting frequencies (kHz) for ship
and coast stations in the band 8 100-8 195 kHz shared with the fixed service
(See § 7 of Section I of this Appendix)
The frequencies in this Sub-Section may be used:
– for supplementing ship-to-shore and shore-to-ship channels for duplex operation in
Sub-Section A;
– for intership simplex (single frequency) and cross-band operation;
– for cross-band working with ship stations on channels in Sub-Section C-1;
– for ship-to-shore or shore-to-ship simplex operation;
– for duplex operation with Channel Nos. 834, 835, 836 and 837.
Channel
No.
Carrier
frequency
Assigned
frequency
Channel
No.
Carrier
frequency
Assigned
frequency
1 4 000* 4 001.4* 12 4 033 4 034.4
2 4 003* 4 004.4* 13 4 036 4 037.4
3 4 006 4 007.4 14 4 039 4 040.4
4 4 009 4 010.4 15 4 042 4 043.4
5 4 012 4 013.4 16 4 045 4 046.4
6 4 015 4 016.4 17 4 048 4 049.4
7 4 018 4 019.4 18 4 051 4 052.4
8 4 021 4 022.4 19 4 054 4 055.4
9 4 024 4 025.4 20 4 057 4 058.4
10 4 027 4 028.4 21 4 060 4 061.4
11 4 030 4 031.4
* Administrations are requested to urge ship stations under their jurisdiction to refrain
from using the band 4 000-4 005 kHz when navigating in Region 3 (see also
No. 5.126).
214 Maritime Manual
Section II – Narrow-band direct-printing telegraphy (paired frequencies)
1 Each coast station which uses paired frequencies is assigned one or more
frequency pairs from the following series; each pair consists of a transmitting and a
receiving frequency.
2 The speed of the narrow-band direct-printing telegraphy and data systems shall
not exceed 100 Bd for FSK and 200 Bd for PSK.
Table of frequencies for two-frequency operation by coast stations (kHz)
Channel
No.
Carrier
frequency
Assigned
frequency
Channel
No.
Carrier
frequency
Assigned
frequency
1 8 101 8 102.4 17 8 149 8 150.4
2 8 104 8 105.4 18 8 152 8 153.4
3 8 107 8 108.4 19 8 155 8 156.4
4 8 110 8 111.4 20 8 158 8 159.4
5 8 113 8 114.4 21 8 161 8 162.4
6 8 116 8 117.4 22 8 164 8 165.4
7 8 119 8 120.4 23 8 167 8 168.4
8 8 122 8 123.4 24 8 170 8 171.4
9 8 125 8 126.4 25 8 173 8 174.4
10 8 128 8 129.4 26 8 176 8 177.4
11 8 131 8 132.4 27 8 179 8 180.4
12 8 134 8 135.4 28 8 182 8 183.4
13 8 137 8 138.4 29 8 185 8 186.4
14 8 140 8 141.4 30 8 188 8 189.4
15 8 143 8 144.4 31 8 191 8 192.4
16 8 146 8 147.4
Channel 4 MHz band 1 6 MHz band
38 MHz band
4
No. Transmit Receive Transmit Receive Transmit Receive
1
2
3
4
5
4 210.5
4 211
4 211.5
4 212
4 212.5
4 172.5
4 173
4 173.5
4 174
4 174.5
6 314.5
6 315
6 315.5
6 316
6 316.5
6 263
6 263.5
6 264
6 264.5
6 265
8 376.5 2
8 417
8 417.5
8 418
8 418.5
8 376.5 2
8 377
8 377.5
8 378
8 378.5
6
7
8
9
10
4 213
4 213.5
4 214
4 214.5
4 215
4 175
4 175.5
4 176
4 176.5
4 177
6 317
6 317.5
6 318
6 318.5
6 319
6 265.5
6 266
6 266.5
6 267
6 267.5
8 419
8 419.5
8 420
8 420.5
8 421
8 379
8 379.5
8 380
8 380.5
8 381
Part B – SECTION II – AP17 215
Table of frequencies for two-frequency operation by coast stations (kHz)
Channel 4 MHz band 1 (end) 6 MHz band
3 (end) 8 MHz band 4 (end)
No. Transmit Receive Transmit Receive Transmit Receive
11
12
13
14
15
4 177.52
4 215.5
4 216
4 216.5
4 217
4 177.52
4 178
4 178.5
4 179
4 179.5
6 2682
6 319.5
6 320
6 320.5
6 321
6 2682
6 268.5
6 269
6 269.5
6 270
8 421.5
8 422
8 422.5
8 423
8 423.5
8 381.5
8 382
8 382.5
8 383
8 383.5
16
17
18
19
20
4 217.5
4 218
4 218.5
4 219
4 180
4 180.5
4 181
4 181.5
6 321.5
6 322
6 322.5
6 323
6 323.5
6 270.5
6 271
6 271.5
6 272
6 272.5
8 424
8 424.5
8 425
8 425.5
8 426
8 384
8 384.5
8 385
8 385.5
8 386
21
22
23
24
25
6 324
6 324.5
6 325
6 325.5
6 326
6 273
6 273.5
6 274
6 274.5
6 275
8 426.5
8 427
8 427.5
8 428
8 428.5
8 386.5
8 387
8 387.5
8 388
8 388.5
26
27
28
29
30
6 326.5
6 327
6 327.5
6 328
6 328.5
6 275.5
6 281
6 281.5
6 282
6 282.5
8 429
8 429.5
8 430
8 430.5
8 431
8 389
8 389.5
8 390
8 390.5
8 391
31
32
33
34
35
6 329
6 329.5
6 330
6 330.5
6 283
6 283.5
6 284
6 284.5
8 431.5
8 432
8 432.5
8 433
8 433.5
8 391.5
8 392
8 392.5
8 393
8 393.5
36
37
38
39
40
8 434
8 434.5
8 435
8 435.5
8 436
8 394
8 394.5
8 395
8 395.5
8 396
1 Ship stations may use the coast station receiving frequencies for transmitting A1A or A1B
Morse telegraphy (working), with the exception of channel No. 11 (see Appendix 15).
2 For the conditions of use of this frequency, see Article 31.
3 Ship stations may use the coast station receiving frequencies of channel Nos. 25 up to and
including 34 for transmitting A1A or A1B Morse telegraphy (working).
4 Ship stations may use the coast station receiving frequencies of channel Nos. 29 up to and
including 40 for transmitting A1A or A1B Morse telegraphy (working).
216 Maritime Manual
Table of frequencies for two-frequency operation by coast stations (kHz)
Channel 12 MHz band5 16 MHz band
6 18/19 MHz band
No. Transmit Receive Transmit Receive Transmit Receive
1 2 3 4 5
12 579.5 12 580 12 580.5 12 581 12 581.5
12 477 12 477.512 478 12 478.512 479
16 807 16 807.516 808 16 808.516 809
16 683.516 684 16 684.516 685 16 685.5
19 681 19 681.5 19 682 19 682.5 19 683
18 870.518 871 18 871.518 872 18 872.5
6 7 8 9 10
12 582 12 582.5 12 583 12 583.5 12 584
12 479.512 480 12 480.512 481 12 481.5
16 809.516 810 16 810.516 811 16 811.5
16 686 16 686.516 687 16 687.516 688
19 683.5 19 684 19 684.5 19 685 19 685.5
18 873 18 873.518 874 18 874.518 875
11 12 13 14 15
12 584.5 12 585 12 585.5 12 586 12 586.5
12 482 12 482.512 483 12 483.512 484
16 812 16 812.516 813 16 813.516 814
16 688.516 689 16 689.516 690 16 690.5
19 686 19 686.5 19 687 19 687.5 19 688
18 875.518 876 18 876.518 877 18 877.5
16 17 18 19 20
12 587 12 587.5 12 588 12 588.5 12 589
12 484.512 485 12 485.512 486 12 486.5
16 814.516 815 16 815.516 816 16 816.5
16 691 16 691.516 692 16 692.516 693
19 688.5 19 689 19 689.5 19 690 19 690.5
18 878 18 878.518 879 18 879.518 880
21 22 23 24 25
12 589.5 12 590 12 590.5 12 591 12 591.5
12 487 12 487.512 488 12 488.512 489
16 81716 817.516 818 16 695 2
16 818.5
16 693.516 694 16 694.516 695 2
16 695.5
19 691 19 691.5 19 692 19 692.5 19 693
18 880.518 881 18 881.518 882 18 882.5
26 27 28 29 30
12 592 12 592.5 12 593 12 593.5 12 594
12 489.512 490 12 490.512 491 12 491.5
16 819 16 819.516 820 16 820.516 821
16 696 16 696.516 697 16 697.516 698
19 693.5 19 694 19 694.5 19 695 19 695.5
18 883 18 883.518 884 18 884.518 885
31 32 33 34 35
12 594.5 12 595 12 595.5 12 596 12 596.5
12 492 12 492.512 493 12 493.512 494
16 821.516 822 16 822.516 823 16 823.5
16 698.516 699 16 699.516 700 16 700.5
19 696 19 696.5 19 697 19 697.5 19 698
18 885.518 886 18 886.518 887 18 887.5
36 37 38 39 40
12 597 12 597.5 12 598 12 598.5 12 599
12 494.512 495 12 495.512 496 12 496.5
16 824 16 824.516 825 16 825.516 826
16 701 16 701.516 702 16 702.516 703
19 698.5 19 699 19 699.5 19 700 19 700.5
18 888 18 888.518 889 18 889.518 890
Part B – SECTION II – AP17 217
Table of frequencies for two-frequency operation by coast stations (kHz)
Table of frequencies for two-frequency operation by coast stations (kHz)
Channel 12 MHz band5 (cont.) 16 MHz band
6 (cont.) 18/19 MHz band (end)No. Transmit Receive Transmit Receive Transmit Receive
41 42 43 44 45
12 599.5 12 600 12 600.5 12 601 12 601.5
12 497 12 497.512 498 12 498.512 499
16 826.516 827 16 827.516 828 16 828.5
16 703.516 704 16 704.516 705 16 705.5
19 701 19 701.5 19 702 19 702.5 19 703
18 890.5 18 891 18 891.5 18 892 18 892.5
5 Ship stations may use the coast station receiving frequencies of channel Nos. 58 up to and
including 156 for transmitting A1A or A1B Morse telegraphy (working), with the exception of
channel No. 87 (see Appendix 15).
6 Ship stations may use the coast station receiving frequencies of channel Nos. 71 up to and
including 193 for transmitting A1A or A1B Morse telegraphy (working).
Channel 12 MHz band5 (cont.) 16 MHz band
6 (cont.)
No. Transmit Receive Transmit Receive
46 47 48 49 50
12 602 12 602.5 12 603 12 603.5 12 604
12 499.5 12 500 12 500.5 12 501 12 501.5
16 829 16 829.5 16 830 16 830.5 16 831
16 706 16 706.5 16 707 16 707.5 16 708
51 52 53 54 55
12 604.5 12 605 12 605.5 12 606 12 606.5
12 502 12 502.5 12 503 12 503.5 12 504
16 831.5 16 832 16 832.5 16 833 16 833.5
16 708.5 16 709 16 709.5 16 710 16 710.5
56 57 58 59 60
12 607 12 607.5 12 608 12 608.5 12 609
12 504.5 12 505 12 505.5 12 506 12 506.5
16 834 16 834.5 16 835 16 835.5 16 836
16 711 16 711.5 16 712 16 712.5 16 713
61 62 63 64 65
12 609.5 12 610 12 610.5 12 611 12 611.5
12 507 12 507.5 12 508 12 508.5 12 509
16 836.5 16 837 16 837.5 16 838 16 838.5
16 713.5 16 714 16 714.5 16 715 16 715.5
66 67 68 69 70
12 612 12 612.5 12 613 12 613.5 12 614
12 509.5 12 510 12 510.5 12 511 12 511.5
16 839 16 839.5 16 840 16 840.5 16 841
16 716 16 716.5 16 717 16 717.5 16 718
218 Maritime Manual
Table of frequencies for two-frequency operation by coast stations (kHz)
Channel 12 MHz band5 (cont.) 16 MHz band
6 (cont.)
No. Transmit Receive Transmit Receive
71 72 73 74 75
12 614.5 12 615 12 615.5 12 616 12 616.5
12 512 12 512.5 12 513 12 513.5 12 514
16 841.5 16 842 16 842.5 16 843 16 843.5
16 718.5 16 719 16 719.5 16 720 16 720.5
76 77 78 79 80
12 617 12 617.5 12 618 12 618.5 12 619
12 514.5 12 515 12 515.5 12 516 12 516.5
16 844 16 844.5 16 845 16 845.5 16 846
16 721 16 721.5 16 722 16 722.5 16 723
81 82 83 84 85
12 619.5 12 620 12 620.5 12 621 12 621.5
12 517 12 517.5 12 518 12 518.5 12 519
16 846.5 16 847 16 847.5 16 848 16 848.5
16 723.5 16 724 16 724.5 16 725 16 725.5
86 87 88 89 90
12 622 12 520 2
12 622.5 12 623 12 623.5
12 519.5 12 520 2
12 520.5 12 521 12 521.5
16 849 16 849.5 16 850 16 850.5 16 851
16 726 16 726.5 16 727 16 727.5 16 728
91 92 93 94 95
12 624 12 624.5 12 625 12 625.5 12 626
12 522 12 522.5 12 523 12 523.5 12 524
16 851.5 16 852 16 852.5 16 853 16 853.5
16 728.5 16 729 16 729.5 16 730 16 730.5
96 97 98 99 100
12 626.5 12 627 12 627.5 12 628 12 628.5
12 524.5 12 525 12 525.5 12 526 12 526.5
16 854 16 854.5 16 855 16 855.5 16 856
16 731 16 731.5 16 732 16 732.5 16 733
101 102 103 104 105
12 629 12 629.5 12 630 12 630.5 12 631
12 527 12 527.5 12 528 12 528.5 12 529
16 856.5 16 857 16 857.5 16 858 16 858.5
16 733.5 16 739 16 739.5 16 740 16 740.5
106 107 108 109 110
12 631.5 12 632 12 632.5 12 633 12 633.5
12 529.5 12 530 12 530.5 12 531 12 531.5
16 859 16 859.5 16 860 16 860.5 16 861
16 741 16 741.5 16 742 16 742.5 16 743
Part B – SECTION II – AP17 219
Table of frequencies for two-frequency operation by coast stations (kHz)
Channel 12 MHz band5 (cont.) 16 MHz band
6 (cont.)
No. Transmit Receive Transmit Receive
111 112 113 114 115
12 634 12 634.5 12 635 12 635.5 12 636
12 532 12 532.5 12 533 12 533.5 12 534
16 861.5 16 862 16 862.5 16 863 16 863.5
16 743.5 16 744 16 744.5 16 745 16 745.5
116 117 118 119 120
12 636.5 12 637 12 637.5 12 638 12 638.5
12 534.5 12 535 12 535.5 12 536 12 536.5
16 864 16 864.5 16 865 16 865.5 16 866
16 746 16 746.5 16 747 16 747.5 16 748
121 122 123 124 125
12 639 12 639.5 12 640 12 640.5 12 641
12 537 12 537.5 12 538 12 538.5 12 539
16 866.5 16 867 16 867.5 16 868 16 868.5
16 748.5 16 749 16 749.5 16 750 16 750.5
126 127 128 129 130
12 641.5 12 642 12 642.5 12 643 12 643.5
12 539.5 12 540 12 540.5 12 541 12 541.5
16 869 16 869.5 16 870 16 870.5 16 871
16 751 16 751.5 16 752 16 752.5 16 753
131 132 133 134 135
12 644 12 644.5 12 645 12 645.5 12 646
12 542 12 542.5 12 543 12 543.5 12 544
16 871.5 16 872 16 872.5 16 873 16 873.5
16 753.5 16 754 16 754.5 16 755 16 755.5
136 137 138 139 140
12 646.5 12 647 12 647.5 12 648 12 648.5
12 544.5 12 545 12 545.5 12 546 12 546.5
16 874 16 874.5 16 875 16 875.5 16 876
16 756 16 756.5 16 757 16 757.5 16 758
141 142 143 144 145
12 649 12 649.5 12 650 12 650.5 12 651
12 547 12 547.5 12 548 12 548.5 12 549
16 876.5 16 877 16 877.5 16 878 16 878.5
16 758.5 16 759 16 759.5 16 760 16 760.5
146 147 148 149 150
12 651.5 12 652 12 652.5 12 653 12 653.5
12 549.5 12 555 12 555.5 12 556 12 556.5
16 879 16 879.5 16 880 16 880.5 16 881
16 761 16 761.5 16 762 16 762.5 16 763
220 Maritime Manual
Table of frequencies for two-frequency operation by coast stations (kHz)
Channel 12 MHz band5 (end ) 16 MHz band
6 (end)
No. Transmit Receive Transmit Receive
151 152 153 154 155
12 654 12 654.5 12 655 12 655.5 12 656
12 557 12 557.5 12 558 12 558.5 12 559
16 881.5 16 882 16 882.5 16 883 16 883.5
16 763.5 16 764 16 764.5 16 765 16 765.5
156 157 158 159 160
12 656.5 12 559.5 16 884 16 884.5 16 885 16 885.5 16 886
16 766 16 766.5 16 767 16 767.5 16 768
161 162 163 164 165
16 886.5 16 887 16 887.5 16 888 16 888.5
16 768.5 16 769 16 769.5 16 770 16 770.5
166 167 168 169 170
16 889 16 889.5 16 890 16 890.5 16 891
16 771 16 771.5 16 772 16 772.5 16 773
171 172 173 174 175
16 891.5 16 892 16 892.5 16 893 16 893.5
16 773.5 16 774 16 774.5 16 775 16 775.5
176 177 178 179 180
16 894 16 894.5 16 895 16 895.5 16 896
16 776 16 776.5 16 777 16 777.5 16 778
181 182 183 184 185
16 896.5 16 897 16 897.5 16 898 16 898.5
16 778.5 16 779 16 779.5 16 780 16 780.5
186 187 188 189 190
16 899 16 899.5 16 900 16 900.5 16 901
16 781 16 781.5 16 782 16 782.5 16 783
191 192 193
16 901.5 16 902 16 902.5
16 783.5 16 784 16 784.5
Part B – SECTION II – AP17 221
Table of frequencies for two-frequency operation by coast stations (kHz)
Channel 22 MHz band 7 25/26 MHz band
No. Transmit Receive Transmit Receive
1
2
3
4
5
22 376.5
22 377
22 377.5
22 378
22 378.5
22 284.5
22 285
22 285.5
22 286
22 286.5
26 101
26 101.5
26 102
26 102.5
26 103
25 173
25 173.5
25 174
25 174.5
25 175
6
7
8
9
10
22 379
22 379.5
22 380
22 380.5
22 381
22 287
22 287.5
22 288
22 288.5
22 289
26 103.5
26 104
26 104.5
26 105
26 105.5
25 175.5
25 176
25 176.5
25 177
25 177.5
11
12
13
14
15
22 381.5
22 382
22 382.5
22 383
22 383.5
22 289.5
22 290
22 290.5
22 291
22 291.5
26 106
26 106.5
26 107
26 107.5
26 108
25 178
25 178.5
25 179
25 179.5
25 180
16
17
18
19
20
22 384
22 384.5
22 385
22 385.5
22 386
22 292
22 292.5
22 293
22 293.5
22 294
26 108.5
26 109
26 109.5
26 110
26 110.5
25 180.5
25 181
25 181.5
25 182
25 182.5
21
22
23
24
25
22 386.5
22 387
22 387.5
22 388
22 388.5
22 294.5
22 295
22 295.5
22 296
22 296.5
26 111
26 111.5
26 112
26 112.5
26 113
25 183
25 183.5
25 184
25 184.5
25 185
26
27
28
29
30
22 389
22 389.5
22 390
22 390.5
22 391
22 297
22 297.5
22 298
22 298.5
22 299
26 113.5
26 114
26 114.5
26 115
26 115.5
25 185.5
25 186
25 186.5
25 187
25 187.5
31
32
33
34
35
22 391.5
22 392
22 392.5
22 393
22 393.5
22 299.5
22 300
22 300.5
22 301
22 301.5
26 116
26 116.5
26 117
26 117.5
26 118
25 188
25 188.5
25 189
25 189.5
25 190
36
37
38
39
40
22 394
22 394.5
22 395
22 395.5
22 396
22 302
22 302.5
22 303
22 303.5
22 304
26 118.5
26 119
26 119.5
26 120
26 120.5
25 190.5
25 191
25 191.5
25 192
25 192.5
41
42
43
44
45
22 396.5
22 397
22 397.5
22 398
22 398.5
22 304.5
22 305
22 305.5
22 306
22 306.5
46
47
48
49
50
22 399
22 399.5
22 400
22 400.5
22 401
22 307
22 307.5
22 308
22 308.5
22 309
7 Ship stations may use the coast station receiving frequencies of channels No. 68 up to and
including 135 for transmitting A1A or A1B Morse telegraphy (working).
222 Maritime Manual
Table of frequencies for two-frequency
operation by coast stations (kHz)
Channel 22 MHz band7 (cont.)
No. Transmit Receive
51 52 53 54 55
22 401.5 22 402 22 402.5 22 403 22 403.5
22 309.5 22 310 22 310.5 22 311 22 311.5
56 57 58 59 60
22 404 22 404.5 22 405 22 405.5 22 406
22 312 22 312.5 22 313 22 313.5 22 314
61 62 63 64 65
22 406.5 22 407 22 407.5 22 408 22 408.5
22 314.5 22 315 22 315.5 22 316 22 316.5
66 67 68 69 70
22 409 22 409.5 22 410 22 410.5 22 411
22 317 22 317.5 22 318 22 318.5 22 319
71 72 73 74 75
22 411.5 22 412 22 412.5 22 413 22 413.5
22 319.5 22 320 22 320.5 22 321 22 321.5
76 77 78 79 80
22 414 22 414.5 22 415 22 415.5 22 416
22 322 22 322.5 22 323 22 323.5 22 324
81 82 83 84 85
22 416.5 22 417 22 417.5 22 418 22 418.5
22 324.5 22 325 22 325.5 22 326 22 326.5
86 87 88 89 90
22 419 22 419.5 22 420 22 420.5 22 421
22 327 22 327.5 22 328 22 328.5 22 329
Part B – SECTION II – AP17 223
Table of frequencies for two-frequency
operation by coast stations (kHz)
Channel 22 MHz band7 (end)
No. Transmit Receive
91 92 93 94 95
22 421.5 22 422 22 422.5 22 423 22 423.5
22 329.5 22 330 22 330.5 22 331 22 331.5
96 97 98 99 100
22 424 22 424.5 22 425 22 425.5 22 426
22 332 22 332.5 22 333 22 333.5 22 334
101 102 103 104 105
22 426.5 22 427 22 427.5 22 428 22 428.5
22 334.5 22 335 22 335.5 22 336 22 336.5
106 107 108 109 110
22 429 22 429.5 22 430 22 430.5 22 431
22 337 22 337.5 22 338 22 338.5 22 339
111 112 113 114 115
22 431.5 22 432 22 432.5 22 433 22 433.5
22 339.5 22 340 22 340.5 22 341 22 341.5
116 117 118 119 120
22 434 22 434.5 22 435 22 435.5 22 436
22 342 22 342.5 22 343 22 343.5 22 344
121 122 123 124 125
22 436.5 22 437 22 437.5 22 438 22 438.5
22 344.5 22 345 22 345.5 22 346 22 346.5
126 127 128 129 130
22 439 22 439.5 22 440 22 440.5 22 441
22 347 22 347.5 22 348 22 348.5 22 349
131 132 133 134 135
22 441.5 22 442 22 442.5 22 443 22 443.5
22 349.5 22 350 22 350.5 22 351 22 351.5
224 Maritime Manual
Section III – Narrow-band direct-printing telegraphy
(non-paired frequencies)
1 One or more frequencies are assigned to each ship station as transmitting
frequencies.
2 All frequencies in this Appendix may also be used by ship stations for
transmitting A1A or A1B Morse telegraphy (working).
3 All frequencies appearing in this Appendix may be used for NBDP duplex
operation.
The corresponding coast station frequencies should be selected by the administration
concerned from the sub-bands for coast station wideband telegraphy, A1A or A1B
Morse telegraphy, facsimile, special and data transmission systems and direct-printing
telegraphy systems.
4 The speed of the narrow-band direct-printing telegraphy and data systems shall
not exceed 100 Bd for FSK and 200 Bd for PSK.
Part B – SECTION II – AP17 225
Table of ship station transmitting frequencies (kHz)
Frequency bands
ChannelNo.
4 MHz 6 MHz 8 MHz 12 MHz 16 MHz 18/19MHz
22 MHz 25/26MHz
1
2
3
4
5
4 202.5
4 203
4 203.5
4 204
4 204.5
6 300.5
6 301
6 301.5
6 302
6 302.5
8 396.5
8 397
8 397.5
8 398
8 398.5
12 560
12 560.5
12 561
12 561.5
12 562
16 785
16 785.5
16 786
16 786.5
16 787
18 893
18 893.5
18 894
18 894.5
18 895
22 352
22 352.5
22 353
22 353.5
22 354
25 193
25 193.5
25 194
25 194.5
25 195
6
7
8
9
10
4 205
4 205.5
4 206
4 206.5
4 207
6 303
6 303.5
6 304
6 304.5
6 305
8 399
8 399.5
8 400
8 400.5
8 401
12 562.5
12 563
12 563.5
12 564
12 564.5
16 787.5
16 788
16 788.5
16 789
16 789.5
18 895.5
18 896
18 896.5
18 897
18 897.5
22 354.5
22 355
22 355.5
22 356
22 356.5
25 195.5
25 196
25 196.5
25 197
25 197.5
11
12
13
14
15
6 305.5
6 306
6 306.5
6 307
6 307.5
8 401.5
8 402
8 402.5
8 403
8 403.5
12 565
12 565.5
12 566
12 566.5
12 567
16 790
16 790.5
16 791
16 791.5
16 792
18 898 22 357
22 357.5
22 358
22 358.5
22 359
25 198
25 198.5
25 199
25 199.5
25 200
16
17
18
19
20
6 308
6 308.5
6 309
6 309.5
6 310
8 404
8 404.5
8 405
8 405.5
8 406
12 567.5
12 568
12 568.5
12 569
12 569.5
16 792.5
16 793
16 793.5
16 794
16 794.5
22 359.5
22 360
22 360.5
22 361
22 361.5
25 200.5
25 201
25 201.5
25 202
25 202.5
21
22
23
24
25
6 310.5
6 311
6 311.5
8 406.5
8 407
8 407.5
8 408
8 408.5
12 570
12 570.5
12 571
12 571.5
12 572
16 795
16 795.5
16 796
16 796.5
16 797
22 362
22 362.5
22 363
22 363.5
22 364
25 203
25 203.5
25 204
25 204.5
25 205
26
27
28
29
30
8 409
8 409.5
8 410
8 410.5
8 411
12 572.5
12 573
12 573.5
12 574
12 574.5
16 797.5
16 798
16 798.5
16 799
16 799.5
22 364.5
22 365
22 365.5
22 366
22 366.5
25 205.5
25 206
25 206.5
25 207
25 207.5
31
32
33
34
35
8 411.5
8 412
8 412.5
8 413
8 413.5
12 575
12 575.5
12 576
12 576.5
16 800
16 800.5
16 801
16 801.5
16 802
22 367
22 367.5
22 368
22 368.5
22 369
25 208
36
37
38
39
40
8 414 16 802.5
16 803
16 803.5
16 804
22 369.5
22 370
22 370.5
22 371
22 371.5
226 Maritime Manual
Table of ship station transmitting frequencies (kHz)
Section IV – Morse telegraphy (calling)
Table of calling frequencies assignable to ship stations for A1A or A1B
Morse telegraphy at speeds not exceeding 40 Bd* (kHz)
Frequency bands (end)
ChannelNo.
4 MHz 6 MHz 8 MHz 12 MHz 16 MHz 18/19MHz
22 MHz 25/26MHz
41
42
43
44
45
22 372
22 372.5
22 373
22 373.5
22 374
Group Channel
series 4 MHz band
6 MHzband
8 MHzband
12 MHzband
16 MHzband
22 MHz band
25/26 MHz band
I 1
2
4 182
4 182.5
6 277
6 277.5
8 366
8 366.5
12 550
12 550.5
16 734
16 734.5
22 279.5
22 280
Channel A
25 171.5
Groups I
and II
Common
channel
Common
channel
3
4
4 184
4 184.5
6 276
6 276.5
8 368
8 369
12 552
12 553.5
16 736
16 738
22 280.5
22 281
Common
channel C
25 172
II 5
6
4 183
4 183.5
6 278
6 278.5
8 367
8 367.5
12 551
12 551.5
16 735
16 735.5
22 281.5
22 282
Channel A
25 171.5
Groups I
and II
III 7
8
4 185
4 185.5
6 279
6 279.5
8 368.5
8 369.5
12 552.5
12 553
16 736.5
16 737
22 282.5
22 283
Channel B
25 172.5
IV 9
10
4 186
4 186.5
6 280
6 280.5
8 370
8 370.5
12 554
12 554.5
16 737.5
16 738.5
22 283.5
22 284
Groups III
and IV
* Channel width in every band: 0.5 kHz.
NOTES 1 Only the common channels in the 4, 6, 8, 12 and 16 MHz for A1A Morse telegraphy are harmonically related.
2 Administrations should assign the frequencies as they appear in this Appendix only to ship stations equipped with
cristal controlled oscillators. 3 However, administrations may subdivide each appropriate group channel and common channel into specific calling
frequencies on every full 100 Hz in the channel and assign these discrete frequencies to ships with synthetized
transmitters.
Part B – SECTION II – AP17 227
Examples of subdivision of channels (centre frequencies are underlined)
4 181.8
4 181.9
4 182
4 182.1
4 182.2
6 276.8
6 276.9
6 277
6 277.1
6 277.2
8 365.8
8 365.9
8 366
8 366.1
8 366.2
12 549.8
12 549.9
12 550
12 550.1
12 550.2
16 733.8
16 733.9
16 734
16 734.1
16 734.2
22 279.3
22 279.4
22 279.5
22 279.6
22 279.7
25 171.3
25 171.4
25 171.5
25 171.6
25 171.7
4 Administrations should avoid as far as possible, assigning the two frequencies at ± 100 Hz from the harmonically
related common channel.
5 In the 22 MHz bands and 25/26 MHz bands the channels are not harmonically related to those in the 4 to 16 MHz
bands. However, the principle of subdivision of channels into specific calling frequencies on 100 Hz applies.
Section V – Morse telegraphy (working)
Table of working frequencies (kHz) assignable to ship stations
for A1A or A1B Morse telegraphy at speeds
not exceeding 40 Bd
(See also Part A, Note e))
Frequency bands
Channel
No. 4 MHz 6 MHz 8 MHz 12 MHz 16 MHz 22 MHz 25/26 MHz
1 2 3 4 5
4 187 4 187.5 4 188 4 188.5 4 189
6 285 6 285.5 6 286 6 286.5 6 287
8 342 8 342.58 343 8 343.58 344
12 422 12 422.512 423 12 423.512 424
16 619 16 619.516 620 16 620.516 621
22 242 22 242.5 22 243 22 243.5 22 244
25 161.5 25 162 25 162.5 25 163 25 163.5
6 7 8 9 10
4 189.5 4 190 4 190.5 4 191 4 191.5
6 287.5 6 288 6 288.5 6 289 6 289.5
8 344.58 345 8 345.58 346 8 346.5
12 424.512 425 12 425.512 426 12 426.5
16 621.516 622 16 622.516 623 16 623.5
22 244.5 22 245 22 245.5 22 246 22 246.5
25 164 25 164.5 25 165 25 165.5 25 166
11 12 13 14 15
4 192 4 192.5 4 193 4 193.5 4 194
6 290 6 290.5 6 291 6 291.5 6 292
8 347 8 347.58 348 8 348.58 349
12 427 12 427.512 428 12 428.512 429
16 624 16 624.516 625 16 625.516 626
22 247 22 247.5 22 248 22 248.5 22 249
25 166.5 25 167 25 167.5 25 168 25 168.5
16 17 18 19 20
4 194.5 4 195 4 195.5 4 196 4 196.5
6 292.5 6 293 6 293.5 6 294 6 294.5
8 349.58 350 8 350.58 351 8 351.5
12 429.512 430 12 430.512 431 12 431.5
16 626.516 627 16 627.516 628 16 628.5
22 249.5 22 250 22 250.5 22 251 22 251.5
25 169 25 169.5 25 170 25 170.5 25 171
228 Maritime Manual
Frequency bands (cont.)
Channel
No. 4 MHz 6 MHz 8 MHz 12 MHz 16 MHz 22 MHz 25/26 MHz
21 22 23 24 25
4 197 4 197.5 4 198 4 198.5 4 199
6 295 6 295.5 6 296 6 296.5 6 297
8 352 8 352.58 353 8 353.58 354
12 432 12 432.512 433 12 433.512 434
16 629 16 629.516 630 16 630.516 631
22 252 22 252.5 22 253 22 253.5 22 254
26 27 28 29 30
4 199.5 4 200 4 200.5 4 201 4 201.5
6 297.5 6 298 6 298.5 6 299 6 299.5
8 354.58 355 8 355.58 356 8 356.5
12 434.512 435 12 435.512 436 12 436.5
16 631.516 632 16 632.516 633 16 633.5
22 254.5 22 255 22 255.5 22 256 22 256.5
31 32 33 34 35
4 202 6 300 8 357 8 357.58 358 8 358.58 359
12 437 12 437.512 438 12 438.512 439
16 634 16 634.516 635 16 635.516 636
22 257 22 257.5 22 258 22 258.5 22 259
36 37 38 39 40
8 359.58 360 8 360.58 361 8 361.5
12 439.512 440 12 440.512 441 12 441.5
16 636.516 637 16 637.516 638 16 638.5
22 259.5 22 260 22 260.5 22 261 22 261.5
41 42 43 44 45
8 362 8 362.58 363 8 363.58 364
12 442 12 442.512 443 12 443.512 444
16 639 16 639.516 640 16 640.516 641
22 262 22 262.5 22 263 22 263.5 22 264
46 47 48 49 50
8 364.58 365 8 365.58 371 8 371.5
12 444.512 445 12 445.512 446 12 446.5
16 641.516 642 16 642.516 643 16 643.5
22 264.5 22 265 22 265.5 22 266 22 266.5
51 52 53 54 55
8 372 8 372.58 373 8 373.58 374
12 447 12 447.512 448 12 448.512 449
16 644 16 644.516 645 16 645.516 646
22 267 22 267.5 22 268 22 268.5 22 269
56 57 58 59 60
8 374.58 375 8 375.58 376
12 449.512 450 12 450.512 451 12 451.5
16 646.516 647 16 647.516 648 16 648.5
22 269.5 22 270 22 270.5 22 271 22 271.5
Part B – SECTION II – AP17 229
Frequency bands (cont.)
Channel
No. 4 MHz 6 MHz 8 MHz 12 MHz 16 MHz 22 MHz 25/26 MHz
61 62 63 64 65
12 452 12 452.512 453 12 453.512 454
16 649 16 649.516 650 16 650.516 651
22 272 22 272.5 22 273 22 273.5 22 274
66 67 68 69 70
12 454.512 455 12 455.512 456 12 456.5
16 651.516 652 16 652.516 653 16 653.5
22 274.5 22 275 22 275.5 22 276 22 276.5
71 72 73 74 75
12 457 12 457.512 458 12 458.512 459
16 654 16 654.516 655 16 655.516 656
22 277 22 277.5 22 278 22 278.5 22 279
76 77 78 79 80
12 459.512 460 12 460.512 461 12 461.5
16 656.516 657 16 657.516 658 16 658.5
81 82 83 84 85
12 462 12 462.512 463 12 463.512 464
16 659 16 659.516 660 16 660.516 661
86 87 88 89 90
12 464.512 465 12 465.512 466 12 466.5
16 661.516 662 16 662.516 663 16 663.5
91 92 93 94 95
12 467 12 467.512 468 12 468.512 469
16 664 16 664.516 665 16 665.516 666
96 97 98 99 100
12 469.512 470 12 470.512 471 12 471.5
16 666.516 667 16 667.516 668 16 668.5
230 Maritime Manual
Frequency bands (end)
Channel
No. 4 MHz 6 MHz 8 MHz 12 MHz 16 MHz 22 MHz 25/26 MHz
101 102 103 104 105
12 472 12 472.512 473 12 473.512 474
16 669 16 669.516 670 16 670.516 671
106 107 108 109 110
12 474.512 475 12 475.512 476 12 476.5
16 671.516 672 16 672.516 673 16 673.5
111 112 113 114 115
16 674 16 674.516 675 16 675.516 676
116 117 118 119 120
16 676.516 677 16 677.516 678 16 678.5
121 122 123 124 125
16 679 16 679.516 680 16 680.516 681
126 127 128 129
16 681.516 682 16 682.516 683
Part B – SECTION II – AP18 231
APPENDIX 18 (Rev.WRC-07)
Table of transmitting frequencies in the
VHF maritime mobile band
(See Article 52)
NOTE A – For assistance in understanding the Table, see Notes a) to q ) below. (WRC-07)
NOTE B – The Table below defines the channel numbering for maritime VHF communications
based on 25 kHz channel spacing and use of several duplex channels, but also allows the use of
12.5 kHz channel spacing. The channel numbering for 12.5 kHz channels and the conversion of
two-frequency channels for single-frequency operation shall be in accordance with
Recommendation ITU-R M.1084-4 Annex 4, Tables 1 and 3. (WRC-07)
Channel
designatorNotes
Transmitting
frequencies
(MHz) Inter-
ship
Port operations
and ship movement Public
corres-
pondence From ship
stations
From coast
stations
Single
frequency
Two
frequency
60 m), o) 156.025 160.625 x* x x
01 m), o) 156.050 160.650 x* x x
61 m), o) 156.075 160.675 x x x
02 m), o) 156.100 160.700 x x x
62 m), o) 156.125 160.725 x x x
03 m), o) 156.150 160.750 x x x
63 m), o) 156.175 160.775 x x x
04 m), o) 156.200 160.800 x x x
64 m), o) 156.225 160.825 x x x
05 m), o) 156.250 160.850 x x x
65 m), o) 156.275 160.875 x x x
06 f ) 156.300 x
66 m), o) 156.325 160.925 x* x x
07 m), o) 156.350 160.950 x* x x
67 h) 156.375 156.375 x x
08 156.400 x
68 156.425 156.425 x
09 i) 156.450 156.450 x x
69 156.475 156.475 x x
10 h), q ) 156.500 156.500 x x
70 f), j) 156.525 156.525 Digital selective calling for distress, safety and
calling
232 Maritime Manual – Part B – SECTION II – AP18
Channel
designatorNotes
Transmitting
frequencies
(MHz) Inter-
ship
Port operations
and ship movement Public
corres-
pondence From ship
stations
From coast
stations
Single
frequency
Two
frequency
11 q ) 156.550 156.550 x
71 156.575 156.575 x
12 156.600 156.600 x
72 i) 156.625 x
13 k) 156.650 156.650 x x
73 h), i) 156.675 156.675 x x
14 156.700 156.700 x
74 156.725 156.725 x
15 g) 156.750 156.750 x x
75 n) 156.775 156.775 x
16 f ) 156.800 156.800 DISTRESS, SAFETY AND CALLING
76 n) 156.825 156.825 x
17 g) 156.850 156.850 x x
77 156.875 x
18 m) 156.900 161.500 x x x
78 m) 156.925 161.525 x* x x
19 m) 156.950 161.550 x* x x
79 m) 156.975 161.575 x* x x
20 m) 157.000 161.600 x* x x
80 m) 157.025 161.625 x* x x
21 m) 157.050 161.650 x* x x
81 m) 157.075 161.675 x* x x
22 m) 157.100 161.700 x x x
82 m), o) 157.125 161.725 x x x
23 m), o) 157.150 161.750 x x x
83 m), o) 157.175 161.775 x x x
24 m), o) 157.200 161.800 x x x
84 m), o) 157.225 161.825 x x x
25 m), o) 157.250 161.850 x x x
85 m), o) 157.275 161.875 x x x
26 m), o) 157.300 161.900 x x x
86 m), o) 157.325 161.925 x x x
27 157.350 161.950 x x
87 157.375 157.375 x
Part B – SECTION II – AP18 233
Notes referring to the Table
General notes
a) Administrations may designate frequencies in the inter-ship, port operations and ship
movement services for use by light aircraft and helicopters to communicate with ships or
participating coast stations in predominantly maritime support operations under the conditions
specified in Nos. 51.69, 51.73, 51.74, 51.75, 51.76, 51.77 and 51.78. However, the use of the
channels which are shared with public correspondence shall be subject to prior agreement
between interested and affected administrations.
b) The channels of the present Appendix, with the exception of channels 06, 13, 15, 16, 17, 70,
75 and 76, may also be used for high-speed data and facsimile transmissions, subject to
special arrangement between interested and affected administrations.
c) The channels of the present Appendix, but preferably channel 28 and with the exception of
channels 06, 13, 15, 16, 17, 70, 75 and 76, may be used for direct-printing telegraphy and data
transmission, subject to special arrangement between interested and affected administrations.
d) The frequencies in this table may also be used for radiocommunications on inland waterways
in accordance with the conditions specified in No. 5.226.
e) Administrations may apply 12.5 kHz channel interleaving on a non-interference basis to
25 kHz channels, in accordance with the most recent version of Recommendation
ITU-R M.1084, provided:
– it shall not affect the 25 kHz channels of the present Appendix maritime mobile distress
and safety frequencies, especially the channels 06, 13, 15, 16, 17, and 70, nor the technical
characteristics set forth in Recommendation ITU-R M.489-2 for those channels;
– implementation of 12.5 kHz channel interleaving and consequential national requirements
shall be subject to coordination with affected administrations. (WRC-07)
Channel
designatorNotes
Transmitting
frequencies
(MHz) Inter-
ship
Port operations
and ship movement Public
corres-
pondence From ship
stations
From coast
stations
Single
frequency
Two
frequency
28 157.400 162.000 x x
88 157.425 157.425 x
AIS 1 f ), l), p) 161.975 161.975
AIS 2 f ), l), p) 162.025 162.025
* Note by the Secretariat: Added by the RRB until the necessary action is taken by a future
WRC.
234 Maritime Manual – Part B – SECTION II – AP18
Specific notes
f ) The frequencies 156.300 MHz (channel 06), 156.525 MHz (channel 70), 156.800 MHz
(channel 16), 161.975 MHz (AIS 1) and 162.025 MHz (AIS 2) may also be used by aircraft
stations for the purpose of search and rescue operations and other safety-related
communication. (WRC-07)
g) Channels 15 and 17 may also be used for on-board communications provided the effective
radiated power does not exceed 1 W, and subject to the national regulations of the
administration concerned when these channels are used in its territorial waters.
h) Within the European Maritime Area and in Canada, these frequencies (channels 10, 67, 73)
may also be used, if so required, by the individual administrations concerned, for
communication between ship stations, aircraft stations and participating land stations engaged
in coordinated search and rescue and anti-pollution operations in local areas, under the
conditions specified in Nos. 51.69, 51.73, 51.74, 51.75, 51.76, 51.77 and 51.78.
i) The preferred first three frequencies for the purpose indicated in Note a) are 156.450 MHz
(channel 09), 156.625 MHz (channel 72) and 156.675 MHz (channel 73).
j) Channel 70 is to be used exclusively for digital selective calling for distress, safety and
calling.
k) Channel 13 is designated for use on a worldwide basis as a navigation safety communication
channel, primarily for intership navigation safety communications. It may also be used for the
ship movement and port operations service subject to the national regulations of the
administrations concerned.
l) These channels (AIS 1 and AIS 2) are used for an automatic identification system (AIS)
capable of providing worldwide operation, unless other frequencies are designated on a
regional basis for this purpose. Such use should be in accordance with the most recent version
of Recommendation ITU-R M.1371. (WRC-07)
m) These channels may be operated as single frequency channels, subject to coordination with
affected administrations. (WRC-07)
n) The use of these channels (75 and 76) should be restricted to navigation-related
communications only and all precautions should be taken to avoid harmful interference to
channel 16, e.g. by limiting the output power to 1 W or by means of geographical separation.
o) These channels may be used to provide bands for new technologies, subject to coordination
with affected administrations. Stations using these channels or bands for new technologies
shall not cause harmful interference to, and shall not claim protection from, other stations
operating in accordance with Article 5. The design of such systems shall be such as to
preclude the possibility of interference to the detection of AIS signals on 161.975 or
162.025 MHz. (WRC-07)
p) Additionally, AIS 1 and AIS 2 may be used by the mobile-satellite service (Earth-to-space)
for the reception of AIS transmissions from ships. (WRC-07)
q ) When using these channels (10 and 11), all precautions should be taken to avoid harmful
interference to channel 70. (WRC-07)
SECTION III
Resolutions
(Extracts)
Part B – SECTION III – RES18 237
RESOLUTION 18 (Rev.WRC-07)
Relating to the procedure for identifying and announcing the position
of ships and aircraft of States not parties to an armed conflict1
The World Radiocommunication Conference (Geneva, 2007),
considering
a) that ships and aircraft encounter considerable risk in the vicinity of an area of
armed conflict;
b) that for the safety of life and property it is desirable for ships and aircraft of
States not parties to an armed conflict to be able to identify themselves and announce
their position in such circumstances;
c) that radiocommunication offers such ships and aircraft a rapid means of self-
identification and providing location information prior to their entering areas of armed
conflict and during their passage through the areas;
d) that it is considered desirable to provide a supplementary signal and procedure
for use, in accordance with customary practice, in the area of armed conflict by ships
and aircraft of States representing themselves as not parties to an armed conflict,
resolves
1 that the frequencies for urgency signal and messages specified in the Radio
Regulations may be used by ships and aircraft of States not parties to an armed conflict
for self-identification and establishing communications. The transmission will consist
of the urgency or safety signals, as appropriate, described in Article 33 followed by the
addition of the single group “NNN” in radiotelegraphy and by the addition of the single
word “NEUTRAL” pronounced as in French “neutral” in radiotelephony. As soon as
practicable, communications shall be transferred to an appropriate working frequency;
2 that the use of the signal as described in the preceding paragraph indicates that
the message which follows concerns a ship or aircraft of a State not party to an armed
conflict. The message shall convey at least the following data:
a) call sign or other recognized means of identification of such ship or aircraft;
b) position of such ship or aircraft;
_______________
1 Administrations are invited to study the text of this Resolution and provide any proposals to a
future competent Conference.
238 Maritime Manual
c) number and type of such ships or aircraft;
d) intended route;
e) estimated time en route and of departure and arrival, as appropriate;
f ) any other information, such as flight altitude, radio frequencies guarded,
languages and secondary surveillance radar modes and codes;
3 that the provisions of Article 33 relating to urgency and safety transmissions,
and medical transports shall apply as appropriate to the use of the urgency and safety
signals, respectively, by such ship or aircraft;
4 that the identification and location of ships of a State not party to an armed
conflict may be effected by means of appropriate standard maritime radar transponders.
The identification and location of aircraft of a State not party to an armed conflict may
be effected by the use of the secondary surveillance radar (SSR) system in accordance
with procedures to be recommended by the International Civil Aviation Organization
(ICAO);
5 that the use of the signals described above would not confer or imply
recognition of any rights or duties of a State not party to an armed conflict or a party to
the conflict, except as may be recognized by common agreement between the parties to
the conflict and a non-party;
6 to encourage parties to a conflict to enter into such agreements,
requests the Secretary-General
to communicate the contents of this Resolution to the International Maritime
Organization, the International Civil Aviation Organization, the International
Committee of the Red Cross, and the International Federation of Red Cross and Red
Crescent Societies for such action as they may consider appropriate,
requests ITU-R
to recommend an appropriate signal in the digital selective calling system for use in the
maritime mobile service and other appropriate information as necessary, in consultation
with concerned organizations.
Part B – SECTION III – RES205 239
RESOLUTION 205 (Rev.Mob-87)
Protection of the band 406-406.1 MHz allocated to
the mobile-satellite service1
The World Administrative Radio Conference for the Mobile Services, Geneva, 1987,
considering
a) that WARC-79 allocated the band 406-406.1 MHz to the mobile-satellite
service in the Earth-to-space direction;
b) that Nos. 5.266 and 5.267 limit the use of the band 406-406.1 MHz to low-
power satellite emergency position-indicating radiobeacons (EPIRBs);
c) that WARC Mob-83 made provision in the Radio Regulations for the
introduction and development of a global distress and safety system;
d) that the use of satellite EPIRBs is an essential element of this system;
e) that, like any frequency band reserved for a distress and safety system, the
band 406-406.1 MHz is entitled to full protection against all harmful interference;
f) that WARC Mob-83 adopted Recommendation 604 (Rev.Mob-83)* which
recommends that the ITU-R continue its studies on the technical and operational
questions for EPIRBs, including those using the frequencies in the band 406-
406.1 MHz;
g) that the ITU-R has initiated a study of the compatibility between satellite
EPIRBs in the band 406-406.1 MHz and services using adjacent bands,
considering further
h) that some administrations have developed and implemented an operational
low-altitude, near-polar orbiting satellite system (COSPAS-SARSAT) operating in the
band 406-406.1 MHz to provide alerting and to aid in the locating of distress incidents;
i) that the International Maritime Organization (IMO) has decided that EPIRBs
operating in the COSPAS-SARSAT system will form part of the Global Maritime
Distress and Safety System (GMDSS);
_______________
1 WRC-97 made editorial amendments to this Resolution.
* Note by the Secretariat: This Recommendation was abrogated by WRC-07.
240 Maritime Manual
j) that observations of the use of frequencies in the band 406-406.1 MHz show
that they are being used by stations other than those authorized by No. 5.266, and that
these stations have caused harmful interference to the mobile-satellite service, and
particularly to the reception of satellite EPIRB signals by the COSPAS-SARSAT
system;
k) that in the future, new satellite systems which may be either geostationary or
non-geostationary may be introduced in this band,
recognizing
that it is essential for the protection of human life and property that bands allocated
exclusively to a service for distress and safety purposes be kept free from harmful
interference,
resolves
to instruct the Radiocommunication Bureau
to organize monitoring programmes in the band 406-406.1 MHz in order to identify the
source of any unauthorized emission in that band,
to urge administrations
1 to take part in monitoring programmes requested by the Bureau in accordance
with No. 16.5, in the band 406-406.1 MHz, with a view to identifying and locating
stations of services other than those authorized in the band;
2 to ensure that stations other than those operated under No. 5.266 abstain from
using frequencies in the band 406-406.1 MHz;
3 to take the appropriate measures to eliminate harmful interference caused to
the distress and safety system,
invites the ITU-R
to continue on an urgent basis its study of compatibility between satellite EPIRBs in the
band 406-406.1 MHz and services using adjacent bands.
Part B – SECTION III – RES207 241
RESOLUTION 207 (Rev.WRC-03)
Measures to address unauthorized use of and interference to
frequencies in the bands allocated to the maritime mobile service
and to the aeronautical mobile (R) service
The World Radiocommunication Conference (Geneva, 2003),
considering
a) that the HF frequencies currently used by the aeronautical and maritime
mobile services for distress, safety and other communications, including allotted
operational frequencies, suffer from harmful interference and are often subject to
difficult propagation conditions;
b) that WRC-97 considered some aspects of the use of the HF bands for distress
and safety communications in the context of the Global Maritime Distress and Safety
System (GMDSS), especially with regard to regulatory measures;
c) that unauthorized operations using maritime and aeronautical frequencies in
the HF bands are continuing to increase and are already a serious risk to HF distress,
safety and other communications;
d) that some administrations have resorted to, for example, transmitting warning
messages on operational HF channels as a means of deterring unauthorized users;
e) that provisions of the Radio Regulations prohibit the unauthorized use of
certain safety frequencies for communications other than those related to safety;
f) that enforcing compliance with these regulatory provisions is becoming
increasingly difficult with the availability of low-cost HF single side-band (SSB)
transceivers;
g) that monitoring observations of the use of frequencies in the band 2 170-
2 194 kHz and in the bands allocated exclusively to the maritime mobile service
between 4 063 kHz and 27 500 kHz and to the aeronautical mobile (R) service between
2 850 kHz and 22 000 kHz show that a number of frequencies in these bands are still
being used by stations of other services, many of which are operating in contravention
of No. 23.2;
h) that, in certain situations, HF radio is the sole means of communication for the
maritime mobile service and that certain frequencies in the bands mentioned in
considering g) are reserved for distress and safety purposes;
242 Maritime Manual
i) that, in certain situations, HF radio is the sole means of communication for the
aeronautical mobile (R) service and that this is a safety service;
j) that WRC-2000 and this Conference have reviewed the use of the HF bands by
the aeronautical mobile (R) and maritime mobile services with a view to protecting
operational, distress and safety communications;
k) that this Resolution identifies several interference mitigation techniques that
can be employed by administrations on a non-mandatory basis,
considering in particular
a) that it is of paramount importance that the distress and safety channels of the
maritime mobile service be kept free from harmful interference, since they are essential
for the protection of the safety of life and property;
b) that it is also of paramount importance that channels directly concerned with
the safe and regular conduct of aircraft operations be kept free from harmful
interference, since they are essential for the safety of life and property,
resolves to invite ITU-R and ITU-D, as appropriate
to increase regional awareness of appropriate practices in order to help mitigate
interference in the HF bands, especially on distress and safety channels,
invites administrations
1 to ensure that stations of services other than the maritime mobile service
abstain from using frequencies in distress and safety channels and their guardbands and
in the bands allocated exclusively to that service, except under the conditions expressly
specified in Nos. 4.4, 5.128, 5.129*, 5.137 and 4.13 to 4.15; and to ensure that stations
of services other than the aeronautical mobile (R) service abstain from using
frequencies allocated to that service except under the conditions expressly specified in
Nos. 4.4 and 4.13;
2 to make every effort to identify and locate the source of any unauthorized
emission capable of endangering human life or property and the safe and regular
conduct of aircraft operations, and to communicate their findings to the
Radiocommunication Bureau;
3 to participate, in accordance with item 4 in the Annex, in any monitoring
programmes organized by the Bureau or administrations, if so agreed among those
administrations, without adversely affecting the rights of other administrations or
conflicting with any provisions of the Radio Regulations;
_______________
* Note by the Secretariat: WRC-07 suppressed provision No. 5.129 and modified provision
No. 5.128 by merging the contents of former provisions Nos. 5.128 and 5.129.
Part B – SECTION III – RES207 243
4 to make every effort to prevent unauthorized transmissions in bands allocated
to the maritime mobile service and the aeronautical mobile (R) service;
5 to request their competent authorities to take, within their respective
jurisdiction, such legislative or regulatory measures which they consider necessary or
appropriate in order to prevent stations from unauthorized use of distress and safety
channels or from operating in contravention of No. 23.2;
6 to take all necessary steps in such cases of contravention of No. 23.2 to ensure
the cessation of any transmissions contravening the provisions of the Radio Regulations
on the frequencies or in the bands referred to in this Resolution;
7 to employ as many of the interference mitigation techniques referred to in the
Annex as are appropriate for the maritime mobile and aeronautical mobile (R) services,
instructs the Radiocommunication Bureau
1 to seek the cooperation of administrations in identifying the sources of those
emissions by all available means and in securing the cessation of those emissions;
2 when the station of another service transmitting in a band allocated to the
maritime mobile service or to the aeronautical mobile (R) service has been identified, to
inform the administration concerned;
3 to include the problem of interference to maritime and aeronautical distress
and safety channels on the agenda of relevant regional radiocommunication seminars,
instructs the Secretary-General
to bring this Resolution to the attention of the International Maritime Organization and
the International Civil Aviation Organization for such actions as they may consider
appropriate.
ANNEX TO RESOLUTION 207 (Rev.WRC-03)
Interference mitigation techniques
This Annex lists several possible HF interference mitigation techniques that may be
used, either in combination or singly, depending on the resources of administrations.
Use of any or all of these techniques is not mandatory.
244 Maritime Manual
1 Alternative modulation methods
The use of digitally modulated emissions, such as QPSK, to replace or supplement
analogue SSB voice (J3E) and data (J2B) emissions. This initiative would need to be
adopted internationally to allow the interoperability of equipment. For example, ICAO
has adopted an HF data-link standard to provide packet data communications using
automated link establishment and adaptive frequency control techniques as a
supplement to analogue SSB voice communications (see ICAO Convention, Annex 10).
2 Passive and active/adaptive antenna systems
Use of passive and active/adaptive antenna systems to reject unwanted signals.
3 Channel barring
Administrations should ensure through their licensing, equipment standardization and
inspection arrangements that, in compliance with No. 43.1, HF radio equipment cannot
transmit on frequencies exclusively allocated to the aeronautical mobile (R) service, as
detailed in Appendix 27, except for frequencies allocated for worldwide use and shared
with the aeronautical mobile (OR) service (see Appendix 26/3.4).
4 Regional HF monitoring and direction-finding facilities
Collaboration and cooperation between regional administrations to coordinate the use
of monitoring and direction-finding facilities.
5 Transmission of warning messages
Transmission of multilanguage warning messages on specific channels affected by
strong or persistent interference. Such transmissions should be conducted after
coordination with the users of the affected services and the administration(s) or
competent authorities concerned.
6 Education and publicity initiatives
Administrations should provide education and publicity initiatives on the proper use of
the radio-frequency spectrum in these bands.
Part B – SECTION III – RES331 245
RESOLUTION 331 (Rev.WRC-07)
Transition to the Global Maritime Distress and Safety System
(GMDSS)
The World Radiocommunication Conference (Geneva, 2007),
noting
that all ships subject to the International Convention for the Safety of Life at Sea
(SOLAS), 1974, as amended, are required to be fitted for the Global Maritime Distress
and Safety System (GMDSS),
noting further
a) that a number of administrations have taken steps to implement the GMDSS
also for classes of vessels not subject to SOLAS, 1974, as amended;
b) that an increasing number of vessels not subject to SOLAS, 1974, as amended,
are making use of the techniques and frequencies of the GMDSS prescribed in
Chapter VII;
c) that this Conference has amended Chapter VII to provide for maintaining
interoperability between ships fitted for GMDSS and ships not yet fully equipped for
GMDSS;
d) that there may be a need to maintain existing shore-based distress and safety
services for the reception of distress, urgency and safety calling by voice on VHF
channel 16 so that vessels not subject to SOLAS, 1974, as amended and not yet using
the techniques and frequencies of the GMDSS will be able to attract attention and
obtain assistance from these services;
e) that the International Maritime Organization (IMO) is of the view that SOLAS
ships, while at sea, should be required to keep a listening watch on VHF channel 16, for
the foreseeable future, with a view to providing:
– a distress alerting and communication channel for non-SOLAS ships; and
– bridge-to-bridge communications;
f ) that IMO has urged administrations to require all seagoing vessels under
national legislation, and encourage all vessels voluntarily carrying VHF radio
equipment to be fitted with facilities for transmitting and receiving distress alerts by
digital selective calling (DSC) on VHF channel 70;
g) that the Radio Regulations require GMDSS ships to keep watch on the
appropriate DSC distress frequencies;
246 Maritime Manual
h) that separate provisions in the existing Radio Regulations designate VHF
channel 16 as the international channel for general calling by radiotelephony;
i) that several administrations have established Vessel Traffic Service (VTS)
systems and require their vessels to keep watch on local VTS channels;
j) that ships that are required by SOLAS to carry a radio station have been
equipped with DSC, and many vessels subject to national carriage requirements are also
being equipped with DSC, but the majority of vessels that carry a radio station on a
voluntary basis might not yet have DSC equipment;
k) that similarly, many administrations have established distress and safety
service based on DSC watchkeeping, but the majority of port stations, pilot stations and
other operational coast stations might not yet have been equipped with DSC facilities;
l) that Nos 52.190 to 52.192 and 52.232 to 52.234 allow frequency 2 182 kHz
and channel 16 to be used for call and reply,
recognizing
a) that, as indicated in noting further a), b), f), j) and k) above, stations in the
maritime mobile service are increasingly making use of the frequencies and techniques
of GMDSS;
b) that this Conference has adopted provisions for distress, urgency and safety
calling by radiotelephony on VHF channel 16, requiring ships, where practicable, to
maintain watch on VHF channel 16;
c) the need to maintain existing shore-based distress and safety services for
reception of distress, urgency and safety calling by voice on VHF channel 16 for some
years after this Conference so that vessels not subject to SOLAS, 1974, as amended,
and not yet using the techniques and frequencies of the GMDSS, will be able to attract
attention and obtain assistance from these services until such time as they are able to
participate in the GMDSS;
d) the need indicated in noting further d) above for maintaining existing shore-
based distress, urgency and safety services on VHF channel 16,
resolves
1 to retain the provisions permitting use of VHF channel 16 and the frequency
2 182 kHz for general voice-calling;
2 to urge all administrations to assist in enhancing safety at sea by:
– encouraging all vessels to finalize the transition to the GMDSS as soon as
possible;
Part B – SECTION III – RES331 247
– encouraging, where appropriate, establishment of suitable shore-based
facilities for GMDSS, either on an individual basis or in cooperation with
other relevant parties in the area;
– encouraging all vessels carrying maritime VHF equipment to be fitted with
DSC on VHF channel 70 as soon as possible, taking into account the relevant
decisions of IMO;
– encouraging vessels to limit their use of VHF channel 16 and the frequency
2 182 kHz for calling to the minimum necessary, noting the provisions of
No. 52.239;
3 that coast stations forming part of shore-based arrangements in the area
concerned for reception of distress calling by radiotelephony on VHF channel 16
should maintain an efficient watch on VHF channel 16. Such watch should be indicated
in the List of Coast Stations and Special Service Stations;
4 that administrations may release their ship stations and coast stations from the
listening watch on VHF channel 16 in respect of distress, urgency and safety calling by
voice, in accordance with relevant decisions of IMO and ITU on aural watch-keeping
requirements on channel 16, taking into account the GMDSS radio systems available in
the area concerned;
when doing so, administrations should:
– inform IMO of their decisions and submit to IMO details on the area
concerned;
– inform the Secretary-General of the necessary details for inclusion in the List
of Coast Stations and Special Service Stations,
resolves further
that the Secretary-General should ensure that such arrangements and details regarding
the area concerned be indicated in relevant maritime publications,
invites ITU-R
to monitor the development of and changes to the GMDSS, in particular:
– watch-keeping requirements;
– distress alerting;
– carriage requirements,
and report to a future world radiocommunication conference on when further
rationalization of Chapter VII should be considered,
248 Maritime Manual
instructs the Secretary-General
to bring this Resolution to the attention of IMO, the International Civil Aviation
Organization (ICAO) and the International Association of Marine Aids to Navigation
and Lighthouse Authorities (IALA).
Part B – SECTION III – RES339 249
RESOLUTION 339 (Rev.WRC-07)
Coordination of NAVTEX services
The World Radiocommunication Conference (Geneva, 2007),
considering
a) that the International Maritime Organization (IMO) has established a
Coordinating Panel on NAVTEX to, inter alia, coordinate the operational aspects of
NAVTEX services, such as allocation of transmitter identification character (B1) and
time schedules, in the planning stages for transmissions on the frequencies 490 kHz,
518 kHz or 4 209.5 kHz;
b) that coordination in the frequencies 490 kHz, 518 kHz and 4 209.5 kHz is
essentially operational;
c) that the frequency band around 518 kHz is also allocated to the aeronautical
radionavigation service on a primary basis,
resolves
to invite administrations to apply the procedures established by IMO, taking into
account the IMO NAVTEX Manual, for coordinating the use of the frequencies
490 kHz, 518 kHz and 4 209.5 kHz,
instructs the Secretary-General
to invite IMO to provide ITU with information on a regular basis on operational
coordination for NAVTEX services on the frequencies 490 kHz, 518 kHz and
4 209.5 kHz,
instructs the Director of the Radiocommunication Bureau
to publish this information in the List of Coast Stations and Special Service Stations
(List IV) (see No. 20.7).
250 Maritime Manual
RESOLUTION 342 (Rev.WRC-2000)
New technologies to provide improved efficiency in the use of the
band 156-174 MHz by stations in the maritime mobile service
The World Radiocommunication Conference (Istanbul, 2000),
considering
a) that the agenda of this Conference included the consideration of the use of new
technologies for the maritime mobile service in the band 156-174 MHz and the
consequential revision of Appendix 18;
b) Recommendation 318 (Mob-87)*, particularly noting b) and c) thereof;
c) that Appendix 18 identifies frequencies to be used for distress and safety
communications on an international basis;
d) that the introduction of new technology in the maritime mobile service shall
not disrupt distress and safety communications in the VHF band including those
established by the International Convention for the Safety of Life at Sea (SOLAS),
1974, as amended;
e) that the date for full implementation of the global maritime distress and safety
system (GMDSS) was 1 February 1999;
f) that ITU-R is conducting studies on improving efficiency in the use of this
band, and that these studies are still ongoing;
g) that changes made in Appendix 18 should not prejudice the future use of these
frequencies or the capabilities of systems or new applications required for use by the
maritime mobile service;
h) that the congestion on Appendix 18 frequencies calls for the implementation of
efficient new technologies;
i) that the use of new technology on maritime VHF frequencies will make it
possible to better respond to the emerging demand for new services;
j) that ITU-R has approved Recommendation ITU-R M.1312 relating to a long-
term solution for improved efficiency in the use of the band 156-174 MHz by stations
in the maritime mobile service;
_______________
* Note by the Secretariat: This Recommendation was abrogated by WRC-07.
Part B – SECTION III – RES342 251
k) that ITU-R has approved Recommendation ITU-R M.1371 relating to
technical characteristics for a universal shipborne automatic identification system using
time-division multiple access in the VHF maritime mobile band;
l) that there is a need to maintain some duplex channels for specific applications,
noting
a) that the global maritime market may not be of a sufficient size to warrant the
development of a new system solely for the maritime service;
b) that digital systems have been successfully implemented in the land mobile
service,
noting also
that this Conference has modified Appendix 18, including the addition of note o), to
permit the possible use on a voluntary basis of various channels or bands created by the
conversion of some duplex channels to simplex channels, for the initial testing and the
possible future introduction of new technologies,
resolves
1 that, in order to provide full worldwide interoperability of equipment on ships,
there should be one technology, or more than one interoperable worldwide technology,
implemented under Appendix 18;
2 that, as soon as the ITU-R studies are complete, a future competent conference
should consider any necessary changes to Appendix 18 to enable the use of new
technologies by the maritime mobile service,
invites ITU-R
to finalize the following studies:
a) identify the future requirements of the maritime mobile service;
b) identify suitable technical characteristics of the system or interoperable
systems to replace existing technology;
c) identify necessary modifications to the Table of frequencies contained in
Appendix 18;
d) recommend a transition plan for the introduction of new technologies;
e) recommend how new technologies can be introduced while ensuring
compliance with the distress and safety requirements,
252 Maritime Manual
instructs the Secretary-General
to communicate this Resolution to the International Maritime Organization and the
International Association of Lighthouse Authorities.
Part B – SECTION III – RES343 253
RESOLUTION 343 (WRC-97)
Maritime certification for personnel of ship stations and ship earth
stations for which a radio installation is not compulsory
The World Radiocommunication Conference (Geneva, 1997),
considering
a) that WRC-97 has considered the question of certification for personnel of ship
stations and ship earth stations within the Global Maritime Distress and Safety System
(GMDSS);
b) that GMDSS will be fully implemented on 1 February 1999 by ships subject to
an international agreement;
c) that ships not subject to an international agreement have begun to adopt
GMDSS systems and techniques;
d) that use of GMDSS equipment should be accompanied by appropriate training
and certification;
e) that the Radio Regulations stipulate that the service of every ship radio station
working on frequencies assigned for international use shall be performed by operators
holding a certificate;
f) that the present certificates described in Article 47 may be too demanding for
radio operators of ship stations and ship earth stations on board ships for which a radio
installation is not compulsory,
noting
that a number of administrations currently issue radio operator certificates specially
designed for the non-compulsory sector,
resolves
that administrations wishing to implement special certification for the non-compulsory
sector should implement the certificates contained in the Annex to this Resolution,
invites ITU-R
to develop a Recommendation describing these certificates,
254 Maritime Manual
instructs the Secretary-General
to bring this Resolution to the attention of the International Maritime Organization
(IMO).
ANNEX TO RESOLUTION 343 (WRC-97)
Examination syllabus for radio operator’s certificates appropriate to
vessels using the frequencies and techniques of the Global Maritime
Distress and Safety System on a non-compulsory basis
Introduction
The introduction of the Global Maritime Distress and Safety System (GMDSS) in
February 1992 made it necessary to harmonize the examination requirements for
certificates for professional radio operators. Harmonized examination procedures for
the general operator’s Certificate and restricted operator’s Certificate, based on the
syllabuses described in Article 47, have already been introduced for maritime radio
operators performing radiocommunication duties on board vessels subject to the
International Convention for the Safety of Life at Sea (SOLAS), 1974, as amended. The
GMDSS will be fully implemented on 1 February 1999 for vessels subject to SOLAS,
1974, as amended.
For vessels not subject to SOLAS, 1974, as amended, and which install radiocom-
munication equipment on a voluntary basis, there are significant advantages to also
using the GMDSS. However, it was foreseen by some administrations that such vessels
would use some, but not all, of the frequencies and techniques of the GMDSS and that
radio personnel on board such vessels would not need the same level of certification as
radio personnel on board vessels which use all of the frequencies and techniques of the
GMDSS on a compulsory basis. A syllabus has been developed which provides the
flexibility for a depth of study, level of knowledge, and length of course appropriate to
meet the certification requirements of radio personnel on board vessels which use some
of the frequencies and techniques of the GMDSS on a non-compulsory basis. The
syllabus also provides for certification in the use of satellite equipment where
appropriate.
This Annex describes the syllabus developed to meet the certification requirements
referred to above, and which are implemented in a number of countries under the title
“Long Range Certificate” and “Short Range Certificate”. The Short Range Certificate
should at least contain those elements of the syllabus which are relevant to sea area A1.
Part B – SECTION III – RES343 255
Examination syllabus
The examination should consist of theoretical and practical tests and should include at
least:
A General knowledge of radiocommunications in the maritime mobile
service
A.1 The general principles and basic features of the maritime mobile service.
B Detailed practical knowledge and ability to use radio equipment
B.1 The VHF radio installation. Use of VHF equipment in practice.
B.2 The MF/HF radio installation. Use of MF/HF equipment in practice.
B.3 Purpose and use of digital selective calling facilities and techniques.
C Operational procedures of the GMDSS and detailed practical operation of
GMDSS subsystems and equipment
C.1 Basic introduction to GMDSS procedures.
C.2 Distress, urgency and safety communication procedures in the GMDSS.
C.3 Distress, urgency and safety communication procedures by radiotelephony in
the old distress and safety system.
C.4 Protection of distress frequencies.
C.5 Maritime safety information (MSI) systems in the GMDSS.
C.6 Alerting and locating signals in the GMDSS.
D Operational procedures and regulations for radiotelephone communi-
cations
D.1 Ability to exchange communications relevant to the safety of life at sea.
D.2 Regulations, obligatory procedures and practices.
D.3 Practical and theoretical knowledge of radiotelephone procedures.
D.4 Use of the international phonetic alphabet and, where appropriate, parts of the
IMO Standard Marine Communication Phrases.
E Optional examination module for the maritime mobile-satellite service for
vessels not subject to a compulsory fit
E.1 The general principles and basic features of the maritime mobile-satellite
service.
E.2 Operational procedures and detailed practical operation of ship earth stations
in the GMDSS.
256 Maritime Manual
RESOLUTION 344 (Rev.WRC-03)
Management of the maritime mobile service identity
numbering resource
The World Radiocommunication Conference (Geneva, 2003),
noting
a) that the installation of digital selective calling equipment or Inmarsat B, C
or M ship earth station equipment on ships participating in the Global Maritime Distress
and Safety System (GMDSS) on a mandatory or voluntary basis requires the
assignment of a unique nine-digit maritime mobile service identity (MMSI);
b) that such equipment offers the possibility to connect with public
telecommunication networks;
c) that only mobile-satellite systems have been able to resolve the various billing,
routeing, charging and signalling requirements needed to provide full two-way
automatic connectivity between ships and the international public correspondence
service;
d) that ships using the present generation of mobile-satellite ship earth stations
have to be assigned an MMSI ending with three trailing zeros in order to support
automatic access to public telecommunication networks through a diallable ship
telephone number whose format is compliant with ITU-T Recommendation E.164 but
can only accommodate the first six digits of the MMSI;
e) that the first three digits of a ship station MMSI form the maritime
identification digits (MID), which denote the ship’s administration or geographical area
of origin;
f) that each MID only has sufficient capacity to identify 999 ships using the
three-trailing-zero number format, with the result that widespread use of MMSIs with
three trailing zeros will rapidly exhaust the capacity of each MID,
considering
a) that digital selective calling distress alerts require valid identities recognizable
by search and rescue authorities in order to ensure a timely response;
b) that Recommendation ITU-R M.585 contains guidance for the assignment of
MMSIs,
Part B – SECTION III – RES344 257
recognizing
a) that even domestic ships which install the present generation of ship earth
stations operating to Inmarsat B, C or M standards will require the assignment of MMSI
numbers from those numbers originally intended for ships communicating worldwide,
further depleting the resource;
b) that future growth of Inmarsat B, C or M ship earth station use by
non-compulsory ships may further deplete the MMSI and MID resources;
c) that future generations of mobile-satellite systems offering access to public
telecommunication networks and participating in the GMDSS will employ a free-form
numbering system that need not include any part of the MMSI,
noting further
a) that ITU-T has recommended that ITU-R assume sole responsibility for
managing the MMSI and MID numbering resources;
b) that ITU-R can monitor the status of the MMSI resource, through regular
reviews of the spare capacity available within the MIDs already in use, and the
availability of spare MIDs, taking account of regional variations,
resolves to instruct the Director of the Radiocommunication Bureau
1 to manage the allotment and distribution of the MID resource within the
MMSI numbering format, taking into account:
– Sections II, V and VI of Article 19;
– regional variations in MMSI use;
– spare capacity within the MID resource; and
– the guidelines on MID and MMSI management contained in the most recent
version of Recommendation ITU-R M.585, in particular as regards the reuse of
MMSIs;
2 to report to each world radiocommunication conference on the use and status
of the MMSI resource, noting in particular the anticipated reserve capacity and any
indications of rapid exhaustion of the resource,
258 Maritime Manual
invites ITU-R
to keep under review the Recommendations for assigning MMSIs, with a view to:
– improving the management of the MID and MMSI resources; and
– identifying alternative resources if there is an indication of rapid exhaustion of
these resources,
instructs the Secretary-General
to communicate this Resolution to the International Maritime Organization.
Part B – SECTION III – RES345 259
RESOLUTION 345 (WRC-97)
Operation of Global Maritime Distress and Safety System
equipment on and assignment of maritime mobile service
identities to non-compulsory fitted vessels
The World Radiocommunication Conference (Geneva, 1997),
noting
a) that ships not required by international agreement to carry Global Maritime
Distress and Safety System (GMDSS) equipment could elect to do so for safety
purposes;
b) that such vessels may only carry VHF digital selective calling (DSC)
equipment;
c) that some administrations may not require operators on such vessels to have
appropriate training, certification or licence;
d) that not all administrations assign and register identities to users of VHF DSC
equipment on such ships,
considering
that VHF DSC false distress alerts are a problem for rescue coordination centres,
particularly when incorrect identities are used, or when the radio is operated by persons
untrained in its use,
recognizing
that administrations have different training requirements for users of VHF DSC
equipment,
resolves
1 to invite ITU-R to consider DSC standards and operating procedures in order
to simplify operation of this equipment;
2 to invite ITU-T and ITU-R to review the process for assigning maritime
mobile service identities for simplifying the process, taking into account cases of new
installation, sale of the vessel or transfer of the equipment to a new ship;
260 Maritime Manual
3 to invite ITU-T and ITU-R to undertake studies to ensure the registration and
continuous accessibility and availability of identities to rescue authorities,
instructs the Secretary-General
to communicate this Resolution to the International Maritime Organization for
consideration and comments.
Part B – SECTION III – RES349 261
RESOLUTION 349 (WRC-97)
Operational procedures for cancelling false distress alerts in the
Global Maritime Distress and Safety System
The World Radiocommunication Conference (Geneva, 1997),
considering
a) that the 1974 International Convention for the Safety of Life at Sea (SOLAS),
as amended, prescribes that ships subject to that Convention shall be fitted with Global
Maritime Distress and Safety System (GMDSS) equipment as appropriate;
b) that non-SOLAS vessels are also being equipped with GMDSS equipment;
c) that the transmission and relay of false distress alerts is a significant problem
within the GMDSS,
noting
that the International Maritime Organization (IMO) has developed similar operational
procedures to cancel false distress alerts,
resolves
1 to urge administrations to take all necessary measures to avoid false distress
alerts and to minimize the unnecessary burden on rescue organizations which occurs;
2 to urge administrations to encourage the correct use of GMDSS equipment,
with particular attention to appropriate training;
3 to urge administrations to implement the operational procedures contained in
the Annex to this Resolution;
4 that administrations should take any consequential appropriate action in this
respect,
instructs the Secretary-General
to bring this Resolution to the attention of IMO.
262 Maritime Manual
ANNEX TO RESOLUTION 349 (WRC-97)
Cancelling of false distress alerts
If a distress alert is inadvertently transmitted, the following steps shall be taken to
cancel the distress alert.
1 VHF digital selective calling
1) Reset the equipment immediately;
2) Set to channel 16; and
3) Transmit a broadcast message to “All Stations” giving the ship’s name, call
sign and maritime mobile service identity (MMSI), and cancel the false
distress alert.
2 MF digital selective calling
1) Reset the equipment immediately;
2) Tune for radiotelephony transmission on 2 182 kHz; and
3) Transmit a broadcast message to “All Stations” giving the ship’s name, call
sign and MMSI, and cancel the false alert.
3 HF digital selective calling
1) Reset the equipment immediately;
2) Tune for radiotelephony on the distress and safety frequency in each band in
which a false distress alert was transmitted (see Appendix 15); and
3) Transmit a broadcast message to “All Stations” giving the ship’s name, call
sign and MMSI, and cancel the false alert on the distress and safety frequency
in each band in which the false distress alert was transmitted.
4 Inmarsat ship earth station
Notify the appropriate rescue coordination centre that the alert is cancelled by sending a
distress priority message by way of the same coast earth station through which the false
distress alert was sent. Provide ship name, call sign and Inmarsat identity with the
cancelled alert message.
Part B – SECTION III – RES349 263
5 Emergency position indicating radiobeacon (EPIRB)
If for any reason an EPIRB is activated inadvertently, contact the appropriate rescue
coordination centre through a coast station or land earth station and cancel the distress
alert.
6 General
Notwithstanding the above, ships may use additional appropriate means available to
them to inform the appropriate authorities that a false distress alert has been transmitted
and should be cancelled.
264 Maritime Manual
RESOLUTION 352 (WRC-03)
Use of the carrier frequencies 12290 kHz and 16420 kHz for
safety-related calling to and from rescue coordination centres
The World Radiocommunication Conference (Geneva, 2003),
considering
a) that this Conference modified No. 52.221A to allow safety-related calling to
and from rescue coordination centres on the carrier frequencies 12 290 kHz and
16 420 kHz;
b) that this limited safety-related calling function on these carrier frequencies will
enhance the capability of those search and rescue organizations which maintain watch
on these distress and safety frequencies to call vessels not utilizing the Global Maritime
Distress and Safety System (GMDSS),
noting
a) that regulation IV/4.8 of the International Convention for the Safety of Life at
Sea (SOLAS), 1974, as amended, requires that SOLAS ships, while at sea, be capable
of transmitting and receiving general radiocommunications to and from shore-based
radio systems or networks;
b) that general communications may include safety-related communications
necessary for the safe operation of vessels,
further noting
that safety-related communications require adequate, effective and immediate access
and protection,
recognizing
a) that the International Maritime Organization (IMO) notes that distress,
urgency and safety radiocommunications include, but are not limited to:
– transmissions of maritime safety information;
– distress calls and traffic;
– acknowledgment and relaying of distress calls;
– search and rescue coordination communications;
– ship movement service communications;
Part B – SECTION III – RES352 265
– communications related to the safe operation of ships;
– communications related to navigation;
– meteorological warnings;
– meteorological observations;
– ship position reports; and
– medical emergencies (e.g. MEDICO/MEDIVAC);
b) that distress, urgency and safety communications are defined in Articles 32
and 33,
resolves
1 that the carrier frequencies 12 290 kHz and 16 420 kHz be used only for
distress, urgency and safety communications, and safety-related calling limited to that
to and from rescue coordination centres;
2 that safety-related calling be initiated only after determination that other
communications are not present on these frequencies;
3 that safety-related calling be minimized and not cause interference to distress,
urgency and safety communications,
invites administrations
to encourage the coast and ship stations under their jurisdiction to use digital selective
calling techniques,
instructs the Secretary-General
to bring this Resolution to the attention of the IMO.
266 Maritime Manual
RESOLUTION 354 (WRC-07)
Distress and safety radiotelephony procedures for 2 182 kHz
The World Radiocommunication Conference (Geneva, 2007),
noting
a) that all ships subject to the International Convention for the Safety of Life at
Sea (SOLAS), 1974, as amended, are required to be fitted for the Global Maritime
Distress and Safety System (GMDSS);
b) that some vessels not subject to SOLAS, 1974, as amended, may not be
making use of the techniques and frequencies of GMDSS prescribed in Chapter VII and
may wish to continue using radiotelephony procedures for distress and safety
communications on 2 182 kHz until such time as they are able to participate in the
GMDSS;
c) that some administrations may have a need to maintain shore-based
radiotelephony distress and safety services on 2 182 kHz so that vessels not subject to
SOLAS, 1974, as amended, and not yet using the techniques and frequencies of
GMDSS will be able to obtain assistance from these services until such time as they are
able to participate in GMDSS,
considering
that there needs to be some recognized guidance for the use of radiotelephony on
2 182 kHz for distress and safety communications,
resolves
1 that ships, when in distress or when engaged in urgency or safety-related
communications on 2 182 kHz, use the radiotelephony procedures contained in the
Annex to this Resolution;
2 that coast stations, in order to maintain communication with non-GMDSS
ships that are in distress or engaged in urgency or safety related communications on
2 182 kHz, use the radiotelephony procedures contained in the Annex to this
Resolution.
Part B – SECTION III – RES354 267
ANNEX TO RESOLUTION 354 (WRC-07)
Distress and safety radiotelephony procedures for 2 182 kHz*
PART A1 – GENERAL
§ 1 The frequencies and techniques specified in this Resolution may be used in the
maritime mobile service for stations1 not required by national or international regulation
to fit GMDSS equipment and for communications between those stations and aircraft.
However, stations of the maritime mobile service, when additionally fitted with any of
the equipment used by stations operating in conformity with the provisions specified in
Chapter VII, should, when using that equipment, comply with the appropriate
provisions of that Chapter.
§ 2 1) No provision of this Resolution prevents the use by a mobile station or
mobile earth station in distress of any means at its disposal to attract attention, make
known its position, and obtain help.
2) No provision of this Resolution prevents the use by stations on board
aircraft or ships engaged in search and rescue operations, in exceptional circumstances,
of any means at their disposal to assist a mobile station or mobile earth station in
distress.
3) No provision of this Resolution prevents the use by a land station or coast
earth station, in exceptional circumstances, of any means at its disposal to assist a
mobile station or mobile earth station in distress (see also No. 4.16).
§ 3 In cases of distress, urgency or safety, communications by radiotelephony
should be made slowly and distinctly, each word being clearly pronounced to facilitate
transcription.
§ 4 The abbreviations and signals of Recommendation ITU-R M.1172 and the
Phonetic Alphabet and Figure Code in Appendix 14 should be used where applicable2.
_______________
* Distress and safety communications include distress, urgency and safety calls and messages.
1 These stations may include rescue coordination centres. The term “Rescue Coordination
Centre” as defined in the International Convention on Maritime Search and Rescue (1979) refers
to a unit responsible for promoting the efficient organization of search and rescue services and
for coordinating the conduct of search and rescue operations within a search and rescue region.
2 The use of the Standard Marine Communication Phrases and, where language difficulties
exist, the International Code of Signals, both published by the International Maritime
Organization, is also recommended.
268 Maritime Manual
§ 5 Distress, urgency and safety communications may also be made using digital
selective calling and satellite techniques and/or direct-printing telegraphy, in
accordance with the provisions specified in Chapter VII and relevant ITU-R
Recommendations.
§ 6 Mobile stations3 of the maritime mobile service may communicate for safety
purposes with stations of the aeronautical mobile service. Such communications shall
normally be made on the frequencies authorized, and under the conditions specified, in
Section I of Part A2 (see also § 2 1)).
§ 7 Mobile stations of the aeronautical mobile service may communicate for
distress and safety purposes with stations of the maritime mobile service in conformity
with the provisions of this Resolution.
§ 8 Any aircraft required by national or international regulations to communicate
for distress, urgency or safety purposes with stations of the maritime mobile service
shall be capable of transmitting and receiving class J3E emissions when using the
carrier frequency 2 182 kHz or the carrier frequency 4 125 kHz.
PART A2 – FREQUENCIES FOR DISTRESS AND SAFETY
Section I – Availability of frequencies
A – 2182 kHz
§ 1 1) The carrier frequency 2 182 kHz is an international distress frequency for
radiotelephony; it may be used by ship, aircraft and survival craft stations when
requesting assistance from the maritime services. It is used for distress calls and distress
traffic, for the urgency signal and urgency messages and for the safety signal. Safety
messages should be transmitted, when practicable, on a working frequency, after a
preliminary announcement on 2 182 kHz. The class of emission to be used for
radiotelephony on the frequency 2 182 kHz shall be J3E. Distress traffic on 2 182 kHz
following the reception of a distress call using digital selective calling should take into
account that some shipping in the vicinity may not be able to receive this traffic.
2) If a distress message on the carrier frequency 2 182 kHz has not been
acknowledged, the distress call and message may be transmitted again on a carrier
frequency of 4 125 kHz or 6 215 kHz, as appropriate.
_______________
3 Mobile stations communicating with the stations of the aeronautical mobile (R) service in
bands allocated to the aeronautical mobile (R) service shall conform to the provisions of the
Regulations which relate to that service and, as appropriate, any special arrangements between
the governments concerned by which the aeronautical mobile (R) service is regulated.
Part B – SECTION III – RES354 269
3) However, ship stations and aircraft which cannot transmit either on the
carrier frequency 2 182 kHz or on the carrier frequencies 4 125 kHz or 6 215 kHz may
use any other available frequency on which attention might be attracted.
4) Coast stations using the carrier frequency 2 182 kHz for distress purposes
and to send navigational warnings may transmit an audible alarm signal4 of short
duration for the purpose of attracting attention to the message which follows.
B – 4125 kHz
§ 2 1) The carrier frequency 4 125 kHz is used to supplement the carrier
frequency 2 182 kHz for distress and safety purposes and for call and reply. This
frequency is also used for distress and safety traffic by radiotelephony.
2) The carrier frequency 4 125 kHz may be used by aircraft to communicate
with stations of the maritime mobile service for distress and safety purposes, including
search and rescue.
C – 6215 kHz
§ 3 The carrier frequency 6 215 kHz is used to supplement the carrier frequency
2 182 kHz for distress and safety purposes and for call and reply. This frequency is also
used for distress and safety traffic by radiotelephony.
Section II – Protection of distress and safety frequencies
A – General
§ 4 Test transmissions on any of the distress and safety frequencies described
above shall be kept to a minimum and, wherever practicable, be carried out on artificial
antennas or with reduced power.
§ 5 Before transmitting on any of the frequencies identified for distress and safety
communications, a station shall listen on the frequency concerned to make sure that no
distress transmission is being sent (see Recommendation ITU-R M.1171). This does not
apply to stations in distress.
_______________
4 Alarm signals may consist of transmissions of sinusoidal audio frequency tones 1 300 Hz,
2 200 Hz, or both. Different tone generation patterns may be used to signal the type of message
which follows, and an alarm signal ending in a 10-second continuous tone could be used to
identify a transmission by a coast station.
270 Maritime Manual
B – 2182 kHz
§ 6 1) Except for transmissions authorized on the carrier frequency 2 182 kHz
and on the frequencies 2 174.5 kHz, 2 177 kHz, 2 187.5 kHz and 2 189.5 kHz, all
transmissions on the frequencies between 2 173.5 kHz and 2 190.5 kHz are forbidden
(see also Appendix 15).
2) To facilitate the reception of distress calls, all transmissions on 2 182 kHz
should be kept to a minimum.
Section III – Watch on distress frequencies
A – 2182 kHz
§ 7 1) Coast stations may maintain a watch on the carrier frequency 2 182 kHz if
so directed by their Administration. Such assignments should be indicated in the List of
Coast Stations and Special Service Stations.
2) Ship stations not fitted with equipment compatible with the GMDSS are
encouraged to keep the maximum watch practicable on the carrier frequency 2 182 kHz.
B – 4125 kHz, 6215 kHz
§ 8 Coast stations may maintain additional watch, as permitted, on the carrier
frequencies 4 125 kHz and 6 215 kHz. Such assignments should be indicated in the List
of Coast Stations and Special Service Stations.
PART A3 – DISTRESS COMMUNICATIONS
Section I – General
§ 1 The general provisions for distress communications are found in Section I of
Article 32 (see Nos. 32.1, 32.3, and 32.4).
Section II – Distress signal, call and message
§ 2 The radiotelephone distress signal, call and message are described in Section II
of Article 32 (see Nos. 32.13BA, 32.9, 32.13B, 32.13C, and 32.13D).
Part B – SECTION III – RES354 271
Section III – Procedures
§ 3 After the transmission by radiotelephony of its distress message, the mobile
station may be requested to transmit suitable signals, followed by its call sign or other
identification, to permit direction-finding stations to determine its position. This request
may be repeated at frequent intervals if necessary.
§ 4 1) The distress message, preceded by the distress call, shall be repeated at
intervals until an answer is received.
2) The intervals shall be sufficiently long to allow time for replying stations,
in their preparations, to start their sending apparatus.
§ 5 When the mobile station in distress receives no answer to a distress message
sent on the distress frequency, the message may be repeated on any other available
frequency on which attention might be attracted.
Section IV – Transmission of a distress relay message by a station not itself in
distress
§ 6 The radiotelephone procedures for the transmission of a distress relay message
by a station not itself in distress are found in Section II of Article 32 (see Nos. 32.16 to
32.19A and 32.19D to 32.19F).
Section V – Receipt and acknowledgement of a distress message
§ 7 The procedures relating to the receipt and acknowledgement of a distress
message are found in Section II of Article 32 (see Nos. 32.23, 32.26, 32.28, 32.29,
32.30 and 32.35).
Section VI – Distress traffic
§ 8 The radiotelephone procedures relating to the distress traffic are found in
Section III of Article 32 (see Nos. 32.39 to 32.42, 32.45 to 32.47, 32.49 to 32.52 and
32.54 to 32.59).
§ 9 1) Every mobile station acknowledging receipt of a distress message shall,
on the order of the person responsible for the ship, aircraft or other vehicle, transmit the
following information in the order shown as soon as possible:
– its name;
– its position;
– the speed at which it is proceeding towards, and the approximate time it will
take to reach, the mobile station in distress;
272 Maritime Manual
– additionally, if the position of the ship in distress appears doubtful, ship
stations should also transmit, when available, the true bearing of the ship in
distress.
2) Before transmitting the message specified in § 9 1), the station shall
ensure that it will not interfere with the emissions of other stations better situated to
render immediate assistance to the station in distress.
PART A4 – URGENCY AND SAFETY COMMUNICATIONS
Section I – Urgency communications
§ 1 The radiotelephone procedures for urgency communications are found in
Sections I and II of Article 33 (see Nos. 33.1 to 33.7 and 33.8, 33.8B to 33.9A and
33.11 to 33.16).
Section II – Safety communications
§ 2 The radiotelephone procedures for safety communications are found in
Sections I and IV of Article 33 (see Nos. 33.31, 33.31C, 33.32, 33.34 to 33.35 and
33.38B).
___________
SECTION IV
ITU-R Recommendations incorporated by reference
(Extracts)
Note: In accordance with the decisions of WRC-2000, the editions of the Radio
Regulations (RR) use a new numbering scheme which consists, inter alia, in abolishing
the prefix “S” in front of the provision numbers, Article numbers and Appendix
numbers. However, since the Recommendations included in this Section were not
revised after 1999, the references made to the RR in these Recommendations refer to
the (simplified) Radio Regulations, edition of 1998 (references commencing with “S”)
which were provisionally applicable as from 1 January 1999, or to the former RR,
edition of 1994 (complemented by Volume 4, edition of 1996) (references without “S”).
Part B – SECTION IV – Rec. ITU-R M.489-2 275
RECOMMENDATION ITU-R M.489-2*
TECHNICAL CHARACTERISTICS OF VHF RADIOTELEPHONE
EQUIPMENT OPERATING IN THE MARITIME MOBILE
SERVICE IN CHANNELS SPACED BY 25 kHz
(1974-1978-1995)
Summary
The Recommendation describes the technical characteristics of VHF radiotelephone transmitters
and receivers (or transceivers) used in the maritime mobile service when operating in 25 kHz
channels of Appendix S18 [Appendix 18] of the Radio Regulations (RR). It also contains those
additional characteristics of transceivers required to operate digital selective calling.
The ITU Radiocommunication Assembly,
considering
a) that Resolution No. 308 of the World Administrative Radio Conference (Geneva,
1979) stipulated that:
– all maritime mobile VHF radiotelephone equipment shall conform to 25 kHz standards by
1 January 1983;
b) that RR Appendix S18 [Appendix 18] gives a table of transmitting frequencies which
is based upon the principle of 25 kHz channel separations for the maritime mobile service;
c) that in Opinion 42, the International Electrotechnical Commission (IEC) has been
invited to advise the ITU Radiocommunication Sector of any methods of measurement
applicable to radio equipment used in land mobile services; and that such methods of
measurement may also be suitable for radio equipment used in maritime mobile services;
d) that there is a need to specify the technical characteristics of VHF radiotelephone
equipment operating in the maritime mobile service in channels spaced by 25 kHz,
recommends
1 that the following characteristics should be met by VHF (metric) FM radiotelephone
equipment used for the maritime mobile services operating on the frequencies specified in RR
Appendix S18 [Appendix 18].
_______________
Note by the Secretariat: The references made to the Radio Regulations (RR) in this Recommendation refer
to the RR as revised by the World Radiocommunication Conference 1995. These elements of the RR will
come into force on 1 June 1998. Where applicable, the equivalent references in the current RR are also
provided in square brackets.
276 Maritime Manual
1.1 General characteristics
1.1.1 The class of emission should be F3E/G3E.
1.1.2 The necessary bandwidth should be 16 kHz.
1.1.3 Only phase modulation (frequency modulation with a pre-emphasis characteristic of
6 dB/octave) should be used.
1.1.4 The frequency deviation corresponding to 100% modulation should approach ± 5 kHz
as nearly as practicable. In no event should the frequency deviation exceed ± 5 kHz. Deviation
limiting circuits should be employed such that the maximum frequency deviation attainable
should be independent of the input audio frequency.
1.1.5 Where duplex or semi-duplex systems are in use, the performance of the radio
equipment should continue to comply with all the requirements of this Recommendation.
1.1.6 The equipment should be designed so that frequency changes between assigned
channels can be carried out within 5 s.
1.1.7 Emissions should be vertically polarized at the source.
1.1.8 Stations using digital selective calling shall have the following capabilities:
a) sensing to determine the presence of a signal on 156.525 MHz (channel 70); and
b) automatic prevention of the transmission of a call, except for distress and safety calls, when
the channel is occupied by calls.
1.2 Transmitters
1.2.1 The frequency tolerance for coast station transmitters should not exceed 5 parts in 106,
and that for ship station transmitters should not exceed 10 parts in 106.
1.2.2 Spurious emissions on discrete frequencies, when measured in a non-reactive load
equal to the nominal output impedance of the transmitter, should be in accordance with the
provisions of RR Appendix S3 [Appendix 8].
1.2.3 The carrier power for coast stations should not normally exceed 50 W.
1.2.4 The carrier power for ship station transmitters should not exceed 25 W. Means should
be provided to readily reduce this power to 1 W or less for use at short ranges, except for digital
selective calling equipment operating on 156.525 MHz (channel 70) in which case the power
reduction facility is optional (see also Recommendation ITU-R M.541 recommends 3.7).
1.2.5 The upper limit of the audio-frequency band should not exceed 3 kHz.
1.2.6 The cabinet radiated power should not exceed 25 µW. In some radio environments,
lower values may be required.
Part B – SECTION IV – Rec. ITU-R M.489-2 277
1.3 Receivers
1.3.1 The reference sensitivity should be equal to or less than 2.0 µV, e.m.f., for a given
reference signal-to-noise ratio at the output of the receiver.
1.3.2 The adjacent channel selectivity should be at least 70 dB.
1.3.3 The spurious response rejection ratio should be at least 70 dB.
1.3.4 The radio frequency intermodulation rejection ratio should be at least 65 dB.
1.3.5 The power of any conducted spurious emission, measured at the antenna terminals,
should not exceed 2.0 nW at any discrete frequency. In some radio environments lower values
may be required.
1.3.6 The effective radiated power of any cabinet radiated spurious emission on any
frequency up to 70 MHz should not exceed 10 nW. Above 70 MHz, the spurious emissions
should not exceed 10 nW by more than 6 dB/octave in frequency up to 1 000 MHz. In some
radio environments, lower values may be required;
2 that reference should also be made to Recommendations ITU-R SM.331 and ITU-R
SM.332 and to the relevant IEC publications on methods of measurement.
278 Maritime Manual
RECOMMENDATION ITU-R M.492-6
OPERATIONAL PROCEDURES FOR THE USE OF DIRECT-PRINTING
TELEGRAPH EQUIPMENT IN THE MARITIME MOBILE SERVICE
(Question ITU-R 5/8)
(1974-1978-1982-1986-1990-1992-1995) Rec. ITU-R M.492-6
Summary
The Recommendation provides in Annex 1 operational procedures for the use of direct-printing
telegraph equipment in communication between a ship and a coast station in the selective ARQ-
mode on a fully automated or semi-automated basis and to a number of ship stations or a single
ship in the broadcast FEC-mode. It also specifies interworking between equipments in
accordance with technical characteristics given in Recommendations ITU-R M.476 and
ITU-R M.625. Appendix 1 contains procedures for setting up of calls.
The ITU Radiocommunication Assembly,
considering
a) that narrow-band direct-printing telegraph services are in operation using equipment as
described in Recommendations ITU-R M.476, ITU-R M.625 and ITU-R M.692;
b) that an improved narrow-band direct-printing telegraph system providing automatic
identification and capable of using the 9-digit ship station identity is described in
Recommendation ITU-R M.625;
c) that the operational procedures necessary for such services should be agreed upon;
d) that, as far as possible, these procedures should be similar for all services and for all
frequency bands (different operational procedures may be required in frequency bands other
than the HF and MF bands);
e) that a large number of equipments complying with Recommendation ITU-R M.476
exist;
f) that interworking between equipments in accordance with Recommendations
ITU-R M.476 and ITU-R M.625 is required, at least for a transitionary period,
recommends
1 that the operational procedures given in Annex 1 be observed for the use of narrow-
band direct-printing telegraph equipment in accordance with either Recommendation
ITU-R M.476 or ITU-R M.625 in the MF and HF bands of the maritime mobile service;
2 that when using direct-printing telegraphy or similar systems in any of the frequency
bands allocated to the maritime mobile service, the call may, by prior arrangement, be made on a
working frequency available for such systems.
Part B – SECTION IV – Rec. ITU-R M.492-6 279
ANNEX 1
Operational procedures
1 Mode A (ARQ)
1.1 Methods used for setting up narrow-band direct-printing telegraph communications
between a ship station and a coast station in the ARQ-mode should be on a fully automatic or
semi-automatic basis, insofar that a ship station should have direct access to a coast station on a
coast station receiving frequency and a coast station should have direct access to a ship station
on a coast station transmitting frequency.
1.2 However, where necessary, prior contact by Morse telegraphy, radiotelephony or other
means is not precluded.
1.3 Through connection to a remote teleprinter station over a dedicated circuit or to a
subscriber of the international telex network may be achieved by manual, semi-automatic or
automatic means.
NOTE 1 – Before an international automatic service can be introduced, agreement has to be
reached on a numbering plan, traffic routing and charging. This should be considered by both
the ITU-T and the ITU-R.
NOTE 2 – Recommendations ITU-R M.476 (see § 3.1.5) and ITU-R M.625 (see § 3.8) make
provision for automatic re-establishment of radio circuits by rephasing in the event of
interruption. However, it has been reported that this procedure has, in some countries, resulted in
technical and operational problems when radio circuits are extended into the public switched
network or to certain types of automated switching or store-and-forward equipments. For this
reason, some coast stations do not accept messages if the rephasing procedure is used.
NOTE 3 – When a connection is set up in the ARQ mode with the international telex network
via a coast station, where practicable the general requirements specified in ITU-T
Recommendation U.63 should be met.
1.4 When, by prior arrangement, unattended operation is required for communication from
a coast station to a ship station, or between two ship stations, the receiving ship station should
have a receiver tuned to the other station’s transmitting frequency and a transmitter tuned or a
transmitter capable of being tuned automatically to the appropriate frequency and ready to
transmit on this frequency.
1.5 For unattended operation a ship station should be called selectively by the initiating
coast or ship station as provided for by Recommendations ITU-R M.476 and ITU-R M.625. The
ship station concerned could have available traffic stored ready for automatic transmission on
demand of the calling station.
1.6 At the “over” signal, initiated by the calling station, any available traffic in the ship’s
traffic store could be transmitted.
1.7 At the end of the communication, an “end of communication” signal should be
transmitted, whereupon the ship’s equipment should automatically revert to the “stand-by”
condition.
280 Maritime Manual
1.8 A “free channel” signal may be transmitted by a coast station where necessary to
indicate when a channel is open for traffic. The “free channel” signals should preferably be
restricted to only one channel per HF band and their duration should be kept as short as possible.
In accordance with Article 18 of the Radio Regulations and recognizing the heavy loading of the
frequencies available for narrow-band direct printing in the HF bands, “free channel” signals
should not be used in future planned systems.
1.9 The format of the “free channel” signal should be composed of signals in the 7-unit
error detecting code as listed in § 2 of Annex 1 to Recommendation ITU-R M.476 and § 2 of
Annex 1 to Recommendation ITU-R M.625. Three of these signals should be grouped into a
block, the middle signal being the “signal repetition” (RQ), the first signal of the block being
any of the signals VXKMCF TBOZA and the third signal of the block being any of the signals
VMPCYFS OIRZDA (see Recommendation ITU-R M.491). These signals should be indicated
in the ITU List of Coast Stations.
Selections of new signals should preferably be chosen to correspond to the first two digits of that
coast station’s 4-digit identification number. If this is not possible because the characters needed
are not listed above, or if this is not desired because this combination is already in use by
another coast station, it is preferred that a combination of characters be selected from those listed
above in the second part of each row, i.e. TBOZA for the first signal and OIRZDA for the third
signal of the free channel block. The signals in the block are transmitted at a modulation rate of
100 Bd and the blocks are separated by pauses of 240 ms. For manual systems this “free
channel” signal should be interrupted either by a period of no signal or by a signal or signals,
that would enable an operator to recognize the “free channel” condition by ear. An aurally
recognizable signal, e.g. a Morse signal, may be used alone as the “free channel” signal in
manual systems. At least 8 blocks of the 7-unit signal should be transmitted before interruption.
1.10 In the case of single frequency operation, as described in Recommendation
ITU-R M.692, the free channel signal should be interrupted by listening periods of at least 3 s.
1.11 General operational procedures for setting up calls between ship stations and between
ship stations and coast stations are given below and specific procedures are given in Appendix 1.
1.12 Manual procedures
1.12.1 Ship to coast station
1.12.1.1 The operator of the ship station establishes communication with the coast station by
A1A Morse telegraphy, telephony or by other means using normal calling procedures. The
operator then requests direct-printing communication, exchanges information regarding the
frequencies to be used and, when applicable, gives the ship station the direct-printing selective
call number assigned in accordance with Recommendation ITU-R M.476 or ITU-R M.625 as
appropriate, or the ship station identity assigned in accordance with the Preface to List VII A.
1.12.1.2 The operator of the coast station then establishes direct-printing communication on the
frequency agreed, using the appropriate identification of the ship.
Part B – SECTION IV – Rec. ITU-R M.492-6 281
1.12.1.3 Alternatively the operator of the ship station, using the direct-printing equipment, calls
the coast station on a predetermined coast station receive frequency using the identification of
the coast station assigned in accordance with Recommendation ITU-R M.476 or ITU-R M.625
as appropriate, or the coast station identity assigned in accordance with the Preface to
List VII A.
1.12.1.4 The operator of the coast station then establishes direct-printing communication on the
corresponding coast station transmit frequency.
1.12.2 Coast station to ship
1.12.2.1 The operator of the coast station calls the ship station by A1A Morse telegraphy,
telephony or other means, using normal calling procedures.
1.12.2.2 The operator of the ship station then applies the procedures of § 1.12.1.1 or § 1.12.1.3.
1.12.3 Intership
1.12.3.1 The operator of the calling ship station establishes communication with the called ship
station by A1A Morse telegraphy, telephony, or by other means, using normal calling
procedures. The operator then requests direct-printing communication, exchanges information
regarding the frequencies to be used and, when applicable, gives the direct-printing selective call
number of the calling ship station assigned in accordance with Recommendation ITU-R M.476
or ITU-R M.625 as appropriate, or the ship station identity assigned in accordance with the
Preface to List VII A.
1.12.3.2 The operator of the called ship station then establishes direct-printing communication
on the frequency agreed, using the appropriate identification of the calling ship.
1.13 Procedures for automatic operation
1.13.1 Ship to coast station
1.13.1.1 The ship station calls the coast station on a predetermined coast station receive
frequency, using the direct-printing equipment and the identification signal of the coast station
assigned in accordance with Recommendation ITU-R M.476 or ITU-R M.625 as appropriate, or
the coast station identity assigned in accordance with the Preface to List VII A.
1.13.1.2 The coast station’s direct-printing equipment detects the call and the coast station
responds directly on the corresponding coast station transmit frequency, either automatically or
under manual control.
1.13.2 Coast station to ship
1.13.2.1 The coast station calls the ship station on a predetermined coast station transmit
frequency, using the direct-printing equipment and the ship station direct-printing selective call
number assigned in accordance with Recommendation ITU-R M.476 or ITU-R M.625 as
appropriate, or the ship station identity assigned in accordance with the Preface to List VII A.
282 Maritime Manual
1.13.2.2 The ship station’s direct-printing equipment tuned to receive the predetermined coast
station transmit frequency detects the call, whereupon the reply is given in one of the following
ways:
a) the ship station replies either immediately on the corresponding coast station receive
frequency or at a later stage, using the procedure of § 1.12.1.3; or
b) the ship station’s transmitter is automatically started on the corresponding coast station
receive frequency and the direct-printing equipment responds by sending appropriate
signals to indicate readiness to receive traffic automatically.
1.14 Message format
1.14.1 Where the appropriate facilities are provided by the coast station, traffic may be
exchanged with the telex network:
a) in a conversational mode where the stations concerned are connected directly, either
automatically or under manual control; or
b) in a store-and-forward mode where traffic is stored at the coast station until the circuit to
the called station can be set up, either automatically or under manual control.
1.14.2 In the shore-to-ship direction, the message format should conform to normal telex
network practice (see also Appendix 1, § 2).
1.14.3 In the ship-to-shore direction, the message format should conform to the operational
procedures specified in Appendix 1, § 1.
2 Mode B (FEC)
2.1 Messages may, by prior arrangement, be sent in the B mode from a coast station or a
ship station to a number of ships or to a single ship, preceded if desired by the selective call code
of the ship(s) concerned where:
2.1.1 a receiving ship station is not permitted or not able to use its transmitter, or
2.1.2 communications are intended for more than one ship, or
2.1.3 unattended reception of the B mode is required and automatic acknowledgement is not
necessary.
In such cases, the ship station receivers should be tuned to the appropriate coast or ship station
transmitting frequency.
2.2 All B mode messages should start with “carriage return” and “line feed” signals.
2.3 When the ship station receives phasing signals in the B mode, its teleprinter should
start automatically and should stop automatically when reception of the emission ceases.
Part B – SECTION IV – Rec. ITU-R M.492-6 283
2.4 Ship stations may acknowledge the reception of B mode messages by A1A Morse
telegraphy, telephony or by other means.
3 Inter-working between equipments in accordance with Recommenda-
tions ITU-R M.476 and ITU-R M.625
3.1 Recommendation ITU-R M.625 provides for automatic inter-working with equipment
which is in accordance with Recommendation ITU-R M.476. The criteria for determining
whether one or both stations are of the Recommendation ITU-R M.476 type are the length of the
call signal and the composition of the call blocks.
3.2 If both stations have equipment in accordance with Recommendation ITU-R M.625,
automatic station identification is a part of the automatic call set-up procedures. However, if one
or both stations have equipment in accordance with Recommendation ITU-R M.476, no
automatic station identification takes place. For this reason, and because Recommendation
ITU-R M.625 accommodates the use of the 9-digit ship station identity for the direct-printing
equipment call signal, it is desirable that all new equipment be in accordance with
Recommendation ITU-R M.625 at the earliest practicable time.
3.3 In order to attain full compatibility with the large number of existing equipment, it will
be necessary to assign both a 9-digit and a 5- (or 4-) digit identity (i.e. 7- and 4-signal call
signals) to such new stations. Ship and coast station lists should contain both signals.
284 Maritime Manual
APPENDIX 1
1 Procedure for setting up a call in the ship-to-coast station direction
< ≡ ↓ GA ↑ + ?
↓1
2
3
4
< ≡ ↓ ΚΚΚΚ (7)
< ≡ ↓ GA ↑ + ?
< ≡ ↓ MSG ↑ + ?(5)
< ≡ ↓ QRC ↑ + ?
5
6
7
8
9
10
11
12
13
14
? (3)
(2)
< ≡ ↓ TLX ↑ xy +< ≡ ↓ DIRTLX ↑ xy +
< ≡ ↓ MSG ↑ +
< ≡ ↓ TGM ↑ +< ≡ ↓ URG ↑ +< ≡ ↓ RTL ↑ +< ≡ ↓ OPR ↑ +< ≡ ↓ WX ↑ +< ≡ ↓ NAV ↑ +< ≡ ↓ STA ↑ +< ≡ ↓ POS ↑ +< ≡ ↓ FREQ ↑ +< ≡ ↓ SVC ↑ +< ≡ ↓ MAN ↑ +< ≡ ↓ MED ↑ +< ≡ ↓ OBS ↑ +< ≡ ↓ HELP ↑ +
< ≡ ↓ HELP... ↑ +< ≡ ↓ AMV ↑ +< ≡ ↓ BRK ↑ +
< ≡ ↓ MULTLX ↑ xy/xy/xy +< ≡ ↓ STS ↑ x +
< ≡ ↓ VBTLX ↑ xy + < ≡ ↓ FAX ↑ xy + < ≡ ↓ TEL ↑ xy + < ≡ ↓ DATA ↑ xy + < ≡ ↓ RPT ↑ × ... + < ≡ ↓ TST ↑ + < ≡ ↓ TRF ↑ +
< ≡ ↓ INF ↑ +
< ≡ “Message reference charged
time, etc.” (8)
Coast station Ship station
Ship initiates the call
Go to step 4 or
end of communication
Note
2 a
ppli
es
Exchange answer-backs (1)
Step
Exchange answer-backs (1)
Ship transmits its
AAIC, followed by + ? (3) (4)
Message procedure (6)
(2.1) or(2.2) or(2.3) or
(2.4) or(2.5) or
(2.6) or(2.7) or(2.8) or
(2.9) or(2.10) or
(2.11) or
(2.12) or
(2.13) or(2.14) or
(2.15) or
(2.16) or(2.17) or
(2.18) or(2.19) or(2.20) or
(2.21) or(2.22) or
(2.23) or(2.24) or
(2.25) or(2.26) or
(2.27) or
(2.28) or(2.29) or(2.30)
D01
FIGURE ...[D01] = 20 CM
Part B – SECTION IV – Rec. ITU-R M.492-6 285
2 Procedure for setting up a call in the coast-to-ship station direction
Operation in the direction coast station to ship may need to be in the store-and-forward mode
owing to the fact that radio propagation conditions may not allow the setting up of a call at the
intended time.
5
6
7
↓1
2
3
4
← ≡ ↓ GA ↑ + ?
Go to step 3or
Coast station Ship stationStep
Exchange answer-backs (1)
Message procedure
If ship has traffic for coast station go to step 4 of Part 1
or
End of communication
Coast station initiates
call
Exchange answer-backs (1)
D02
FIGURE 1...[D02] = 9 CM
Notes relative to § 1 and 2:
(1) a) In automatic operation the answer-back exchange is initiated and controlled by the coast station. For calls set up by the ship station the answer-back exchange in manual operation may be initiated by the ship station.
For calls set up by the coast station the answer-back exchange in manual operation is initiated by the coast station, thereby defining the order in which the exchange takes place.
b) Answer-back code as defined in ITU-T Recommendations F.130 for ship stations and F.60 for coast stations.
(2) A coast station need not provide all of the facilities indicated. However, where specific facilities are provided, the facility codes indicated should be used. The facility “HELP” should always be available.
(2.1) MSG indicates that the ship station needs to immediately receive any messages held for it at the coast station.
286 Maritime Manual
(2.2) TLX ↑ xy indicates that the following message is for immediate connection to a store-and-forward facility located at the coast station.
y indicates the subscriber’s national telex number.
x is used where applicable to indicate the country code (ITU-T Recommendation F.69) preceded by 0 (when applicable). (Where the store-and-forward system is remote from the coast station, TLX alone may be used.)
TLXA may optionally be used instead of TLX which indicates that ship wishes to be advised (using the normal shore-to-ship procedures) when the message has been delivered to the indicated telex number.
(2.3) DIRTLX ↑ xy indicates that a direct telex connection is required.
y indicates the subscriber’s national telex number.
x is used where applicable to indicate the country code (ITU-T Recommendation F.69) preceded by 0 (when applicable).
RDL + may optionally be used to indicate that the last DIRTLX ↑ xy telex number should be redialled.
(2.4) TGM indicates that the following message is a radio telegram.
(2.5) URG indicates that the ship station needs to be connected immediately to a manual assistance operator and an audible alarm may be activated. This code should only be used in case of emergency.
(2.6) RTL indicates that the following message is a radio telex letter.
(2.7) OPR indicates that connection to a manual assistance operator is required.
(2.8) WX indicates that the ship station needs to immediately receive weather information.
(2.9) NAV indicates that the ship station needs to immediately receive navigational warnings.
(2.10) STA indicates that the ship station needs to immediately receive a status report of all store-and-forward messages which have been sent by that ship station, but which the ship station has not already received on retransmitted or non-delivered information (see also (6)). STA ↑ x may also be used where the ship station needs to immediately receive a status report of such a message where x indicates the message reference provided by the coast station.
(2.11) POS indicates that the following message contains the ship’s position. Some administrations use this information to assist in the subsequent automatic transmission or reception of messages (e.g. for calculating the optimum traffic frequency and/or the appropriate directional antennas to use).
(2.12) FREQ indicates that the following message indicates the frequency on which the ship is keeping watch.
(2.13) SVC indicates that the following message is a service message (for subsequent manual attention).
(2.14) MAN indicates that the following message is to be stored and manually forwarded to a country which cannot be accessed automatically.
(2.15) MED indicates that an urgent medical message follows.
(2.16) OBS indicates that the following message is to be sent to the meteorological organization.
(2.17) HELP indicates that the ship station needs to immediately receive a list of available facilities within the system.
Part B – SECTION IV – Rec. ITU-R M.492-6 287
(2.18) If information is needed on the application of procedures for individual facilities at a coast station, request for further details concerning the specific procedure can be obtained by the facility code HELP followed by the appropriate facility code for which the information is needed, e.g.: < ≡ ↓HELP DIRTLX ↑ + indicates that the ship station needs information on the procedures (action by ship operator) for ordering a dialogue-mode connection with a telex network subscriber via the coast station.
(2.19) AMV indicates that the following message is to be sent to the AMVER organization.
(2.20) BRK indicates that the use of the radio path is to be immediately discontinued (for use where the ship’s operator can only use a teleprinter for controlling the ARQ equipment).
(2.21) MULTLX ↑ xy/xy/xy+ indicates that the following message is a multiple address message for immediate connection to a store-and-forward facility located at the coast station.
y indicates the subscriber’s national telex number.
x is used where applicable to indicate the country code (ITU-T Recommendation F.69) preceded by 0 (when applicable).
Each separate xy indicates a different telex number to which the same message should be forwarded. At least two separate telex numbers should be included.
MULTLXA may optionally be used instead of MULTLX which indicates that the ship wishes to be advised (using the normal shore-to-ship procedures) when the messages have been delivered to the indicated telex numbers.
(2.22) STS ↑ x + indicates that the following message is for transmission to a ship using a store-and-forward facility located at the coast station. x indicates the addressed ship’s 5- or 9-digit identity number.
(2.23) INF indicates that the ship station needs to immediately receive information from the coast station’s database. Some administrations provide a variety of different database information in which case INF returns a directory listing and a subsequent facility code is used to select the desired information.
(2.24) VBTLX ↑ xy indicates that the following message should be dictated, by the coast station, to a voicebank (voice messaging) telephone number for subsequent retrieval by the addressee, and that a copy of the message should be forwarded to telex number xy. The voicebank telephone number should be included in the first line of the message text.
(2.25) FAX ↑ xy indicates that the following message should be forwarded, via the PSTN, by facsimile to the telephone number xy.
(2.26) TEL ↑ xy indicates that the following message should be telephoned, by the coast station, to the telephone number xy.
(2.27) DATA ↑ xy indicates that the following message should be forwarded by the coast station using data facilities to the subscriber number xy (via the PSTN).
(2.28) RPT ↑ xy… indicates that the ship needs to receive, using the ARQ mode, a specific identified message (e.g., earlier transmitted in the FEC mode), if still available for automatic retransmission. x… is used as the message identifier.
(2.29) TST indicates that the ship needs to receive an automatically transmitted test text (e.g. “the quick brown fox …”).
(2.30) TRF indicates that the ship needs to receive information, automatically transmitted, on tariffs currently applicable to the coast station.
(3) The symbol “?” is not necessary where the coast station is automatic. It is normally required only for manual systems.
288 Maritime Manual
(4) In cases where the coast station requires information about the relevant Accounting Authority Identification Code (AAIC), this information should be provided by the ship operator on receipt of the combination < ≡ ↓ QRC ↑ + from the coast station.
Some coast stations may request additional information, e.g. ship’s name, call sign, etc.
(5) This sequence may be preceded where necessary by suitable prompts or facility selection information and, if appropriate, any consequent ship station reply, or may be deleted where not applicable (e.g. where facility codes WX, NAV, STA, MSG or HELP are input at step 4). Where facility code DIRTLX ↑ xy was input at step 4, this sequence may be replaced by the distant end answer-back or by any service signal (e.g. NC, OCC, etc.) received from the telex network.
(6) Message procedures depend on which facility is used:
For TLX where the store-and-forward system is remote from the coast station, ITU-T Recommendation F.72 may apply. Where the store-and-forward system is located at the coast station, the complete information content of the message sent at this step will be forwarded to the subscriber whose telex number is given by xy.
For DIRTLX, see ITU-T Recommendation F.60.
For TGM, see ITU-T Recommendations F.1 and F.31.
For SVC and MED, the message will normally be plain text and no specific message procedure is required.
For RTL, the message will be plain text but should include the postal address of the addressee.
For STA, the appropriate status information is returned to the ship in accordance with ITU-T Recommendation F.72, § 11.3 and 11.4.
For POS and FREQ, specific national procedures may apply.
(7) This sequence of 4 K’s “KKKK” (4 combination No. 11 signals in the letter case) indicates that any network connection should be cleared but that the radio path should be maintained and that the procedure should immediately proceed to step 11. This sequence may be used elsewhere in the procedure in which case the procedure reverts to step 3.
(8) This step is optional and may not apply to all facilities.
Part B – SECTION IV – Rec. ITU-R M.541-9 289
RECOMMENDATION ITU-R M.541-9
Operational procedures for the use of digital selective-calling
equipment in the maritime mobile service
(1978-1982-1986-1990-1992-1994-1995-1996-1997-2004)
Summary
The Recommendation contains the operational procedures for digital selective-calling
(DSC) equipment whose technical characteristics are given in Recommendation
ITU-R M.493. The Recommendation contains five annexes. In Annexes 1 and 2 the
provisions and procedures are described for distress, urgency and safety calls and for
routine calls, respectively. In Annexes 3 and 4 the operational procedures for ships and
for coast stations are described and Annex 5 lists the frequencies to be used for DSC.
The ITU Radiocommunication Assembly,
considering
a) that digital selective-calling (DSC) will be used as described in
Recommendation ITU-R M.493;
b) that the requirements of Chapter IV of the International Convention for the
Safety of Life at Sea (SOLAS), 1974, as amended, for the Global Maritime Distress and
Safety System (GMDSS) are based on the use of DSC for distress alerting and calling
and that operational procedures are necessary for the use of that system;
c) that, as far as is practicable, operational procedures in all frequency bands and
for all types of communications should be similar;
d) that DSC may provide a useful supplementary means of transmitting a distress
alert in addition to the provisions of transmitting the distress alert by existing methods
and procedures in the Radio Regulations (RR);
e) that conditions when alarms have to be actuated should be specified,
recommends
1 that the technical characteristics of equipment used for DSC in the maritime
mobile service should be in conformity with the relevant ITU-R Recommendations;
290 Maritime Manual
2 that the operational procedures to be observed in the MF, HF and VHF bands
for DSC should be in accordance with Annex 1 for distress and safety calls and
Annex 2 for other calls;
3 that provisions should be made at stations equipped for DSC for:
3.1 the manual entry of address, type of call, category and various messages into
a DSC sequence;
3.2 the verification and if necessary the correction of such manually formed
sequences;
3.3 a specific aural alarm and visual indication to indicate receipt of a distress or
urgency call or a call having distress category. It should not be possible to disable this
alarm and indication. Provisions should be made to ensure that they can be reset only
manually;
3.4 aural alarm(s) and visual indication for calls other than distress and urgency.
The aural alarm(s) may be capable of being disabled;
3.5 such visual indicators to indicate:
3.5.1 type of received call address (to all stations, to a group of stations,
geographical, individual);
3.5.2 category;
3.5.3 identity of calling station;
3.5.4 numerical or alpha-numerical type of information, e.g. frequency information
and telecommand;
3.5.5 type of “end of sequence” character;
3.5.6 detection of errors, if any;
3.6 monitoring the DSC channel to determine the presence of a signal and, except
for distress, urgency, and non-test safety calls, provide facilities for automatically
preventing the transmission of a DSC call until the channel is free;
4 that the equipment should be simple to operate;
5 that the operational procedures given in Annexes 3 and 4, which are based on
the relevant procedures from Annexes 1 and 2 and from the RR, be used as guidance for
ships and coast stations;
6 that the frequencies used for distress and safety purposes using DSC are those
contained in Annex 5 to this Recommendation (see RR Appendix 15).
Part B – SECTION IV – Rec. ITU-R M.541-9 291
NOTE 1 – The following definitions are used throughout this Recommendation:
Single frequency: the same frequency is used for transmission and reception.
Paired frequencies: frequencies which are associated in pairs; each pair consisting of
one transmitting and one receiving frequency.
International DSC frequencies: those frequencies designated in the RR for exclusive
use for DSC on an international basis.
National DSC frequencies: those frequencies assigned to individual coast stations or a
group of stations on which DSC is permitted (this may include working frequencies as
well as calling frequencies). The use of these frequencies must be in accordance with
the RR.
Automatic DSC operation at a ship station: a mode of operation employing automatic
tunable transmitters and receivers, suitable for unattended operation, which provide for
automatic call acknowledgements upon reception of a DSC and automatic transfer to
the appropriate working frequencies.
Call attempt: one or a limited number of call sequences directed to the same stations on
one or more frequencies and within a relatively short time period (e.g. a few minutes).
A call attempt is considered unsuccessful if a calling sequence contains the symbol RQ
at the end of the sequence and no acknowledgement is received in this time interval.
Annex 1
Provisions and procedures for distress, urgency and safety calls
1 Introduction
The terrestrial elements of the GMDSS adopted by the 1988 Amendments to the
International Convention for SOLAS, 1974, are based on the use of DSC for distress
and safety communications.
1.1 Method of calling
The provisions of RR Chapter VII are applicable to the use of DSC in cases of distress,
urgency or safety.
292 Maritime Manual
2 DSC distress alert
The DSC distress alert provides for alerting, self-identification, ship’s position
including time, and nature of distress as defined in the RR (See RR Chapter VII).
3 Procedures for DSC distress alerts
3.1 Transmission by a mobile unit in distress
3.1.1 The DSC equipment should be capable of being preset to transmit the distress
alert on at least one distress alerting frequency.
3.1.2 The distress alert shall be composed in accordance with Recommendation
ITU-R M.493; the ship’s position information, the time at which it was taken and the
nature of distress should be entered as appropriate. If the position of the ship cannot be
entered, then the position information signals shall be transmitted automatically as the
digit 9 repeated ten times. If the time cannot be included, then the time information
signals shall be transmitted automatically as the digit 8 repeated four times.
3.1.3 Distress alert attempt
At MF and HF a distress alert attempt may be transmitted as a single frequency or a
multi-frequency call attempt. At VHF only single frequency call attempts are used.
3.1.3.1 Single frequency call attempt
A distress alert attempt should be transmitted as 5 consecutive calls on one frequency.
To avoid call collision and the loss of acknowledgements, this call attempt may be
transmitted on the same frequency again after a random delay of between 3 ½ and
4 ½ min from the beginning of the initial call. This allows acknowledgements arriving
randomly to be received without being blocked by retransmission. The random delay
should be generated automatically for each repeated transmission, however it should be
possible to override the automatic repeat manually.
At MF and HF, single frequency call attempts may be repeated on different frequencies
after a random delay of between 3 ½ and 4 ½ min from the beginning of the initial call.
However, if a station is capable of receiving acknowledgements continuously on all
distress frequencies except for the transmit frequency in use, then single frequency call
attempts may be repeated on different frequencies without this delay.
3.1.3.2 Multi-frequency call attempt
A distress alert attempt may be transmitted as up to 6 consecutive (see Note 1) calls
dispersed over a maximum of 6 distress frequencies (1 at MF and 5 at HF). Stations
transmitting multi-frequency distress alert attempts should be able to receive
acknowledgements continuously on all frequencies except for the transmit frequency in
use, or be able to complete the call attempt within 1 min.
Part B – SECTION IV – Rec. ITU-R M.541-9 293
Multi-frequency call attempts may be repeated after a random delay of between 3 ½ and
4 ½ min from the beginning of the previous call attempt.
NOTE 1 – A VHF call may be transmitted simultaneously with an MF/HF call.
3.1.4 Distress
In the case of distress the operator should:
3.1.4.1 enter the desired mode of the subsequent communication and if time
permits, enter the ship’s position and time (see Note 1) it was taken and the nature of
distress (see Note 1);
NOTE 1 – If these are not provided automatically.
3.1.4.2 select the distress frequency(ies) to be used (see Note 1 of § 3.1.4.1);
3.1.4.3 activate the distress alert attempt by a dedicated distress button.
3.2 Reception
The DSC equipment should be capable of maintaining a reliable watch on a 24-hour
basis on appropriate DSC distress alerting frequencies.
3.3 Acknowledgement of distress alerts
Acknowledgements of distress alerts should be initiated manually.
Acknowledgements should be transmitted on the same frequency as the distress alert
was received.
3.3.1 Distress alerts should normally be acknowledged by DSC only by appropriate
coast stations. Coast stations should, in addition, set watch on radiotelephony and, if the
“mode of subsequent communication” signal in the received distress alert indicates
teleprinter, also on narrow-band direct-printing (NBDP) (see Recommendation ITU-R
M.493). In both cases, the radiotelephone and NBDP frequencies should be those
associated with the frequency on which the distress alert was received.
3.3.2 Acknowledgements by coast stations of DSC distress alerts transmitted on MF
or HF should be initiated with a minimum delay of 1 min after receipt of a distress alert,
and normally within a maximum delay of 2 ¾ min. This allows all calls within a single
frequency or multi-frequency call attempt to be completed and should allow sufficient
time for coast stations to respond to the distress alert. Acknowledgements by coast
stations on VHF should be transmitted as soon as practicable.
294 Maritime Manual
3.3.3 The acknowledgement of a distress alert consists of a single DSC
acknowledgement call which should be addressed to “all ships” and include the
identification (see Recommendation ITU-R M.493) of the ship whose distress alert is
being acknowledged.
3.3.4 Ships receiving a DSC distress alert from another ship should set watch on an
associated radiotelephone distress and safety traffic frequency and acknowledge the call
by radiotelephony.
If a ship station continues to receive a DSC distress alert on an MF or VHF channel, a
DSC acknowledgement should be transmitted to terminate the call only after consulting
with a Rescue Coordination Centre or a Coast Station and being directed to do so.
3.3.5 The automatic repetition of a distress alert attempt should be terminated
automatically on receipt of a DSC distress acknowledgement.
3.3.6 When distress, urgency, and safety traffic cannot be successfully conducted
using radiotelephony, an affected station may indicate its intention to conduct
subsequent communications on the associated frequency for NBDP telegraphy.
3.4 Distress relays
Distress relay calls should be initiated manually.
3.4.1 A distress relay call should use the telecommand signal “distress relay” in
accordance with Recommendation ITU-R M.493 and the calling attempt should follow
the procedures described in § 3.1.3 to 3.1.3.2 for distress alerts, except that the alert is
sent manually as a single call on a single frequency.
3.4.2 Any ship, receiving a distress alert on an HF channel which is not
acknowledged by a coast station within 5 min, should transmit a distress relay call to
the appropriate coast station.
3.4.3 Distress relay calls transmitted by coast stations, or by ship stations addressed
to more than one vessel, should be acknowledged by ship stations using radiotelephony.
Distress relay calls transmitted by ship stations should be acknowledged by a coast
station transmitting a “distress relay acknowledgement” call in accordance with the
procedures for distress acknowledgements given in § 3.3 to 3.3.3.
4 Procedures for DSC urgency and safety calls
4.1 DSC, on the distress and safety calling frequencies, should be used by coast
stations to advise shipping, and by ships to advise coast stations and/or ship stations, of
the impending transmission of urgency, vital navigational and safety messages, except
where the transmissions take place at routine times. The call should indicate the
working frequency which will be used for the subsequent transmission of an urgent,
vital navigational or safety message.
Part B – SECTION IV – Rec. ITU-R M.541-9 295
4.2 The announcement and identification of medical transports should be carried
out by DSC techniques, using appropriate distress and safety calling frequencies. Such
calls should use the category “urgency”, and telecommand “medical transport” and be
addressed to all ships at VHF and Geographic Area at MF/HF.
4.3 The operational procedures for urgency and safety calls should be in
accordance with the relevant parts of Annex 3, § 2.1 or 2.2 and 3.1. or 3.2.
5 Testing the equipment used for distress and safety calls
Testing on the exclusive DSC distress and safety calling frequencies should be avoided
as far as possible by using other methods. VHF, MF and HF test calls should be in
accordance with Recommendation ITU-R M.493 (see Table 4.7) and the call may be
acknowledged by the called station. Normally there would be no further communication
between the two stations involved.
Annex 2
Provisions and procedures for routine calls
1 Frequency/channels
1.1 As a rule, paired frequencies should be used at HF and MF, in which case an
acknowledgement is transmitted on the frequency paired with the frequency of the
received call. In exceptional cases for national purposes a single frequency may be
used. If the same call is received on several calling channels, the most appropriate shall
be chosen to transmit the acknowledgement. A single frequency channel should be used
at VHF.
1.2 International calling
The paired frequencies listed in RR Appendix 17, Part A and in Annex 5 of this
Recommendation should be used for international DSC calling.
1.2.1 At HF and MF international DSC frequencies should only be used for shore-
to-ship calls and for the associated call acknowledgements from ships fitted for
automatic DSC operation where it is known that the ships concerned are not listening to
the coast station’s national frequencies.
296 Maritime Manual
1.2.2 All ship-to-shore DSC calling at HF and MF should preferably be done on the
coast station’s national frequencies.
1.3 National calling
Coast stations should avoid using the international DSC frequencies for calls that may
be placed using national frequencies.
1.3.1 Ship stations should keep watch on appropriate national and international
channels. (Appropriate measures should be taken for an even loading of national and
international channels.)
1.3.2 Administrations are urged to find methods and negotiate terms to improve the
utilization of the DSC channels available, e.g.:
– coordinated and/or joint use of coast station transmitters;
– optimizing the probability of successful calls by providing information to ships
on suitable frequencies (channels) to be watched and by information from
ships to a selected number of coast stations on the channels watched on-board.
1.4 Method of calling
1.4.1 The procedures set out in this section are applicable to the use of DSC
techniques, except in cases of distress, urgency or safety, to which the provisions of RR
Chapter VII are applicable.
1.4.2 The call shall contain information indicating the station or stations to which
the call is directed, and the identification of the calling station.
1.4.3 The call should also contain information indicating the type of communication
to be set up and may include supplementary information such as a proposed working
frequency or channel; this information shall always be included in calls from coast
stations, which shall have priority for that purpose.
1.4.4 An appropriate digital selective calling channel chosen in accordance with the
provisions of RR Nos. 52.128 to 52.137 or Nos. 52.145 to 52.153, as appropriate, shall
be used for the call.
2 Operating procedures
The technical format of the call sequence shall be in conformity with the relevant
ITU-R Recommendations.
The reply to a DSC requesting an acknowledgement shall be made by transmitting an
appropriate acknowledgement using DSC techniques.
Part B – SECTION IV – Rec. ITU-R M.541-9 297
Acknowledgements may be initiated either manually or automatically. When an
acknowledgement can be transmitted automatically, it shall be in conformity with the
relevant ITU-R Recommendations.
The technical format of the acknowledgement sequence shall be in conformity with the
relevant ITU-R Recommendations.
For communication between a coast station and a ship station, the coast station shall
finally decide the working frequency or channel to be used.
The forwarding traffic and the control for working for radiotelephony shall be carried
out in accordance with Recommendation ITU-R M.1171.
A typical DSC calling and acknowledgement sequence contains the following signals
(see Recommendation ITU-R M.493).
Composition of a typical routine DSC calling and acknowledgement sequence
2.1 Coast station initiates call to ship station (see Note 1)
Figures 1 and 2 illustrate the procedures below in flow chart and by time sequence
diagram respectively.
NOTE 1 – See Recommendations ITU-R M.689 and ITU-R M.1082 for further details of
procedures applicable only to the semi-automatic/automatic services.
2.1.2 If a direct connection exists between the calling subscriber and the coast
station, the coast station asks the calling subscriber for the approximate position of the
ship.
Signal Method of composition
– format specifier operator selected
– address operator entered
– category (routine) automatically selected
– self-identification pre-programmed
– telecommand information seleccionada por el operador
– frequency information (if appropriate) operator selected or entered
– telephone number (semi-
automatic/automatic
ship-to-shore connections only) operator entered
– end of sequence signal automatically selected.
298 Maritime Manual
2.1.3 If the ship’s position cannot be indicated by the caller, the coast station
operator tries to find the location in the information available at the coast station.
2.1.4 The coast station checks to see whether the call would be more appropriate
through another coast station (see § 1.3.2).
2.1.5 The coast station checks to see whether the transmission of a DSC is
inappropriate or restricted (e.g. ship not fitted with DSC or barred).
2.1.6 Assuming a DSC is appropriate the coast station composes the calling
sequence as follows:
– selects format specifier,
– enters address of the ship,
– selects category,
– selects telecommand information,
– inserts working frequency information in the message part of the sequence, if
appropriate,
– usually selects “end of sequence” signal “RQ”. However, if the coast station
knows that the ship station cannot respond or the call is to a group of ships the
frequency is omitted and the end of sequence signal should be 127, in which
case the following procedures (§ 2.1.13 to 2.1.15) relating to an
acknowledgement are not applicable.
Part B – SECTION IV – Rec. ITU-R M.541-9 299
0541-01
2.1.2
2.1.3
2.1.42.1.5
2.1.62.1.7
2.1.8
2.1.8.1
2.1.12
2.1.9
2.1.8.1
2.1.14
2
2.1.13.2
2.1.13.2
2.1.14.2
2.1.13.4
2.1.13.3
2.1.14
1
2.1.13
2.1.13.32.1.13.4 2.1.13.1
2.1.13.12.1.13.3/4
2.1.13.12.1.13.3/4
2.1.13.1
2.1.14
2.1.8.2
2.1.11
1/10 min6/24 h 2.1.13.4
2.1.14
Autom.
2.1.15
2.1.8.1
SHORE(coast station)
Ask caller forposition of ship
if a directconnection exists
NoPosition?
Yes
Try to findthe position
of ship
Is callappropriate?
No
Compose andverify a calling
sequence
Select callingfrequency
Monitor theselected calling
frequency
YesBusy?
Transmitthe callingsequence
Doestransmitted
sequence containRQ?
No
Yes
Monitorreceivingchannel
YesIs ack.received?
No
Checktransmission
interval
No Is interval long
enough?
Yes
YesIs ship
on workingchannel?
No
No Has callattempt beencompleted?
Check thenumber of
call attempts
Can callattempt berepeated?
Yes
No
Contact withcaller if
necessary
END
Wait for acall from ship
station
END
Contact shipstation on working
channel agreed
Yes
No Is theship able to comply
immediately?
See Fig. 3
SHIP
Record andindicatemessagereceived
Withacknowledgement
RQ?
No
Yes
TXautom. ormanu.?
Automaticcomposition of
acknowledgementsequence
Checktransmission
interval
Isinterval long
enough?
Transmitautomatically the acknowledgement
YesWith“unable tocomply”
No
Contact coaststation on
working channelagreed
Iscontact success-
ful?
Yes
END
Monitor workingchannel proposed
if appropriate
Manual
Canacknowledgement
be transmittedwithin 5 min of
receipt?
Yes
Compose andverify an
acknowledgement sequence
No
Compose andverify a calling
sequence
SeeFig. 3
FIGURE 1
Flow chart of operational procedures for calling in the shore-to-ship direction
Yes
Yes
No
Yes
No
No
300 Maritime Manual
0541-02
t1
t4
t1
t3
t1
t2
t1
t5
t1
t3
t1
t4t1
t2
t1
t5
t1
t3
TX RX RX TX f1 fl′F, A(s), C, I(c), T1, T2, f1, RQ
F, A(c), C, I(s), T1, T2, f1, BQ
F, A(s), C, I(c), T1, T2, f1, RQ
F, A(c), C, I(s), T1 (104)
T2, f1, BQ
F, A(c), C, I(s), T1, T2, f1, RQ
F, A(s), C, I(c), T1, T2, f1, RQ
F, A(c), C, I(s), T1, T2, f1, RQ
F, A(s), C, I(c), T1 (104),T2 (103), f1, BQ
F, A(s), C, I(c), T1, T2, f1, BQ
Coaststation
Shipstation
Workingfrequencies
Contact on
working
frequencies
a) Automated transmitter (able to comply)
b) Automated transmitter (unable to comply)
Contact on
working
frequencies
Contact on
working
frequencies
c) Ship transmitter not automated. Ship makes a delayed (>5 min) response to coast station and encounters queue on working frequency
: transmission time of a DSC sequence: interval between the DSC reception at the ship and transmission from the ship after the operator’s appearance in the radio room (from several minutes up to several hours): transition time from calling to working frequency including, if necessary, the time for working channel clearing (queue waiting time): as defined in § 2.1.13.2: time for coast station to prepare acknowledge- ment (see § 2.2.6)
1
2
3
4
5
FIGURE 2
Examples of timing diagrams for calling in shore-to-ship direction
tt
t
t
t
F
I
CT1
T2
f1, f1′RQ, BQ
A
: format specifier: called station address
: calling station self-identification
: category: first telecommand signal, (104) indicates unable to comply: second telecommand signal, (103) indicates queue: working frequencies: end of sequence signals
suffix (c) or (s) indicates coaststation or ship station respectively
Part B – SECTION IV – Rec. ITU-R M.541-9 301
2.1.7 The coast station verifies the calling sequence.
The call shall be transmitted once on a single appropriate calling channel or frequency
only. Only in exceptional circumstances may a call be transmitted simultaneously on
more than one frequency.
2.1.8 The coast station operator chooses the calling frequencies which are most
suitable for the ship’s location.
2.1.8.1 After checking as far as possible that there are no calls in progress, the coast
station operator initiates the transmission of the sequence on one of the frequencies
chosen. Transmission on any one frequency should be limited to no more than 2 call
sequences separated by intervals of at least 45 s to allow for reception of an
acknowledgement from the ship.
2.1.8.2 If appropriate, a “call attempt” may be transmitted, which may include the
transmission of the same call sequence on other frequencies (if necessary with a change
of working frequency information to correspond to the same band as the calling
frequency) made in turn at intervals of not less than 5 min, following the same pattern
as in § 2.1.8.1.
2.1.9 If an acknowledgement is received further transmission of the call sequence
should not take place.
The coast station shall then prepare to transmit traffic on the working channel or
frequency it has proposed.
2.1.10 The acknowledgement of the received call should only be transmitted upon
receipt of a calling sequence which terminates with an acknowledgement request.
2.1.11 When a station called does not reply, the call attempt should not normally be
repeated until after an interval of at least 15 min. The same call attempt should not be
repeated more than five times every 24 h. The aggregate of the times for which
frequencies are occupied in one call attempt, should normally not exceed 1 min.
The following procedures apply at the ship:
2.1.12 Upon receipt of a calling sequence at the ship station, the received message
should be displayed.
2.1.13 When a received call sequence contains an end of sequence signal “RQ”, an
acknowledgement sequence should be composed and transmitted.
The format specifier and category information should be identical to that in the received
calling sequence.
302 Maritime Manual
2.1.13.1 If the ship station is not equipped for automatic DSC operation, the ship’s
operator initiates an acknowledgement to the coast station after a delay of at least 5 s
but no later than 4 ½ min of receiving the calling sequence, using the ship-to-shore
calling procedures detailed in § 2.2. However the transmitted sequence should contain
a “BQ” end of sequence signal in place of the “RQ” signal.
If such an acknowledgement cannot be transmitted within 5 min of receiving the calling
sequence then the ship station should instead transmit a calling sequence to the coast
station using the ship-to-shore calling procedure detailed in § 2.2.
2.1.13.2 If the ship is equipped for automatic DSC operation, the ship station
automatically transmits an acknowledgement with an end of sequence signal “BQ”. The
start of the transmission of this acknowledgement sequence should be within 30 s for
HF and MF or within 3 s for VHF after the reception of the complete call sequence.
2.1.13.3 If the ship is able to comply immediately the acknowledgement sequence
should include a telecommand signal which is identical to that received in the calling
sequence indicating that it is able to comply.
If no working frequency was proposed in the call, the ship station should include a
proposal for a working frequency in its acknowledgement.
2.1.13.4 If the ship is not able to comply immediately the acknowledgement
sequence should include the telecommand signal 104 (unable to comply), with a second
telecommand signal giving additional information (see Recommendation
ITU-R M.493).
At some later time when the ship is able to accept the traffic being offered, the ship’s
operator initiates a call to the coast station using the ship-to-shore calling procedures
detailed in § 2.2.
2.1.14 If a call is acknowledged indicating ability to comply immediately and
communication between coast station and ship station on the working channel agreed is
established, the DSC call procedure is considered to be completed.
2.1.15 If the ship station transmits an acknowledgement which is not received by the
coast station then this will result in the coast station repeating the call (in accordance
with § 2.1.11). In this event the ship station should transmit a new acknowledgement. If
no repeated call is received the ship station should transmit an acknowledgement or
calling sequence in accordance with § 2.1.13.1.
Part B – SECTION IV – Rec. ITU-R M.541-9 303
2.2 Ship station initiates call to coast station (see Note 1)
Figures 3 and 4 illustrate the procedures below in flow chart and by time sequence
diagram respectively.
This procedure should also be followed both as a delayed response to a call received
earlier from the coast station (see § 2.1.13.1) and to initiate traffic from the ship station.
NOTE 1 – See Recommendations ITU-R M.689 and ITU-R M.1082 for further details of
procedures applicable only to the semi-automatic/automatic services.
2.2.1 The ship composes the calling sequence as follows:
– operator selects the format specifier,
– operator enters address,
– automatically selected category,
– pre-programmed self-identification,
– operator selects the telecommand information,
– operator inserts (selects or enters) working frequency, or enters position (for
MF/HF only) information in the message part of the sequence if appropriate,
– operator enters telephone number required (semi-automatic/automatic
connections only),
– automatically selected “end of sequence” signal RQ.
304 Maritime Manual
0541-03
2.2.1/2.2.2
1
2.1.13.1
2.2.3
2.2.4
2.1.13.1
2
2.2.4
2.2.5/2.2.9
2.1.13.4
2.2.6
2.2.6
2.2.8 2.2.8
2.2.7
2.2.5
SHIP
Compose andverify a calling
sequence
SeeFig. 1
Selectcalling
frequency
Monitorthe callingfrequency
Busy?Yes
Yes
No
Is this a calling
sequence?
See Fig. 1
Transmit theacknowledgement
sequence
Transmitthe callingsequence
Checkreceivingchannel
Is acknowledgement
received?
Yes
Checktransmission
interval
Isinterval long
enough?
No
Yes
Isanother attempt
required?
Yes
No
No YesWith
“unable tocomply”?
SHORE(coast station)
Record andindicatemessagereceived
Compose andverify an
acknowledgement sequence
Select acknowledgement
frequency
Delay ifnecessary(manual
connections)
Transmit the acknowledgement
sequence
Contact shipstation on
working channelagreed
END END
Contact coaststation on
working channelagreed
Yes
Yes
No
No
Is alternativefrequencyproposed?
Is alternativefrequency
acceptable?
Ship transmit callindicating “unable
to comply”
FIGURE 3
Flow chart of operational procedures for calling in the ship-to-shore direction
No
No
Part B – SECTION IV – Rec. ITU-R M.541-9 305
0541-04
t1
t5
t3
t1
t1
t5
t3
t1
F, A(c), C, I(s), T1, T2, f1, RQ
F, A(s), C, I(c), T1 (104),T2 (103), f1, BQ
F, A(c), C, I(s), T1, T2, f1, RQ
F, A(s), C, I(c), T1, T2, f1, BQ
TX RX RX TX f1 f1′
Contact onworking
frequencies
Contact on
working
frequencies
a) Able to comply immediately
b) Queue exists on working frequency
FIGURE 4
Examples of timing diagrams for calling in ship-to-shore direction
Coast station
Shipstation
Workingfrequencies
: transmission time of a DSC sequence: transition time from calling to working frequency including, if necessary, the time for
working channel clearing (queue waiting time)
: time for coast station to prepare acknowledgement (see § 2.2.6)
: format specifier: called station address
t1
t3
t5
F
A
: calling station
self-identification
: category
: first telecommand signal, (104) indicates unable to comply: second telecommand signal, (103) indicates queue
: working frequencies
: end of sequence signals
suffix (c) or (s) indicates coast station
or ship station respectively
I
CT1
T2
f1, f1'
RQ, BQ
2.2.2 The ship verifies the calling sequence.
2.2.3 The ship selects the single most appropriate calling frequency preferably using
the coast station’s nationally assigned calling channels, for which purpose it shall send
a single calling sequence on the selected frequency.
2.2.4 The ship initiates the transmission of the sequence on the frequency selected
after checking as far as possible that there are no calls in progress on that frequency.
306 Maritime Manual
0541-05
(1)
(2)
(3)
(4)
(5)
(3)
(3)
(4)
(2)
(5)
SHORE(coast station)
or SHIP
Calling Calling/acknowledgement
Select acknowledgementBQ as EOS signal
Unableto comply?
Yes
No
NoAlternativefrequency proposal?
Yes
Enter frequencyproposal
Select 1st telecommand“unable to comply” (104)
and 2nd telecommand as appropriate
Selecttelecommandinformation
Selectcategory
Enteraddress
Select formatspecifier
2.1.6 (Coast)2.2.1 (Ship)
Withfrequency?
No
Yes
Select frequencyof working
channel
No Semi-automatic/automatic
ship-to-shore connection
Yes
Enter telephonenumber
END
Queue?No
Yes
Entertelecommands104 and 103
Selecttelecommandinformation
FIGURE 5
Composition procedures for calling and acknowledgement sequences(for calls other than distress and safety)
Normally acknowledgement RQ may automatically be selected as an EOS signal of a callingsequence to an individual station.
The format specifier and the category are automatically transferred from the receivedcall.The self-ID in the received sequence is automatically transferred into theaddress part of acknowledgement sequence by selecting acknowledgement BQ.
The frequency information is automatically transferred from the received call.This procedure is only for coast stations.
When able to comply, and no queue exists, then the telecommand information isautomatically transferred from the received call.
“Routine” or“ship business
priority”
Select EOSsignal(1)
Acknowledgement 2.1.13 (Ship)2.2.6 (Coast)
Part B – SECTION IV – Rec. ITU-R M.541-9 307
2.2.5 If a called station does not reply, the call sequence from the ship station should
not normally be repeated until after an interval of at least 5 min for manual connections,
or 5 s or 25 s in the case of semi-automatic/automatic VHF or MF/HF connections
respectively. These repetitions may be made on alternative frequencies if appropriate.
Any subsequent repetitions to the same coast station should not be made until at least
15 min have elapsed.
2.2.6 The coast station should transmit an acknowledgement sequence (after
checking as far as possible that there are no calls in progress on the frequency selected),
after a delay of at least 5 s but not later than 4 ½ min for manual connections, or, within
3 s for semi-automatic/automatic connections, containing the format specifier, the
address of the ship, the category, the coast station self-identification and:
– if able to comply immediately on the working frequency suggested, the same
telecommand and frequency information as in the call request;
– if no working frequency was suggested by the ship station then the
acknowledgement sequence should include a channel/frequency proposal;
– if not able to comply on the working frequency suggested but able to comply
immediately on an alternative frequency, the same telecommand information
as in the call request but an alternative working frequency;
– if unable to comply immediately the telecommand signal 104 with a second
telecommand signal giving additional information. For manual connections
only, this second telecommand signal may include a queue indication.
The end of sequence signal BQ should also be included.
2.2.7 For manual connections, if a working frequency is proposed in accordance
with § 2.2.6 but this is not acceptable to the ship station, then the ship station should
immediately transmit a new call requesting an alternative frequency.
2.2.8 If an acknowledgement is received further transmission of the call sequence
should not take place. On receipt of an acknowledgement which indicates ability to
comply, the DSC procedures are complete and both coast station and ship station
should communicate on the working frequencies agreed with no further exchange of
DSC calls.
2.2.9 If the coast station transmits an acknowledgement which is not received at the
ship station then the ship station should repeat the call in accordance with § 2.2.5.
2.3 Ship station initiates call to ship station
The ship-to-ship procedures should be similar to those given in § 2.2, where the
receiving ship station complies with the procedures given for coast stations, as
appropriate, except that, with respect to § 2.2.1, the calling ship should always insert
working frequency information in the message part of the calling sequence.
308 Maritime Manual
Annex 3
Operational procedures for ships for DSC communications
on MF, HF and VHF
Introduction
Procedures for DSC communications on MF and VHF are described in § 1 to 5 below.
The procedures for DSC communications on HF are in general the same as for MF and
VHF. Special conditions to be taken into account when making DSC communications
on HF are described in § 6 below.
1 Distress
1.1 Transmission of DSC distress alert
A distress alert should be transmitted if, in the opinion of the Master, the ship or a
person is in distress and requires immediate assistance.
A DSC distress alert should as far as possible include the ship’s last known position and
the time (in UTC) when it was valid. The position and the time may be included
automatically by the ship’s navigational equipment or may be inserted manually.
The DSC distress alert is transmitted as follows:
– tune the transmitter to the DSC distress channel (2 187.5 kHz on MF,
channel 70 on VHF (see Note 1)).
NOTE 1 – Some maritime MF radiotelephony transmitters shall be tuned to a
frequency 1 700 Hz lower than 2 187.5 kHz, i.e. 2 185.8 kHz, in order to transmit the
DSC distress alert on 2 187.5 kHz;
– if time permits, key in or select on the DSC equipment keyboard
– the nature of distress,
– the ship’s last known position (latitude and longitude),
– the time (in UTC) the position was valid,
– type of subsequent distress communication (telephony),
in accordance with the DSC equipment manufacturer’s instructions;
– transmit the DSC distress alert;
– prepare for the subsequent distress traffic by tuning the transmitter and the
radiotelephony receiver to the distress traffic channel in the same band, i.e.
2 182 kHz on MF, channel 16 on VHF, while waiting for the DSC distress
acknowledgement.
Part B – SECTION IV – Rec. ITU-R M.541-9 309
1.2 Actions on receipt of a distress alert
Ships receiving a DSC distress alert from another ship should normally not
acknowledge the distress alert by DSC since acknowledgement of a DSC distress alert
by use of DSC is normally made by coast stations only (see Annex 1 § 3.3.4 and
Annex 3 § 6.1.4).
If a ship station continues to receive a DSC distress alert on an MF or VHF channel, a
DSC acknowledgement should be transmitted to terminate the call only after consulting
with a Rescue Coordination Centre or a Coast Station and being directed to do so.
Ships receiving a DSC distress alert from another ship should also defer the
acknowledgement of the distress alert by radiotelephony for a short interval, if the ship
is within an area covered by one or more coast stations, in order to give the coast station
time to acknowledge the DSC distress alert first.
Ships receiving a DSC distress alert from another ship shall:
– watch for the reception of a distress acknowledgement on the distress channel
(2 187.5 kHz on MF and channel 70 on VHF);
– prepare for receiving the subsequent distress communication by tuning the
radiotelephony receiver to the distress traffic frequency in the same band in
which the DSC distress alert was received, i.e. 2 182 kHz on MF, channel 16
on VHF;
– acknowledge the receipt of the distress alert by transmitting the following by
radiotelephony on the distress traffic frequency in the same band in which the
DSC distress alert was received, i.e. 2 182 kHz on MF, channel 16 on VHF:
– “MAYDAY”,
– the 9-digit identity of the ship in distress, repeated 3 times,
– “this is”,
– the 9-digit identity or the call sign or other identification of own ship,
repeated 3 times,
– “RECEIVED MAYDAY”.
1.3 Distress traffic
On receipt of a DSC distress acknowledgement the ship in distress should commence
the distress traffic by radiotelephony on the distress traffic frequency (2 182 kHz on
MF, channel 16 on VHF) as follows:
– “MAYDAY”,
– “this is”,
– the 9-digit identity and the call sign or other identification of the ship,
310 Maritime Manual
– the ship’s position in latitude and longitude or other reference to a known
geographical location,
– the nature of distress and assistance wanted,
– any other information which might facilitate the rescue.
1.4 Transmission of a DSC distress relay call
In no case is a ship permitted to transmit an all ships DSC distress relay call on receipt
of a DSC distress alert on either VHF or MF channels. If no aural watch is present on
the relative channel (2 182 kHz on MF, channel 16 on VHF), the coast station should be
contacted by sending an individual DSC distress relay call.
1.4.1 Transmission of a DSC distress relay call on behalf of someone else
A ship knowing that another ship is in distress shall transmit a DSC distress relay call
if:
– the ship in distress is not itself able to transmit the distress alert,
– the Master of the ship considers that further help is necessary.
The DSC distress relay call is transmitted as follows:
– tune the transmitter to the DSC distress channel (2 187.5 kHz on MF,
channel 70 on VHF),
– select the distress relay call format on the DSC equipment,
– key in or select on the DSC equipment keyboard:
– All Ships Call (VHF). Geographic Area Call (MF/HF) or the 9-digit
identity of the appropriate coast station,
– the 9-digit identity of the ship in distress, if known,
– the nature of distress,
– the latest position of the ship in distress, if known,
– the time (in UTC) the position was valid (if known),
– type of subsequent distress communication (telephony);
– transmit the DSC distress relay call;
– prepare for the subsequent distress traffic by tuning the transmitter and the
radiotelephony receiver to the distress traffic channel in the same band, i.e.
2 182 kHz on MF and channel 16 on VHF, while waiting for the DSC distress
acknowledgement.
Part B – SECTION IV – Rec. ITU-R M.541-9 311
1.5 Acknowledgement of a DSC distress relay call received from a coast
station
Coast stations, after having received and acknowledged a DSC distress alert, may if
necessary, retransmit the information received as a DSC distress relay call, addressed to
all ships (VHF only), all ships in a specific geographical area (MF/HF only), or a
specific ship.
Ships receiving a distress relay call transmitted by a coast station shall not use DSC to
acknowledge the call, but should acknowledge the receipt of the call by radiotelephony
on the distress traffic channel in the same band in which the relay call was received, i.e.
2 182 kHz on MF, channel 16 on VHF.
Acknowledge the receipt of the distress relay call by transmitting the following by
radiotelephony on the distress traffic frequency in the same band in which the DSC
distress relay call was received:
– “MAYDAY” RELAY,
– the 9-digit identity or the call sign or other identification of the calling coast
station,
– “this is”,
– the 9-digit identity or call sign or other identification of own ship,
– “RECEIVED MAYDAY RELAY”.
1.6 Acknowledgement of a DSC distress relay call received from another ship
Ships receiving a distress relay call from another ship shall follow the same procedure
as for acknowledgement of a distress alert, i.e. the procedure given in § 1.2 above.
1.7 Cancellation of an inadvertent distress alert
A station transmitting an inadvertent distress alert shall cancel the distress alert using
the following procedure:
1.7.1 Immediately cancel the distress alert aurally over the telephony distress traffic
channel associated with each DSC channel on which the “distress alert” was
transmitted.
1.7.2 Monitor the telephony distress traffic channel associated with the DSC channel
on which the distress was transmitted, and respond to any communications concerning
that distress alert as appropriate.
312 Maritime Manual
2 Urgency
2.1 Transmission of urgency messages
Transmission of urgency messages shall be carried out in two steps:
– announcement of the urgency message,
– transmission of the urgency message.
The announcement is carried out by transmission of a DSC urgency call on the DSC
distress calling channel (2 187.5 kHz on MF, channel 70 on VHF).
The urgency message is transmitted on the distress traffic channel (2 182 kHz on MF,
channel 16 on VHF).
The DSC urgency call may be addressed to all stations at VHF, or a geographic area at
MF/HF, or to a specific station. The frequency on which the urgency message will be
transmitted shall be included in the DSC urgency call.
The transmission of an urgency message is thus carried out as follows:
Announcement:
– tune the transmitter to the DSC distress calling channel (2 187.5 kHz on MF,
channel 70 on VHF);
– select the appropriate calling format on the DSC equipment (all ships (VHF
only), geographical area (MF/HF only) or individual);
– key in or select on the DSC equipment keyboard:
– specific area or 9-digit identity of the specific station, if appropriate,
– the category of the call (urgency),
– the frequency or channel on which the urgency message will be
transmitted,
– the type of communication in which the urgency message will be given
(radiotelephony),
in accordance with the DSC equipment manufacturer’s instructions;
– transmit the DSC urgency call.
Transmission of the urgency message:
– tune the transmitter to the frequency or channel indicated in the DSC urgency
call;
– transmit the urgency message as follows:
– “PAN PAN”, repeated 3 times,
– “ALL STATIONS” or called station, repeated 3 times,
Part B – SECTION IV – Rec. ITU-R M.541-9 313
– “this is”,
– the 9-digit identity and the call sign or other identification of own ship,
– the text of the urgency message.
2.2 Reception of an urgency message
Ships receiving a DSC urgency call announcing an urgency message addressed to more
than one station shall NOT acknowledge the receipt of the DSC call, but should tune
the radiotelephony receiver to the frequency indicated in the call and listen to the
urgency message.
3 Safety
3.1 Transmission of safety messages
Transmission of safety messages shall be carried out in two steps:
– announcement of the safety message,
– transmission of the safety message.
The announcement is carried out by transmission of a DSC safety call on the DSC
distress calling channel (2 187.5 kHz on MF, channel 70 on VHF).
The safety message is normally transmitted on the distress and safety traffic channel in
the same band in which the DSC call was sent, i.e. 2 182 kHz on MF, channel 16
on VHF.
The DSC safety call may be addressed to all ships (VHF only), ships in a specific
geographical area (MF/HF only), or to a specific station.
The frequency on which the safety message will be transmitted shall be included in the
DSC call.
The transmission of a safety message is thus carried out as follows:
Announcement:
– tune the transmitter to the DSC distress calling channel (2 187.5 kHz on MF,
channel 70 on VHF);
– select the appropriate calling format on the DSC equipment (all ships (VHF
only), geographical area (MF/HF only), or individual);
– key in or select on the DSC equipment keyboard:
– specific area or 9-digit identity of specific station, if appropriate,
– the category of the call (safety),
314 Maritime Manual
– the frequency or channel on which the safety message will be transmitted,
– the type of communication in which the safety message will be given
(radiotelephony),
in accordance with the DSC equipment manufacturer’s instructions;
– transmit the DSC safety call.
Transmission of the safety message:
– tune the transmitter to the frequency or channel indicated in the DSC safety
call;
– transmit the safety message as follows:
– “SECURITE”, repeated 3 times,
– “ALL STATIONS” or called station, repeated 3 times,
– “this is”,
– the 9-digit identity and the call sign or other identification of own ship,
– the text of the safety message.
3.2 Reception of a safety message
Ships receiving a DSC safety call announcing a safety message addressed to more than
one station shall NOT acknowledge the receipt of the DSC safety call, but should tune
the radiotelephony receiver to the frequency indicated in the call and listen to the safety
message.
4 Public correspondence
4.1 DSC channels for public correspondence
4.1.1 VHF
The VHF DSC channel 70 is used for DSC for distress and safety purposes as well as
for DSC for public correspondence.
4.1.2 MF
International and national DSC channels separate from the DSC distress and safety
calling channel 2 187.5 kHz are used for digital selective-calling on MF for public
correspondence.
Ships calling a coast station by DSC on MF for public correspondence should
preferably use the coast station’s national DSC channel.
Part B – SECTION IV – Rec. ITU-R M.541-9 315
The international DSC channel for public correspondence may as a general rule be used
between ships and coast stations of different nationality. The ships transmitting
frequency is 2 189.5 kHz, and the receiving frequency is 2 177 kHz.
The frequency 2 177 kHz is also used for DSC between ships for general
communication.
4.2 Transmission of a DSC call for public correspondence to a coast station or
another ship
A DSC call for public correspondence to a coast station or another ship is transmitted as
follows:
– tune the transmitter to the relevant DSC channel;
– select the format for calling a specific station on the DSC equipment;
– key in or select on the DSC equipment keyboard:
– the 9-digit identity of the station to be called,
– the category of the call (routine),
– the type of the subsequent communication (normally radiotelephony),
– a proposed working channel if calling another ship. A proposal for a
working channel should NOT be included in calls to a coast station; the
coast station will in its DSC acknowledgement indicate a vacant working
channel,
in accordance with the DSC equipment manufacturer’s instructions;
– transmit the DSC call.
4.3 Repeating a call
A DSC call for public correspondence may be repeated on the same or another DSC
channel, if no acknowledgement is received within 5 min.
Further call attempts should be delayed at least 15 min, if acknowledgement is still not
received.
4.4 Acknowledgement of a received call and preparation for reception of the
traffic
On receipt of a DSC call from a coast station or another ship, a DSC acknowledgement
is transmitted as follows:
– tune the transmitter to the transmit frequency of the DSC channel on which the
call was received,
316 Maritime Manual
– select the acknowledgement format on the DSC equipment,
– transmit an acknowledgement indicating whether the ship is able to
communicate as proposed in the call (type of communication and working
frequency),
– if able to communicate as indicated, tune the transmitter and the
radiotelephony receiver to the indicated working channel and prepare to
receive the traffic.
4.5 Reception of acknowledgement and further actions
When receiving an acknowledgement indicating that the called station is able to receive
the traffic, prepare to transmit the traffic as follows:
– tune the transmitter and receiver to the indicated working channel;
– commence the communication on the working channel by:
– the 9-digit identity or call sign or other identification of the called station,
– “this is”,
– the 9-digit identity or call sign or other identification of own ship.
It will normally rest with the ship to call again a little later in case the
acknowledgement from the coast station indicates that the coast station is not able to
receive the traffic immediately.
In case the ship, in response to a call to another ship, receives an acknowledgement
indicating that the other ship is not able to receive the traffic immediately, it will
normally rest with the called ship to transmit a call to the calling ship when ready to
receive the traffic.
5 Testing the equipment used for distress and safety
Testing on the exclusive DSC distress and safety calling frequency 2 187.5 kHz should
be avoided as far as possible by using other methods.
Test calls should be transmitted by the ship station and acknowledged by the called
station. Normally there would be no further communication between the two stations
involved.
A VHF and MF test call to a station is transmitted as follows:
– tune the transmitter to the DSC distress and safety calling frequency (i.e.
channel 70 and 2 187.5 kHz),
Part B – SECTION IV – Rec. ITU-R M.541-9 317
– key in or select the format for the test call on the DSC equipment in
accordance with the DSC equipment manufacturer’s instructions,
– key in the 9-digit identity of the station to be called,
– transmit the DSC call after checking as far as possible that no calls are in
progress on the frequency,
– wait for acknowledgement.
6 Special conditions and procedures for DSC communication on HF
General
The procedures for DSC communication on HF are – with some additions described in
§ 6.1 to 6.3 below – equal to the corresponding procedures for DSC communications on
MF/VHF.
Due regard to the special conditions described in § 6.1 to 6.3 should be given when
making DSC communications on HF.
6.1 Distress
6.1.1 Transmission of DSC distress alert
DSC distress alert should be sent to coast stations – e.g. in A3 and A4 sea areas on HF –
and on MF and/or VHF to other ships in the vicinity.
The DSC distress alert should as far as possible include the ship’s last known position
and the time (in UTC) it was valid. If the position and time is not inserted automatically
from the ship’s navigational equipment, it should be inserted manually.
Ship-to-shore distress alert
Choice of HF band
Propagation characteristics of HF radio waves for the actual season and time of the day
should be taken into account when choosing HF bands for transmission of DSC distress
alert.
As a general rule the DSC distress channel in the 8 MHz maritime band (8 414.5 kHz)
may in many cases be an appropriate first choice.
Transmission of the DSC distress alert in more than one HF band will normally
increase the probability of successful reception of the alert by coast stations.
DSC distress alert may be sent on a number of HF bands in two different ways:
a) either by transmitting the DSC distress alert on one HF band, and waiting a
few minutes for receiving acknowledgement by a coast station;
318 Maritime Manual
if no acknowledgement is received within 3 min, the process is repeated by
transmitting the DSC distress alert on another appropriate HF band etc.;
b) or by transmitting the DSC distress alert at a number of HF bands with no, or
only very short, pauses between the calls, without waiting for
acknowledgement between the calls.
It is recommended to follow procedure a) in all cases, where time permits to do so; this
will make it easier to choose the appropriate HF band for commencement of the
subsequent communication with the coast station on the corresponding distress traffic
channel.
Transmitting the DSC distress alert (see Note 1):
– tune the transmitter to the chosen HF DSC distress channel (4 207.5, 6 312,
8 414.5, 12 577, 16 804.5 kHz) (see Note 2);
– follow the instructions for keying in or selection of relevant information on the
DSC equipment keyboard as described in § 1.1;
– transmit the DSC distress alert.
NOTE 1 – Ship-to-ship distress alert should normally be made on MF and/or VHF, using the
procedures for transmission of DSC distress alert on MF/VHF described in § 1.1.
NOTE 2 – Some maritime HF transmitters shall be tuned to a frequency 1 700 Hz lower than the
DSC frequencies given above in order to transmit the DSC distress alert on the correct
frequency.
In special cases, for example in tropical zones, transmission of DSC distress alert on HF
may, in addition to ship-to-shore alerting, also be useful for ship-to-ship alerting.
6.1.2 Preparation for the subsequent distress traffic
After having transmitted the DSC distress alert on appropriate DSC distress channels
(HF, MF and/or VHF), prepare for the subsequent distress traffic by tuning the
radiocommunication set(s) (HF, MF and/or VHF as appropriate) to the corresponding
distress traffic channel(s).
Where multiple frequency call attempts are transmitted the corresponding distress
traffic frequency should be 8 291 kHz.
If method b) described in § 6.1.1 has been used for transmission of DSC distress alert
on a number of HF bands:
– take into account in which HF band(s) acknowledgement has been
successfully received from a coast station;
Part B – SECTION IV – Rec. ITU-R M.541-9 319
– if acknowledgements have been received on more than one HF band,
commence the transmission of distress traffic on one of these bands, but if no
response is received from a coast station then the other bands should be used
in turn.
The distress traffic frequencies are (see RR Appendix 15, Table 15-1):
HF (kHz):
Telephony 4 125 6 215 8 291 12 290 16 420
Telex 4 177.5 6 268 8 376.5 12 520 16 695
MF (kHz):
Telephony 2 182
Telex 2 174.5
VHF: Channel 16 (156.800 MHz).
6.1.3 Distress traffic
The procedures described in § 1.3 are used when the distress traffic on MF/HF is
carried out by radiotelephony.
The following procedures shall be used in cases where the distress traffic on MF/HF is
carried out by radiotelex:
– The forward error correcting (FEC) mode shall be used;
– all messages shall be preceded by:
– at least one carriage return,
– line feed,
– one letter shift,
– the distress signal MAYDAY;
– The ship in distress should commence the distress telex traffic on the
appropriate distress telex traffic channel as follows:
– carriage return, line feed, letter shift,
– the distress signal “MAYDAY”,
– “this is”,
– the 9-digit identity and call sign or other identification of the ship,
320 Maritime Manual
– the ship’s position if not included in the DSC distress alert,
– the nature of distress,
– any other information which might facilitate the rescue.
6.1.4 Actions on reception of a DSC distress alert on HF from another ship
Ships receiving a DSC distress alert on HF from another ship shall not acknowledge the
alert, but should:
– watch for reception of a DSC distress acknowledgement from a coast station;
– while waiting for reception of a DSC distress acknowledgement from a coast
station:
prepare for reception of the subsequent distress communication by tuning the
HF radiocommunication set (transmitter and receiver) to the relevant distress
traffic channel in the same HF band in which the DSC distress alert was
received, observing the following conditions:
– if radiotelephony mode was indicated in the DSC distress alert, the HF
radiocommunication set should be tuned to the radiotelephony distress
traffic channel in the HF band concerned;
– if telex mode was indicated in the DSC distress alert, the HF
radiocommunication set should be tuned to the radiotelex distress traffic
channel in the HF band concerned. Ships able to do so should additionally
watch the corresponding radiotelephony distress channel;
– if the DSC distress alert was received on more than one HF band, the
radiocommunication set should be tuned to the relevant distress traffic
channel in the HF band considered to be the best one in the actual case. If
the DSC distress alert was received successfully on the 8 MHz band, this
band may in many cases be an appropriate first choice;
– if no distress traffic is received on the HF channel within 1 to 2 min, tune
the HF radiocommunication set to the relevant distress traffic channel in
another HF band deemed appropriate in the actual case;
– if no DSC distress acknowledgement is received from a coast station
within 5 min, and no distress communication is observed going on
between a coast station and the ship in distress:
– inform a Rescue Coordination Centre (RCC) via appropriate
radiocommunications means,
− transmit a DSC distress relay call.
Part B – SECTION IV – Rec. ITU-R M.541-9 321
6.1.5 Transmission of DSC distress relay call
In case it is considered appropriate to transmit a DSC distress relay call:
− distress relay calls on HF should be initiated manually;
– tune the transmitter(s) to the relevant DSC distress channel, following the
procedures described in § 6.1.1 above (except the call is sent manually as a
single call on a single frequency);
– follow the instructions for keying in or selection of call format and relevant
information on the DSC equipment keyboard as described in § 1.4;
– transmit the DSC distress relay call.
6.1.6 Acknowledgement of a HF DSC distress relay call received from a coast
station
Ships receiving a DSC distress relay call from a coast station on HF, addressed to all
ships within a specified area, should NOT acknowledge the receipt of the relay alert by
DSC, but by radiotelephony on the telephony distress traffic channel in the same
band(s) in which the DSC distress relay call was received.
6.2 Urgency
Transmission of urgency messages on HF should normally be addressed:
– either to all ships within a specified geographical area,
– or to a specific coast station.
Announcement of the urgency message is carried out by transmission of a DSC call
with category urgency on the appropriate DSC distress channel.
The transmission of the urgency message itself on HF is carried out by radiotelephony
or radiotelex on the appropriate distress traffic channel in the same band in which the
DSC announcement was transmitted.
6.2.1 Transmission of DSC announcement of an urgency message on HF
– choose the HF band considered to be the most appropriate, taking into account
propagation characteristics for HF radio waves at the actual season and time of
the day; the 8 MHz band may in many cases be an appropriate first choice;
– tune the HF transmitter to the DSC distress channel in the chosen HF band;
– key in or select call format for either geographical area call or individual call
on the DSC equipment, as appropriate;
– in case of area call, key in specification of the relevant geographical area;
322 Maritime Manual
– follow the instructions for keying in or selection of relevant information on the
DSC equipment keyboard as described in § 2.1, including type of
communication in which the urgency message will be transmitted
(radiotelephony or radiotelex);
– transmit the DSC call; and
– if the DSC call is addressed to a specific coast station, wait for DSC
acknowledgement from the coast station. If acknowledgement is not received
within a few minutes, repeat the DSC call on another HF frequency deemed
appropriate.
6.2.2 Transmission of the urgency message and subsequent action
– tune the HF transmitter to the distress traffic channel (telephony or telex)
indicated in the DSC announcement;
– if the urgency message is to be transmitted using radiotelephony, follow the
procedure described in § 2.1;
– if the urgency message is to be transmitted by radiotelex, the following
procedure shall be used:
– use the forward error correcting (FEC) mode unless the message is
addressed to a single station whose radiotelex identity number is known;
– commence the telex message by:
– at least one carriage return, line feed, one letter shift,
– the urgency signal “PAN PAN”,
– “this is”,
– the 9-digit identity of the ship and the call sign or other identification
of the ship,
– the text of the urgency message.
Announcement and transmission of urgency messages addressed to all HF equipped
ships within a specified area may be repeated on a number of HF bands as deemed
appropriate in the actual situation.
6.3 Safety
The procedures for transmission of DSC safety announcement and for transmission of
the safety message are the same as for urgency messages, described in § 6.2, except
that:
– in the DSC announcement, the category SAFETY shall be used,
– in the safety message, the safety signal “SECURITE” shall be used instead of
the urgency signal “PAN PAN”.
Part B – SECTION IV – Rec. ITU-R M.541-9 323
Annex 4
Operational procedures for coast stations for DSC
communications on MF, HF and VHF
Introduction
Procedures for DSC communications on MF and VHF are described in § 1 to 5 below.
The procedures for DSC communications on HF are in general the same as for MF and
VHF. Special conditions to be taken into account when making DSC communications
on HF are described in § 6 below.
1 Distress (see Note 1)
1.1 Reception of a DSC distress alert
The transmission of a distress alert indicates that a mobile unit (a ship, aircraft or other
vehicle) or a person is in distress and requires immediate assistance. The distress alert is
a digital selective call using a distress call format.
Coast stations in receipt of a distress alert shall ensure that it is routed as soon as
possible to an RCC. The receipt of a distress alert is to be acknowledged as soon as
possible by the appropriate coast station.
NOTE 1 – These procedures assume that the RCC is sited remotely from the DSC coast station;
where this is not the case, appropriate amendments should be made locally.
1.2 Acknowledgement of a DSC distress alert
The coast station shall transmit the acknowledgement on the distress calling frequency
on which the call was received and should address it to all ships. The acknowledgement
shall include the identification of the ship whose distress alert is being acknowledged.
The acknowledgement of a DSC distress alert is transmitted as follows:
– use a transmitter which is tuned to the frequency on which the distress alert
was received;
– in accordance with the DSC equipment manufacturer’s instructions, key in or
select on the DSC equipment keyboard (see Note 1):
– distress alert acknowledgement,
– 9-digit identity of the ship in distress,
324 Maritime Manual
– nature of distress,
– distress coordinates,
– the time (in UTC) when the position was valid.
NOTE 1 – Some or all of this information might be included automatically by
the equipment;
– transmit the acknowledgement;
– prepare to handle the subsequent distress traffic by setting watch on
radiotelephony and, if the “mode of subsequent communication” signal in the
received distress alert indicates teleprinter, also on NBDP, if the coast station
is fitted with NBDP. In both cases, the radiotelephone and NBDP frequencies
should be those associated with the frequency on which the distress alert was
received (on MF 2 182 kHz for radiotelephony and 2 174.5 kHz for NBDP, on
VHF 156.8 MHz/channel 16 for radiotelephony; there is no frequency for
NBDP on VHF).
1.3 Transmission of a DSC distress relay call
Coast stations shall initiate and transmit a distress relay call in any of the following
cases:
– when the distress of the mobile unit has been notified to the coast station by
other means and a broadcast alert to shipping is required by the RCC; and
– when the person responsible for the coast station considers that further help is
necessary (close cooperation with the appropriate RCC is recommended under
such conditions).
In the cases mentioned above, the coast station shall transmit a shore-to-ship distress
relay call addressed, as appropriate, to all ships (VHF only), to a geographical area
(MF/HF only) or to a specific ship.
The distress relay call shall contain the identification of the mobile unit in distress, its
position and other information which might facilitate rescue.
The distress relay call is transmitted as follows:
– use a transmitter which is tuned to the frequency for DSC distress alerts
(2 187.5 kHz on MF, 156.525 MHz/channel 70 on VHF);
– in accordance with the DSC equipment manufacturer’s instructions, key in or
select on the DSC equipment keyboard (see Note 1 of § 1.2 of this Annex):
– distress relay call,
– the format specifier (all ships (VHF only), geographical area (MF/HF
only), or individual station),
Part B – SECTION IV – Rec. ITU-R M.541-9 325
– if appropriate, the address of the ship, or geographical area,
– 9-digit identity of the ship in distress, if known,
– nature of distress,
– distress coordinates,
– the time (in UTC) when the position was valid;
– transmit the distress relay call;
– prepare for the reception of the acknowledgements by ship stations and for
handling the subsequent distress traffic by switching over to the distress traffic
channel in the same band, i.e. 2 182 kHz on MF, 156.8 MHz/channel 16
on VHF.
1.4 Reception of a distress relay call
If the distress relay call is received from a ship station, coast stations on receipt of the
distress relay call shall ensure that the call is routed as soon as possible to an RCC. The
receipt of the distress relay call is to be acknowledged as soon as possible by the
appropriate coast station using a DSC distress relay acknowledgement addressed to the
ship station. If the distress relay call is received from a coast station, other coast stations
will normally not have to take further action.
2 Urgency
2.1 Transmission of a DSC announcement
The announcement of the urgency message shall be made on one or more of the distress
and safety calling frequencies using DSC and the urgency call format.
The DSC urgency call may be addressed to all ships (VHF only), to a geographical area
(MF/HF only), or to a specific ship. The frequency on which the urgency message will
be transmitted after the announcement shall be included in the DSC urgency call.
The DSC urgency call is transmitted as follows:
– use a transmitter which is tuned to the frequency for DSC distress calls
(2 187.5 kHz on MF, 156.525 MHz /channel 70 on VHF);
– in accordance with the DSC equipment manufacturer’s instructions, key in or
select on the DSC equipment keyboard (see Note 1 of § 1.2 of this Annex):
– the format specifier (all ships call (VHF), geographical area (MF/HF
only), or individual station),
– if appropriate, the address of the ship, or geographical area,
326 Maritime Manual
– the category of the call (urgency),
– the frequency or channel on which the urgency message will be
transmitted,
– the type of communication in which the urgency message will be
transmitted (radiotelephony);
– transmit the DSC urgency call.
After the DSC announcement, the urgency message will be transmitted on the
frequency indicated in the DSC call.
3 Safety
3.1 Transmission of a DSC announcement
The announcement of the safety message shall be made on one or more of the distress
and safety calling frequencies using DSC and the safety call format.
The DSC safety call may be addressed to all ships (VHF only), to a geographical area
(MF/HF only), or to a specific ship. The frequency on which the safety message will be
transmitted after the announcement shall be included in the DSC safety call.
The DSC safety call is transmitted as follows:
– use a transmitter which is tuned to the frequency for DSC distress alerts
(2 187.5 kHz on MF, 156.525 MHz/channel 70 on VHF);
– in accordance with the DSC equipment manufacturer’s instructions, key in or
select on the DSC equipment keyboard (see Note 1 of § 1.2 of this Annex):
– the format specifier (all ships call (VHF only), geographical area (MF/HF
only), or individual station),
– if appropriate, the address of the ship, or geographical area,
– the category of the call (safety),
– the frequency or channel on which the safety message will be transmitted,
– the type of communication in which the safety message will be
transmitted (radiotelephony);
– transmit the DSC safety call.
After the DSC announcement, the safety message will be transmitted on the frequency
indicated in the DSC call.
Part B – SECTION IV – Rec. ITU-R M.541-9 327
4 Public correspondence
4.1 DSC frequencies/channels for public correspondence
4.1.1 VHF
The frequency 156.525 MHz/channel 70 is used for DSC for distress and safety
purposes. It may also be used for calling purposes other than distress and safety, e.g.
public correspondence.
4.1.2 MF
For public correspondence national and international frequencies are used which are
different from the frequencies used for distress and safety purposes.
When calling ship stations by DSC, coast stations should use for the call, in the order of
preference:
– a national DSC channel on which the coast station is maintaining watch;
– the international DSC calling channel, with the coast station transmitting on
2 177 kHz and receiving on 2 189.5 kHz. In order to reduce interference on this
channel, it may be used as a general rule by coast stations to call ships of
another nationality, or in cases where it is not known on which DSC
frequencies the ship station is maintaining watch.
4.2 Transmission of a DSC call to a ship
The DSC call is transmitted as follows:
– use a transmitter which is tuned to the appropriate calling frequency;
– in accordance with the DSC equipment manufacturer’s instructions, key in or
select on the DSC equipment keyboard (see Note 1 of § 1.2 of this Annex):
– the 9-digit identity of the ship to be called,
– the category of the call routine,
– the type of subsequent communication (radiotelephony),
– working frequency information;
– after checking as far as possible that there are no calls in progress, transmit the
DSC call.
4.3 Repeating a call
Coast stations may transmit the call twice on the same calling frequency with an
interval of at least 45 s between the two calls, provided that they receive no
acknowledgement within that interval.
328 Maritime Manual
If the station called does not acknowledge the call after the second transmission, the call
may be transmitted again on the same frequency after a period of at least 30 min or on
another calling frequency after a period of at least 5 min.
4.4 Preparation for exchange of traffic
On receipt of a DSC acknowledgement with the indication that the called ship station
can use the proposed working frequency, the coast station transfers to the working
frequency or channel and prepares to receive the traffic.
4.5 Acknowledgement of a received DSC call
Acknowledgements shall normally be transmitted on the frequency paired with the
frequency of the received call. If the same call is received on several calling channels,
the most appropriate channel shall be chosen for transmission of the acknowledgement.
The acknowledgement of a DSC call is transmitted as follows:
– use a transmitter which is tuned to the appropriate frequency;
– in accordance with the DSC equipment manufacturer’s instructions, key in or
select on the DSC equipment keyboard (see Note 1 of § 1.2 of this Annex):
– the format specifier (individual station),
– 9-digit identity of the calling ship,
– the category of the call routine,
– if able to comply immediately on the working frequency suggested by the
ship station, the same frequency information as in the received call,
– if no working frequency was suggested by the calling ship station, then
the acknowledgement should include a channel/frequency proposal,
– if not able to comply on the working frequency suggested, but able to
comply immediately on an alternative frequency, the alternative working
frequency,
– if unable to comply immediately the appropriate information in that
regard;
– transmit the acknowledgement (after checking as far as possible that there are
no calls in progress on the frequency selected) after a delay of at least
5 seconds, but not later than 4 ½ minutes.
After having transmitted the acknowledgement, the coast station transfers to the
working frequency or channel and prepares to receive the traffic.
Part B – SECTION IV – Rec. ITU-R M.541-9 329
5 Testing the equipment used for distress and safety calls
Perform VHF, MF and HF test calls in accordance with Recommendation
ITU-R M.493, Table 4.7.
Acknowledgement of a DSC test call
The coast station should acknowledge test calls.
6 Special conditions and procedures for DSC communication on HF
General
The procedures for DSC communication on HF are – with some additions described in
§ 6.1 to 6.3 below – equal to the corresponding procedures for DSC communications on
MF/VHF.
Due regard to the special conditions described in § 6.1 to 6.3 should be given when
making DSC communications on HF.
6.1 Distress
6.1.1 Reception and acknowledgement of a DSC distress alert on HF
Ships in distress may in some cases transmit the DSC distress alert on a number of HF
bands with only short intervals between the individual calls.
The coast station shall transmit DSC acknowledgement on all HF DSC distress
channels on which the DSC distress alert was received in order to ensure as far as
possible that the acknowledgement is received by the ship in distress and by all ships
which received the DSC distress alert.
6.1.2 Distress traffic
The distress traffic should, as a general rule, be initiated on the appropriate distress
traffic channel (radiotelephony or NBDP) in the same band in which the DSC distress
alert was received.
For distress traffic by NBDP the following rules apply:
– all messages shall be preceded by at least one carriage return, line feed, one
letter shift and the distress signal MAYDAY;
– FEC broadcast mode should be used.
330 Maritime Manual
6.1.3 Transmission of DSC distress relay call on HF
HF propagation characteristics should be taken into account when choosing HF band(s)
for transmission of DSC distress relay call.
IMO Convention ships equipped with HF DSC for distress and safety purposes are
required to keep continuous automatic DSC watch on the DSC distress channel in the
8 MHz band and on at least one of the other HF DSC distress channels.
In order to avoid creating on board ships uncertainty regarding on which band the
subsequent establishment of contact and distress traffic should be initiated, the HF DSC
distress relay call should be transmitted on one HF band at a time and the subsequent
communication with responding ships be established before eventually repeating the
DSC distress relay call on another HF band.
6.2 Urgency
6.2.1 Transmission of urgency announcement and message on HF
For urgency messages by NBDP the following apply:
– the urgency message shall be preceded by at least one carriage return, line
feed, one letter shift, the urgency signal PAN PAN and the identification of the
coast station;
– FEC broadcast mode should normally be used.
ARQ mode should be used only when considered advantageous to do so in the
actual situation and provided that the radiotelex number of the ship is known.
6.3 Safety
6.3.1 Transmission of safety announcements and messages on HF
For safety messages by NBDP the following apply:
– the safety message shall be preceded by at least one carriage return, line feed,
one letter shift, the safety signal SECURITE and the identification of the coast
station;
– FEC broadcast mode should normally be used.
ARQ mode should be used only when considered advantageous to do so in the
actual situation and provided that the radiotelex number of the ship is known.
Part B – SECTION IV – Rec. ITU-R M.541-9 331
Annex 5
Frequencies used for DSC
1 The frequencies used for distress, urgency, and safety purposes using DSC are
as follows (RR Appendix 15):
2 187.5 kHz
4 207.5 kHz
6 312 kHz
8 414.5 kHz
12 577 kHz
16 804.5 kHz
156.525 MHz (Note 1)
NOTE 1 – The frequency 156.525 MHz may also be used for DSC purposes other than distress,
urgency, and safety.
2 The frequencies assignable on an international basis to ship and coast stations
for DSC, for purposes other than distress, urgency, and safety, are as follows (see
Note 2):
2.1 Ship stations (see Note 2)
458.5 kHz
2 177 (Note 3) 2 189.5 kHz
4 208 4 208.5 4 209 kHz
6 312.5 6 313 6 313.5 kHz
8 415 8 415.5 8 416 kHz
12 577.5 12 578 12 578.5 kHz
16 805 16 805.5 16 806 kHz
18 898.5 18 899 18 899.5 kHz
22 374.5 22 375 22 375.5 kHz
25 208.5 25 209 25 209.5 kHz
156.525 MHz
332 Maritime Manual
2.2 Coast stations (see Note 2)
455.5 kHz
2 177 kHz
4 219.5 4 220 4 220.5 kHz
6 331 6 331.5 6 332 kHz
8 436.5 8 437 8 437.5 kHz
12 657 12 657.5 12 658 kHz
16 903 16 903.5 16 904 kHz
19 703.5 19 704 19 704.5 kHz
22 444 22 444.5 22 445 kHz
26 121 26 121.5 26 122 kHz
156.525 MHz
NOTE 2 – The following (kHz) paired frequencies (for ship/coast stations) 4 208/4 219.5,
6 312.5/6 331, 8 415/8 436.5, 12 577.5/12 657, 16 805/16 903, 18 898.5/19 703.5, 22 374.5/22 444
and 25 208.5/26 121 are the first choice international frequencies for DSC (See RR Appendix 17,
Part A, footnote j) and l)).
NOTE 3 – The frequency 2 177 kHz is available to ship stations for intership calling only.
3 In addition to the frequencies listed in § 2 above, appropriate working
frequencies in the following bands may be used for DSC (see RR Chapter II, Article 5):
415-526.5 kHz (Regions 1 and 3)
415-525 kHz (Region 2)
1 606.5-3 400 kHz (Regions 1 and 3)
1 605.5-3 400 kHz (Region 2) (For the band 1 605-1 625 kHz, see RR
No. 5.89)
4 000-27 500 kHz
156-174 MHz
Part B – SECTION IV – Rec. ITU-R M.1171 333
RECOMMENDATION ITU-R M.1171*
RADIOTELEPHONY PROCEDURES IN THE
MARITIME MOBILE SERVICE
(1995) Rec. ITU-R M.1171
ANNEX 1
Section I. Introduction
§ 1. Radiotelephone stations should, as far as possible, be equipped with devices for
instantaneous switching from transmission to reception and vice versa. This equipment is
necessary for all stations participating in communication between ships and subscribers of the
land telephone system.
§ 2. (1) Stations equipped for radiotelephony may transmit and receive radiotelegrams by
means of radiotelephony. Coast stations providing such service and open for public
correspondence shall be indicated in the List of Coast Stations.
(2) To facilitate radiocommunications the service abbreviations given in
Recommendation ITU-R M.1172 may be used.
Section II. Calls by Radiotelephony
§ 3. The provisions of this Section relating to the intervals between calls are not applicable
to a station operating under conditions involving distress, urgency or safety.
§ 4. (1) As a general rule, it rests with the ship station to establish communication with
the coast station. For this purpose the ship station may call the coast station only when it comes
within the service area of the latter, that is to say, that area within which, by using an appropriate
frequency, the ship station can be heard by the coast station.
(2) However, a coast station having traffic for a ship station may call this station if it
has reason to believe that the ship station is keeping watch and is within the service area of the
coast station.
_______________
Note by the Secretariat: The references made to the Radio Regulations (RR) in this Recommendation refer
to the RR as revised by the World Radiocommunication Conference 1995. These elements of the RR will
come into force on 1 June 1998. Where applicable, the equivalent references in the current RR are also
provided in square brackets.
334 Maritime Manual
§ 5. (1) In addition, each coast station shall, so far as practicable, transmit its calls in the
form of “traffic lists” consisting of the call signs or other identification in alphabetical order of
all ship stations for which it has traffic on hand. These calls shall be made at specified times
fixed by agreement between the administrations concerned and at intervals of not less than two
hours and not more than four hours during the working hours of the coast station.
(2) Coast stations shall transmit their traffic lists on their normal working frequencies
in the appropriate bands. The transmission shall be preceded by a general call to all stations.
(3) The general call to all stations announcing the traffic lists may be sent on a
calling frequency in the following form:
– “Hello all ships” or CQ (spoken as CHARLIE QUEBEC) not more than three
times;
– the words THIS IS (or DE spoken as DELTA ECHO in case of language
difficulties);
– “ . . . Radio” not more than three times;
– “Listen for my traffic list on . . . kHz”.
In no case may this preamble be repeated.
(4) However, in the bands between 156 MHz and 174 MHz when the conditions for
establishing contact are good, the call described in § 5.(3) above may be replaced by:
– “Hello all ships” or CQ (spoken as CHARLIE QUEBEC), once;
– the words THIS IS (or DE spoken as DELTA ECHO in case of language
difficulties);
– “ . . . Radio”, twice;
– “Listen for my traffic list on channel . . . ”.
In no case may this preamble be repeated.
(5) The provisions of § 5.(3) are obligatory when 2 182 kHz or 156.8 MHz is used.
(6) The hours at which coast stations transmit their traffic lists and the frequencies
and classes of emission which they use for this purpose shall be stated in the List of Coast
Stations.
(7) Ship stations should as far as possible listen to the traffic lists transmitted by coast
stations. On hearing their call sign or other identification in such a list they must reply as soon as
they can do so.
(8) When the traffic cannot be sent immediately, the coast station shall inform each
ship station concerned of the probable time at which working can begin, and also, if necessary,
the frequency and class of emission which will be used.
§ 6. When a coast station receives calls from several ship stations at practically the same
time, it decides the order in which these stations may transmit their traffic. Its decision shall be
based on the priority (see RR No. S53.1 [No. 4441]) of the radiotelegrams or radiotelephone
calls that the ship stations have on hand and on the need for allowing each calling station to clear
the greatest possible number of communications.
Part B – SECTION IV – Rec. ITU-R M.1171 335
§ 7. (1) When a station called does not reply to a call sent three times at intervals of two
minutes, the calling shall cease.
(2) However, when a station called does not reply, the call may be repeated at three-
minute intervals.
(3) In areas where reliable VHF communication with a called coast station is
practicable, the calling ship station may repeat the call as soon as it is ascertained that traffic has
been terminated at the coast station.
(4) In the case of a communication between a station of the maritime mobile service
and an aircraft station, calling may be renewed after an interval of five minutes.
(5) Before renewing the call, the calling station shall ascertain that the station called
is not in communication with another station.
(6) If there is no reason to believe that harmful interference will be caused to other
communications in progress, the provisions of § 7.(4) above are not applicable. In such cases the
call, sent three times at intervals of two minutes, may be repeated after an interval of not less
than three minutes.
(7) However, before renewing the call, the calling station shall ascertain that further
calling is unlikely to cause interference to other communications in progress and that the station
called is not in communication with another station.
(8) Ship stations shall not radiate a carrier wave between calls.
§ 8. When the name and address of the administration or private operating agency
controlling a ship station are not given in the appropriate list of stations or are no longer in
agreement with the particulars given therein, it is the duty of the ship station to furnish as a
matter of regular procedure, to the coast station to which it transmits traffic, all the necessary
information in this respect.
§ 9. (1) The coast station may, by means of the abbreviation TR (spoken as TANGO
ROMEO), ask the ship station to furnish it with the following information:
a) position and, whenever possible, course and speed;
b) next port of call.
(2) The information referred to in § 9.(1) above, preceded by the abbreviation TR,
should be furnished by ship stations, whenever this seems appropriate, without prior request
from the coast station. The provision of this information is authorized only by the master or the
person responsible for the ship.
336 Maritime Manual
Section III. Method of Calling, Reply to Calls and
Signals Preparatory to Traffic when Using Calling
Methods Other than Digital Selective Calling
A. Method of Calling
§ 10. (1) The call consists of:
– the call sign or other identification of the station called, not more than three
times;
– the words THIS IS (or DE spoken as DELTA ECHO in case of language
difficulties);
– the call sign or other identification of the calling station, not more than three
times.
(2) However, in the bands between 156 MHz and 174 MHz when the conditions for
establishing contact are good, the call described in § 10.(1) above may be replaced by:
– the call sign of the station called, once;
– the words THIS IS (or DE spoken as DELTA ECHO in case of language
difficulties);
– the call sign or other identification of the calling station, twice.
(3) When calling a VHF coast station operating on more than one channel, a ship
station calling on a working channel should include the number of that channel in the call.
(4) When contact is established, the call sign or other identification may thereafter be
transmitted once only.
(5) When the coast station is fitted with equipment for selective calling in accordance
with Recommendation ITU-R M.541, and the ship station is fitted with equipment for receiving
such selective calls, the coast station shall call the ship by transmitting the appropriate code
signals. The ship station shall call the coast station by speech in the manner given in § 10.(1)
(see also Annex 2 to Recommendation ITU-R M.257).
§ 11. Calls for internal communications on board ship when in territorial waters shall consist
of:
a) From the master station:
– the name of the ship followed by a single letter (ALFA, BRAVO,
CHARLIE, etc.) indicating the sub-station not more than three times;
– the words THIS IS;
– the name of the ship followed by the word CONTROL;
Part B – SECTION IV – Rec. ITU-R M.1171 337
b) From the sub-station:
– the name of the ship followed by the word CONTROL not more than three
times;
– the words THIS IS;
– the name of the ship followed by a single letter (ALFA, BRAVO,
CHARLIE, etc.) indicating the sub-station.
B. Frequency to Be Used for Calling
and for Preparatory Signals
B1. Bands Between 1 605 kHz and 4 000 kHz
§ 12. (1) A radiotelephone ship station calling a coast station should use for the call, in
order of preference:
a) a working frequency on which the coast station is keeping watch;
b) the carrier frequency 2 182 kHz;
c) in Regions 1 and 3 and in Greenland, the carrier frequency 2 191 kHz (assigned
frequency 2 192.4 kHz) when a carrier frequency of 2 182 kHz is being used for
distress;
d) in Region 2 except for Greenland, the carrier frequency 2 191 kHz as a
supplementary calling frequency in those areas of heavy usage of 2 182 kHz.
(2) A radiotelephone ship station calling another ship station should use for the call:
a) the carrier frequency 2 182 kHz;
b) an intership frequency, whenever and wherever traffic density is high and prior
arrangements can be made.
(3) Subject to the provisions of § 12.(6), coast stations shall, in accordance with the
requirements of their own country, call ship stations of their own nationality either on a working
frequency or, when calls to individual ships are made, on the carrier frequency 2 182 kHz.
(4) However, a ship station which keeps watch simultaneously on the carrier
frequency 2 182 kHz and a working frequency should be called on the working frequency.
(5) As a general rule, coast stations should call radiotelephone ship stations of
another nationality on the carrier frequency 2 182 kHz.
(6) Coast stations may call ship stations equipped to receive selective calls in
accordance with Recommendations ITU-R M.257 and ITU-R M.541.
338 Maritime Manual
B2. Bands Between 4 000 kHz
and 27 500 kHz
§ 13. (1) A ship station calling a coast station by radiotelephony shall use either one of the
calling frequencies mentioned in RR No. S52.221 [No. 4375] or the working frequency
associated with that of the coast station, in accordance with RR Appendix S17, Part B Section I,
[Appendix 16, Section A].
(2) A coast station calling a ship station by radiotelephony shall use one of the calling
frequencies mentioned in RR No. S52.222 [No. 4376], one of its working frequencies shown in
the List of Coast Stations, or the carrier frequency 4 125 kHz or 6 215 kHz, in accordance with
the provisions of RR Nos. S52.221.2 and S52.221.3 [Nos. 4375.2 and 4375.3].
(3) The preliminary operations for the establishment of radiotelephone
communications may also be carried out by radiotelegraphy using the procedure appropriate to
radiotelegraphy (see Recommendation ITU-R M.1170 § 17).
(4) The provisions of § 13.(1) and § 13.(2) do not apply to communications between
ship stations and coast stations using the simplex frequencies specified in RR Appendix S17,
Part B, Section I [Appendix 16, Section B].
B3. Bands Between 156 MHz and 174 MHz
§ 14. (1) In the bands between 156 MHz and 174 MHz, intership and coast station to ship
calling should, as a general rule, be made on 156.8 MHz. However, coast station to ship calling
may be conducted on a working channel or on a two-frequency calling channel which has been
implemented in accordance with RR No. S52.236 [No. 4391]. Except for distress, urgency or
safety communications, when 156.8 MHz should be used, ship to coast station calling should,
whenever possible, be made on a working channel or on a two-frequency calling channel which
has been implemented in accordance with RR No. S52.236 [No. 4391]. Ships wishing to
participate in a port operations service or ship movement service should call on a port operations
or ship movement working frequency, indicated in heavy type in the List of Coast Stations.
(2) When 156.8 MHz is being used for distress, urgency or safety communications, a
ship station desiring to participate in the port operations service may establish contact on
156.6 MHz, or another port operations frequency indicated in heavy type in the List of Coast
Stations.
B4. Procedure for Calling a Station
Providing Pilot Service
§ 15. A radiotelephone ship station calling a station providing pilot service should use for
the call, in order of preference:
a) an appropriate channel in the bands between 156 MHz and 174 MHz;
b) a working frequency in the bands between 1 605 kHz and 4 000 kHz;
c) the carrier frequency 2 182 kHz, and then only to determine the working
frequency to be used.
Part B – SECTION IV – Rec. ITU-R M.1171 339
C. Form of Reply to Calls
§ 16. The reply to calls consists of:
– the call sign or other identification of the calling station, not more than three
times;
– the words THIS IS (or DE spoken as DELTA ECHO in case of language
difficulties);
– the call sign or other identification of the station called, not more than three times.
D. Frequency for Reply
D1. Bands Between 1 605 kHz and 4 000 kHz
§ 17. (1) When a ship station is called on the carrier frequency 2 182 kHz, it should reply
on the same carrier frequency unless another frequency is indicated by the calling station.
(2) When a ship station is called by selective calling in accordance with
Recommendation ITU-R M.257 it shall reply on a frequency on which the coast station keeps
watch.
(3) When a ship station is called on a working frequency by a coast station of the
same nationality, it shall reply on the working frequency normally associated with the frequency
used by the coast station for the call.
(4) When calling a coast station or another ship station, a ship station shall indicate
the frequency on which a reply is required if this frequency is not the normal one associated with
the frequency used for the call.
(5) A ship station which frequently exchanges traffic with a coast station of another
nationality may use the same procedure for reply as ships of the nationality of the coast station,
where this has been agreed by the administrations concerned.
(6) As a general rule a coast station shall reply:
a) on the carrier frequency 2 182 kHz to calls made on the carrier frequency
2 182 kHz, unless another frequency is indicated by the calling station;
b) on a working frequency to calls made on a working frequency;
c) on a working frequency to calls made in Regions 1 and 3 and in Greenland on the
carrier frequency 2 191 kHz (assigned frequency 2 192.4 kHz).
340 Maritime Manual
D2. Bands Between 4 000 kHz
and 27 500 kHz
§ 18. (1) A ship station called by a coast station shall reply either on one of the calling
frequencies mentioned in RR No. S52.221 [No. 4375] or on the working frequency associated
with that of the coast station, in accordance with RR Appendix S17, Part B, Section I
[Appendix 16, Section A].
(2) A coast station called by a ship station shall reply on one of the calling
frequencies mentioned in RR No. S52.222 [No. 4376], or on one of its working frequencies
shown in the List of Coast Stations.
(3) When a station is called on the carrier frequency 4 125 kHz it should reply on the
same frequency unless another frequency is indicated for that purpose by the calling station.
(4) When a station is called on the carrier frequency 6 215 kHz it should reply on the
same frequency unless another frequency is indicated for that purpose by the calling station.
(5) The provisions of § 18.(1) and § 18.(2) do not apply to communication between
ship stations and coast stations using the simplex frequencies specified in RR Appendix S17,
Part B, Section I [Appendix 16, Section B].
D3. Bands Between 156 MHz and 174 MHz
§ 19. (1) When a station is called on 156.8 MHz it should reply on the same frequency
unless another frequency is indicated by the calling station.
(2) When a coast station open to public correspondence calls a ship either by speech
or by selective calling in accordance with Annex 2 to Recommendation ITU-R M.257, using a
two-frequency channel, the ship station shall reply by speech on the frequency associated with
that of the coast station; conversely, a coast station shall reply to a call from a ship station on the
frequency associated with that of the ship station.
E. Indication of the Frequency to Be Used for Traffic
E1. Bands Between 1 605 kHz and 4 000 kHz
§ 20. If contact is established on the carrier frequency 2 182 kHz, coast and ship stations
shall transfer to working frequencies for the exchange of traffic.
E2. Bands Between 4 000 kHz
and 27 500 kHz
§ 21. After a ship station has established contact with a coast station, or another ship station,
on the calling frequency of the band chosen, traffic shall be exchanged on their respective
working frequencies.
Part B – SECTION IV – Rec. ITU-R M.1171 341
E3. Bands Between 156 MHz and 174 MHz
§ 22. (1) Whenever contact has been established between a coast station in the public
correspondence service and a ship station either on 156.8 MHz or on a two-frequency calling
channel (see RR No. S52.237 [No. 4392]), the stations shall transfer to one of their normal pairs
of working frequencies for the exchange of traffic. The calling station should indicate the
channel to which it is proposed to transfer by reference to the frequency in MHz or, preferably,
to its channel designator.
(2) When contact on 156.8 MHz has been established between a coast station in the
port operations service and a ship station, the ship station should indicate the particular service
required (such as navigational information, docking instructions, etc.) and the coast station shall
then indicate the channel to be used for the exchange of traffic by reference to the frequency in
MHz, or, preferably, to its channel designator.
(3) When contact on 156.8 MHz has been established between a coast station in the
ship movement service and a ship station, the coast station shall then indicate the channel to be
used for the exchange of traffic by reference to the frequency in MHz or, preferably, to its
channel designator.
(4) A ship station, when it has established contact with another ship station on
156.8 MHz, should indicate the intership channel to which it is proposed to transfer for the
exchange of traffic by reference to the frequency in MHz or, preferably, to its channel
designator.
(5) However, a brief exchange of traffic not to exceed one minute concerning the
safety of navigation need not be transmitted on a working frequency when it is important that all
ships within range receive the transmission.
(6) Stations hearing a transmission concerning the safety of navigation shall listen to
the message until they are satisfied that the message is of no concern to them. They shall not
make any transmission likely to interfere with the message.
F. Agreement on the Frequency to Be Used for Traffic
§ 23. (1) If the station called is in agreement with the calling station, it shall transmit:
a) an indication that from that moment onwards it will listen on the working
frequency or channel announced by the calling station;
b) an indication that it is ready to receive the traffic of the calling station.
(2) If the station called is not in agreement with the calling station on the working
frequency or channel to be used, it shall transmit an indication of the working frequency or
channel proposed.
(3) For communications between a coast station and a ship station, the coast station
shall finally decide the frequency or channel to be used.
(4) When agreement is reached regarding the working frequency or channel which
the calling station shall use for its traffic, the station called shall indicate that it is ready to
receive the traffic.
342 Maritime Manual
G. Indication of Traffic
§ 24. When the calling station wishes to exchange more than one radiotelephone call, or to
transmit one or more radiotelegrams, it should indicate this when contact is established with the
station called.
H. Difficulties in Reception
§ 25. (1) If the station called is unable to accept traffic immediately, it should reply to the
call as indicated in § 16 followed by “Wait . . . minutes” (or SA spoken as ALFA SIERRA . . .
(minutes) in case of language difficulties), indicating the probable duration of waiting time in
minutes. If the probable duration exceeds ten minutes the reason for the delay shall be given.
Alternatively the station called may indicate, by any appropriate means, that it is not ready to
receive traffic immediately.
(2) When a station receives a call without being certain that such a call is intended
for it, it shall not reply until the call has been repeated and understood.
(3) When a station receives a call which is intended for it, but is uncertain of the
identification of the calling station, it shall reply immediately asking for a repetition of the call
sign or other identification of the calling station.
Section IV. Forwarding (Routing) of Traffic
A. Traffic Frequency
§ 26. (1) Every station should transmit its traffic (radiotelephone calls or radiotelegrams)
on one of its working frequencies in the band in which the call has been made.
(2) In addition to its normal working frequency, printed in heavy type in the List of
Coast Stations, a coast station may use one or more supplementary frequencies in the same band,
in accordance with the provisions of RR Article S52 [Article 60].
(3) The use of frequencies reserved for calling shall be forbidden for traffic, except
distress traffic (see RR Appendix S13 [Chapter IX]).
(4) After contact has been established on the frequency to be used for traffic, the
transmission of a radiotelegram or radiotelephone call shall be preceded by:
– the call sign or other identification of the station called;
– the words THIS IS (or DE spoken as DELTA ECHO in case of language
difficulties);
– the call sign or other identification of the calling station.
(5) The call sign or other identification need not be sent more than once.
Part B – SECTION IV – Rec. ITU-R M.1171 343
B. Establishment of Radiotelephone Calls
and Transmission of Radiotelegrams
B1. Establishment of Radiotelephone Calls
§ 27. (1) In setting up a radiotelephone call, the coast station should establish connection
with the telephone network as quickly as possible. In the meantime, the ship station shall
maintain watch on the appropriate working frequency as indicated by the coast station.
(2) However, if the connection cannot be quickly established, the coast station shall
inform the ship station accordingly. The latter station shall then either:
a) maintain watch on the appropriate frequency until an effective circuit can be
established; or
b) contact the coast station later at a mutually agreed time.
(3) When a radiotelephone call has been completed, the procedure indicated in
§ 29.(3) shall be applied unless further calls are on hand at either station.
B2. Transmission of Radiotelegrams
§ 28. (1) The transmission of a radiotelegram should be made as follows:
– radiotelegram begins: from . . . (name of ship or aircraft);
– number . . . (serial number of radiotelegram);
– number of words . . . ;
– date . . . ;
– time . . . (time radiotelegram was handed in aboard ship or aircraft);
– service indicators (if any);
– address . . . ;
– text . . . ;
– signature . . . (if any);
– radiotelegram ends, over.
(2) As a general rule, radiotelegrams of all kinds transmitted by ship stations shall be
numbered in a daily series; number 1 shall be given to the first radiotelegram sent each day to
each separate station.
(3) A series of numbers which has begun in radiotelegraphy should be continued in
radiotelephony and vice versa.
(4) Each radiotelegram should be transmitted once only by the sending station.
However, it may, when necessary, be repeated in full or in part by the receiving or the sending
station.
344 Maritime Manual
(5) In transmitting groups of figures, each figure shall be spoken separately and the
transmission of each group or series of groups shall be preceded by the words “in figures”.
(6) Numbers written in letters shall be spoken as they are written, their transmission
being preceded by the words “in letters”.
B3. Acknowledgement of Receipt
§ 29. (1) The acknowledgement of receipt of a radiotelegram or a series of radiotelegrams
shall be given by the receiving station in the following manner:
– the call sign or other identification of the sending station;
– the words THIS IS (or DE spoken as DELTA ECHO in case of language
difficulties);
– the call sign or other identification of the receiving station;
– “Your No. . . . received, over” (or R spoken as ROMEO . . . (number), K spoken
as KILO in case of language difficulties); or
` – “Your No. . . . to No. . . . received, over” (or R spoken as ROMEO . . . (numbers),
K spoken as KILO in case of language difficulties).
(2) The radiotelegram, or series of radiotelegrams, shall not be considered as cleared
until this acknowledgement has been received.
(3) The end of work between two stations shall be indicated by each of them by
means of the word “Out” (or VA spoken as VICTOR ALFA in case of language difficulties).
Section V. Duration and Control of Working
§ 30. (1) In communications between coast stations and ship stations, the ship station shall
comply with the instructions given by the coast station in all questions relating to the order and
time of transmission, to the choice of frequency, and to the duration and suspension of work.
(2) In communications between ship stations, the station called controls the working
in the manner indicated in § 30.(1) above. However, if a coast station finds it necessary to
intervene, the ship stations shall comply with the instructions given by the coast station.
Part B – SECTION IV – Rec. ITU-R M.1173 345
RECOMMENDATION ITU-R M.1173*
TECHNICAL CHARACTERISTICS OF SINGLE-SIDEBAND TRANSMITTERS
USED IN THE MARITIME MOBILE SERVICE FOR RADIOTELEPHONY IN
THE BANDS BETWEEN 1 606.5 kHz (1 605 kHz REGION 2) AND 4 000 kHz
AND BETWEEN 4 000 kHz AND 27 500 kHz
(1995)
Rec. ITU-R M.1173
ANNEX 1
Technical characteristics of single-sideband transmitters used in
the maritime mobile service for radiotelephony in the bands
between 1606.5 kHz (1 605 kHz Region 2) and 4 000 kHz
and between 4000 kHz and 27 500 kHz
1 Power of the carrier:
For class J3E emissions the power of the carrier shall be at least 40 dB below the peak
envelope power.
2 Coast and ship stations shall use only the upper sideband.
3 The transmitter audio-frequency band shall be 350 Hz to 2 700 Hz with a permitted
amplitude variation of 6 dB.
4 The carrier frequencies shall be maintained within the tolerances specified in
Recommendation ITU-R SM.1137.
5 The unwanted frequency modulation of the carrier shall be sufficiently low to prevent
harmful distortion.
_______________
Note by the Secretariat: The references made to the Radio Regulations (RR) in this Recommendation refer
to the RR as revised by the World Radiocommunication Conference 1995. These elements of the RR will
come into force on 1 June 1998. Where applicable, the equivalent references in the current RR are also
provided in square brackets.
346 Maritime Manual
6 When class H3E or J3E emissions are used, the power of any unwanted emission
supplied to the antenna transmission line on any discrete frequency shall, when the transmitter is
driven to full peak envelope power, be in accordance with the following Tables:
a) Transmitters installed before 2 January 1982:
Transmitters using suppressed carrier emission may, as far as concerns out-of-band
emissions 2 and those spurious emissions 3 which are a result of the modulation process but do
not fall in the spectrum of out-of-band emissions 2, be tested for compliance with this regulation
by means of a two-tone-audio input signal with a frequency separation between the tones such
that all intermodulation products occur at frequencies at least 1.6 kHz removed from the
assigned frequency 4.
b) Transmitters installed after 1 January 1982:
Transmitters using suppressed carrier emission may, as far as concerns out-of-band
emissions 2 and those spurious emissions 3 which are a result of the modulation process but do
not fall in the spectrum of out-of-band emissions 2, be tested for compliance with this regulation
by means of a two-tone-audio input signal with a frequency separation between the tones such
that all intermodulation products occur at frequencies at least 1.5 kHz removed from the
assigned frequency 4.
_______________
1 Unwanted emission: see RR No. S1.146 [No. 140].
2 Out-of-band emission: see RR No. S1.144 [No. 138].
3 Spurious emission: see RR No. S1.145 [No. 139].
4 The assigned frequency is 1 400 Hz higher than the carrier frequency: see RR No. S.52.177 [No. 4325].
Separation ∆ between the frequency of the unwanted emission 1
and the assigned frequency 4
(kHz)
Minimum attenuation below peak envelope power
1.6 < ∆ ≤ 4.8 28 dB
4.8 < ∆ ≤ 8 38 dB
8 < ∆ 43 dB without the unwanted emission power exceeding the power of 50 mW
Separation ∆ between the frequency of the unwanted emission 1
and the assigned frequency 4
(kHz)
Minimum attenuation below peak envelope power
1.5 < ∆ ≤ 4.5 31 dB
4.5 < ∆ ≤ 7.5 38 dB
7.5 < ∆ 43 dB without the unwanted emission power exceeding the power of 50 mW
Part B – SECTION IV – Rec. ITU-R M.1174-2 347
RECOMMENDATION ITU-R M.1174-2
Technical characteristics of equipment used for on-board
vessel communications in the bands
between 450 and 470 MHz
(1995-1998-2004)
Annex 1
Technical characteristics of equipment used for on-board
vessel communications in the bands
between 450 and 470 MHz
1 The equipment should be fitted with sufficient channels for satisfactory
operation in the area of intended use.
2 The effective radiated power should be limited to the maximum required for
satisfactory operations, but should in no case exceed 2 W. Wherever practicable the
equipment should be fitted with a suitable device to reduce readily the output power by
at least 10 dB.
3 In the case of equipment installed at a fixed point on the ship, the height of its
antenna should not be more than 3.5 m above the level of the bridge.
348 Maritime Manual
25 kHz channels 12.5 kHz channels
4 Only frequency modulation with a
pre-emphasis of 6 dB/octave (phase
modulation) should be used.
Only frequency modulation with a
pre-emphasis of 6 dB/octave (phase
modulation) should be used.
5 The frequency deviation
corresponding to 100% modulation
should approach ± 5 kHz as nearly
as practicable. In no event should
the frequency deviation exceed
± 5 kHz.
The frequency deviation corresponding
to 100% modulation should approach
± 2.5 kHz as nearly as practicable. In no
event should the frequency deviation
exceed ± 2.5 kHz.
6 The frequency tolerance should be
5 parts in 106.
The frequency tolerance should be
2.5 parts in 106.
7 The audio-frequency band should
be limited to 3 000 Hz.
The audio-frequency band should be
limited to 2 550 Hz.
8 Control, telemetry and other non-voice signals such as paging, should be
coded in such a manner as to minimize the possibility of false response to interfering
signals. The frequencies specified in RR No. 5.287 for on-board communications may
be used for single frequency and two-frequency simplex operation.
9 When used in the duplex mode the base transmitter frequency should be
selected from the lower range for improved operability.
10 If the use of a repeater station is required on board a ship, the following
frequency pairs should be used (see RR No. 5.287 and 5.288):
457.525 MHz and 467.525 MHz
457.550 MHz and 467.550 MHz
457.575 MHz and 467.575 MHz
457.5375 MHz and 467.5375 MHz
457.5625 MHz and 467.5625 MHz.
Part B – SECTION IV – Rec. ITU-R M.1174-2 349
11 Frequencies
The frequencies specified in RR No. 5.287 (subject to national regulations) may be
used:
For 25 or 12.5 kHz channel spacing:
457.525 MHz
457.550 MHz
457.575 MHz
467.525 MHz
467.550 MHz
467.575 MHz.
For equipment designed to operate with 12.5 kHz channel spacing the additional
frequencies referred to in RR No. 5.287 are:
457.5375 MHz
457.5625 MHz
467.5375 MHz
467.5625 MHz.
_______________
PART C
Extracts from other ITU-R
Recommendations
(M and SM Series)
Part C – Rec. ITU-R M.493-13 353
RECOMMENDATION ITU-R M.493-13
Digital selective-calling system for use
in the maritime mobile service
(1974-1978-1982-1986-1990-1992-1994-1995-1997-1997-2000-2004-2007-2009)
Annex 1
General purpose equipment characteristics
1 General
1.1 The system is a synchronous system using characters composed from a ten-bit
error-detecting code as listed in Table 1.
1.1.1 The first seven bits of the ten-bit code of Table 1 are information bits. Bits 8, 9
and 10 indicate, in the form of a binary number, the number of B elements that occur
in the seven information bits, a Y element being a binary number 1 and a B element
a binary number 0. For example, a BYY sequence for bits 8, 9 and 10 indicates
3 (0 × 4 + 1 × 2 + 1 × 1) B elements in the associated seven information bit sequence;
and a YYB sequence indicates 6 (1 × 4 + 1 × 2 + 0 × 1) B elements in the associated
seven information bit sequence. The order of transmission for the information bits is
least significant bit first but for the check bits it is most significant bit first.
1.2 Time diversity is provided in the call sequence as follows:
1.2.1 Apart from the phasing characters, each character is transmitted twice in a
time-spread mode; the first transmission (DX) of a specific character is followed by the
transmission of four other characters before the re-transmission (RX) of that specific
character takes place, allowing for a time-diversity reception interval of:
1.2.1.1 400 ms for HF and MF channels, and
1.2.1.2 331/3 ms for VHF radio-telephone channels.
1.3 The classes of emission, frequency shifts and modulation rates are as follows:
1.3.1 F1B or J2B 170 Hz and modulation rate of 100 Bs (bit/s) ± 30 × 106 for use on
HF and MF DSC calling channels. When frequency-shift keying is effected by applying
audio signals to the input of single-sideband transmitters (J2B), the centre of the audio-
frequency spectrum offered to the transmitter is 1 700 Hz. When a DSC call is
354 Maritime Manual
transmitted on HF and MF working channels for public correspondence, the class of
emission is J2B. In this case, audio tones with frequencies 1 700 Hz ± 85 Hz and
modulation rate 100 Bs (bit/s) ± 30 × 106 are used in order for the DSC call to be
transmitted.
1.3.2 Frequency modulation with a pre-emphasis of 6 dB/octave (phase modulation)
with frequency-shift of the modulating sub-carrier for use on VHF channels:
– frequency-shift between 1 300 and 2 100 Hz; the sub-carrier being at 1 700 Hz;
– the frequency tolerance of the 1 300 and 2 100 Hz tones is ± 10 Hz;
– the modulation rate is 1 200 B s (bit/s) ± 30 × 106;
– the index of modulation is 2.0 ± 10%.
1.3.3 The radio-frequency tolerances of new designs of both transmitters and
receivers in the MF and HF bands should be:
– coast station: ± 10 Hz,
– ship station: ± 10 Hz,
– receiver bandwidth: should not exceed 300 Hz.
1.4 The higher frequency corresponds to the B-state and the lower frequency
corresponds to the Y-state of the signal elements.
1.5 The information in the call is presented as a sequence of seven-bit
combinations constituting a primary code.
1.5.1 The seven information bits of the primary code express a symbol number
from 00 to 127, as shown in Table 1, and where:
1.5.1.1 the symbols from 00 to 99 are used to code two decimal figures according to
Table 2;
1.5.1.2 the symbols from 100 to 127 are used to code service commands (see Table 3).
1.6 Where the distress alert repetitions described in § 11 apply, the following
conditions are considered necessary:
1.6.1 the transmitter encoder must provide repetitive transmission of the call
sequence in accordance with § 11; and
1.6.2 the receiver decoder should provide maximum utilization of the received
signal, including use of the error-check character and by using an iterative decoding
process with adequate memory provision.
1.7 When the transmission of a DSC distress alert is automatically repeated, ships’
DSC equipments must be capable of automatically receiving a subsequent distress
acknowledgement (see Recommendation ITU-R M.541, Annex 1, § 3.1.3.1, 3.1.3.2
and 3.3.5).
Part C – Rec. ITU-R M.493-13 355
TABLE 1
Ten-bit error-detecting code
Symbol
No.
Emitted signal
and bit position
1 2 3 4 5 6 7 8 9 10
Symbol
No.
Emitted signal
and bit position
1 2 3 4 5 6 7 8 9 10
Symbol
No.
Emitted signal
and bit position
1 2 3 4 5 6 7 8 9 10
00
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
BBBBBBBYYY
YBBBBBBYYB
BYBBBBBYYB
YYBBBBBYBY
BBYBBBBYYB
YBYBBBBYBY
BYYBBBBYBY
YYYBBBBYBB
BBBYBBBYYB
YBBYBBBYBY
BYBYBBBYBY
YYBYBBBYBB
BBYYBBBYBY
YBYYBBBYBB
BYYYBBBYBB
YYYYBBBBYY
BBBBYBBYYB
YBBBYBBYBY
BYBBYBBYBY
YYBBYBBYBB
BBYBYBBYBY
YBYBYBBYBB
BYYBYBBYBB
YYYBYBBBYY
BBBYYBBYBY
YBBYYBBYBB
BYBYYBBYBB
YYBYYBBBYY
BBYYYBBYBB
YBYYYBBBYY
BYYYYBBBYY
YYYYYBBBYB
BBBBBYBYYB
YBBBBYBYBY
BYBBBYBYBY
YYBBBYBYBB
BBYBBYBYBY
YBYBBYBYBB
BYYBBYBYBB
YYYBBYBBYY
BBBYBYBYBY
YBBYBYBYBB
BYBYBYBYBB
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
YYBYBYBBYY
BBYYBYBYBB
YBYYBYBBYY
BYYYBYBBYY
YYYYBYBBYB
BBBBYYBYBY
YBBBYYBYBB
BYBBYYBYBB
YYBBYYBBYY
BBYBYYBYBB
YBYBYYBBYY
BYYBYYBBYY
YYYBYYBBYB
BBBYYYBYBB
YBBYYYBBYY
BYBYYYBBYY
YYBYYYBBYB
BBYYYYBBYY
YBYYYYBBYB
BYYYYYBBYB
YYYYYYBBBY
BBBBBBYYYB
YBBBBBYYBY
BYBBBBYYBY
YYBBBBYYBB
BBYBBBYYBY
YBYBBBYYBB
BYYBBBYYBB
YYYBBBYBYY
BBBYBBYYBY
YBBYBBYYBB
BYBYBBYYBB
YYBYBBYBYY
BBYYBBYYBB
YBYYBBYBYY
BYYYBBYBYY
YYYYBBYBYB
BBBBYBYYBY
YBBBYBYYBB
BYBBYBYYBB
YYBBYBYBYY
BBYBYBYYBB
YBYBYBYBYY
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
BYYBYBYBYY
YYYBYBYBYB
BBBYYBYYBB
YBBYYBYBYY
BYBYYBYBYY
YYBYYBYBYB
BBYYYBYBYY
YBYYYBYBYB
BYYYYBYBYB
YYYYYBYBBY
BBBBBYYYBY
YBBBBYYYBB
BYBBBYYYBB
YYBBBYYBYY
BBYBBYYYBB
YBYBBYYBYY
BYYBBYYBYY
YYYBBYYBYB
BBBYBYYYBB
YBBYBYYBYY
BYBYBYYBYY
YYBYBYYBYB
BBYYBYYBYY
YBYYBYYBYB
BYYYBYYBYB
YYYYBYYBBY
BBBBYYYYBB
YBBBYYYBYY
BYBBYYYBYY
YYBBYYYBYB
BBYBYYYBYY
YBYBYYYBYB
BYYBYYYBYB
YYYBYYYBBY
BBBYYYYBYY
YBBYYYYBYB
BYBYYYYBYB
YYBYYYYBBY
BBYYYYYBYB
YBYYYYYBBY
BYYYYYYBBY
YYYYYYYBBB
B = 0
Y = 1 Order of bit transmission: bit 1 first.
356 Maritime Manual
TABLE 2
Packing table for decimal numbers into ten-bit characters
TABLE 3
Use of symbol Nos. 100 to 127
The digits for the
Thousands
of millions
D2
Hundreds
of millions
D1
Tens of
millions
D2
Millions
D1
Hundreds of
thousands
D2
Tens of
thousands
D1
Thousands
D2
Hundreds
D1
Tens
D2
Units
D1
Character 5 Character 4 Character 3 Character 2 Character 1
NOTE 1 – Character 1 is the last character transmitted.
The digit sequence D2-D1 varies from 00 to 99 inclusive in each character (character 1 to 5 inclusive). The character that
represents a particular two-decimal figure is transmitted as the symbol number (see Table 1) that is identical to that particular
two-decimal figure.
When the number consists of an odd number of decimal digits, a zero shall be added in front of the most significant position
to provide an integral number of ten-bit characters.
Symbol
No.
Phasing
and unique
functions
Format specifier(1) Category(1) Nature of
distress(1)
First
telecommand(1)
Second
telecommand(1)
100 Routine Fire,
explosion
F3E/G3E
All modes TP
No reason given(2)
101 Flooding F3E/G3E
duplex TP
Congestion at
maritime switching
centre
102 Geographical
area
Collision Busy(2)
103 (3) (3) Grounding Polling Queue indication(2)
104 Phasing
RX-0
position
Listing, in
danger of
capsizing
Unable to
comply
Station barred(2)
105 Phasing
RX-1
position
Sinking End of call(4) No operator
available(2)
106 Phasing
RX-2
position
(6) Disabled and
adrift
Data Operator temporarily
unavailable(2)
107 Phasing
RX-3
position
Undesignated
distress
Equipment disabled(2)
108 Phasing
RX-4
position
Safety Abandoning
ship
Unable to use
proposed channel(2)
Part C – Rec. ITU-R M.493-13 357
TABLE 3 (cont.)
Symbol
No.
Phasing
and unique
functions
Format specifier(1) Category(1) Nature of
distress(1)
First
telecommand(1)
Second
telecommand(1)
109 Phasing
RX-5
position
Piracy/armed
robbery attack
J3E TP Unable to use
proposed mode(2)
110 Phasing
RX-6
position
(5) Urgency Man
overboard
Distress
acknowledgeme
nt
Ships and aircraft of
States not parties to an
armed conflict
111 Phasing
RX-7
position
(6) Medical transports
(as defined in 1949
Geneva Conventions
and additional
Protocols)
112 Distress Distress EPIRB
emission
Distress relay Pay-phone/public call
office
113 F1B/J2B
TTY-FEC
Facsimile/data
according to
Recommendation
ITU-R M.1081
114 Ships having
common interest
115 F1B/J2B
TTY-ARQ
(6)
116 All ships(7) (6) (6)
117 Ack. RQ
(EOS)
(6) (6)
118 Test (6)
119 (6) (6)
120 Individual stations (6) (6)
121 Reserved for
national
non-calling
purposes e.g.
Report
ITU-R M.1159
Ship position
or location
registration
updating
(6)
122 Ack. BQ
(EOS)
(6) (6)
123 Individual station
semi-automatic/
automatic service
(6) (6)
124 (5) (6) (6)
358 Maritime Manual
TABLE 3 (end)
2 Technical format of a call sequence
2.1 The technical format of the call sequence is:
0493-00
Dot patternSee § 3
Phasing sequenceSee § 3
Call contentSee Tables 4.1 to 4.10.2
Closing sequenceSee § 9, § 10 and Fig. 1
2.2 Examples of typical call sequences and the construction of the transmission
format are given in Figs. 1 to 3.
2.3 The flow charts illustrating the operation of the DSC system are shown in
Figs. 4 and 5.
3 Dot pattern and phasing
3.1 The phasing sequence provides information to the receiver to permit correct bit
phasing and unambiguous determination of the positions of the characters within a call
sequence (see Note 1).
Symbol
No.
Phasing
and unique
functions
Format specifier(1) Category(1) Nature of
distress(1)
First
telecommand(1)
Second
telecommand(1)
125 Phasing
DX
position
(6) (6)
126 * No information No information
127 EOS (6) (6)
TP: Telephony
TTY: Direct printing
ARQ: Rec. ITU-R M.476 or Rec. ITU-R M.625 equipment
(1) Unassigned symbols should be rejected. The DSC equipment should take no action.
(2) Currently unassigned when used with first telecommands other than symbol No. 104 – for future use.
(3) Used for selective call to a group of ships in a specified VTS area (Rec. ITU-R M.825). Reception of calls having
format specifier 103, for (or) category shall not activate any alarms on shipborne DSC controller. Should not be used
in any future expansion.
(4) Only used for semi-automatic/automatic service.
(5) Used in the automatic VHF/UHF service (Rec. ITU-R M.586). Should not be used in any future expansion.
(6) Should not be used in any future expansion.
(7) MF/HF used only for distress alert acknowledgment and coast station receive (see Table 4).
Part C – Rec. ITU-R M.493-13 359
NOTE 1 – Acquisition of character synchronization should be achieved by means of character
recognition rather than, for example, by recognizing a change in the dot pattern, in order to
reduce false synchronization caused by a bit error in the dot pattern.
3.2 The phasing sequence consists of specific characters in the DX and RX
positions transmitted alternatively. Six DX characters are transmitted.
3.2.1 The phasing character in the DX position is symbol No. 125 of Table 1.
3.2.2 The phasing characters in the RX position specify the start of the information
sequence (i.e. the format specifier) and consist of the symbol Nos. 111, 110, 109, 108,
107, 106, 105 and 104 of Table 1, consecutively.
3.3 Phasing is considered to be achieved when two DXs and one RX, or two RXs
and one DX, or three RXs in the appropriate DX or RX positions, respectively, are
successfully received. These three phasing characters may be detected in either
consecutive or non-consecutive positions but in both cases all bits of the phasing
sequence should be examined for a correct 3-character pattern. A call should be rejected
only if a correct pattern is not found anywhere within the phasing sequence.
3.4 To provide appropriate conditions for earlier bit synchronization and to allow
for scanning methods to monitor several HF and MF frequencies by ship stations, the
phasing sequence should be preceded by a dot pattern (i.e. alternating B-Y or Y-B
sequence bit synchronization signals) with duration of:
3.4.1 200 bits
At HF and MF for:
– distress alerts;
– distress acknowledgements;
– distress relays addressed to a geographic area;
– distress relay acknowledgements addressed to all ships;
– all calls addressed to a ship station other than those specified in § 3.4.2.
3.4.2 20 bits
At HF and MF, for all acknowledgements to individual calls having format specifiers
120 and 123 and for all calling to coast stations. At VHF for all calls.
4 Format specifier
4.1 The format specifier characters which are transmitted twice in both the DX
and RX positions (see Fig. 1) are:
4.1.1 symbol No. 112 for a “distress” alert; or
4.1.2 symbol No. 116 for an “all ships” call; or
360 Maritime Manual
4.1.3 symbol No. 114 for a selective call to a group of ships having a common
interest (e.g. belonging to one particular country, or to a single ship owner, etc.); or
4.1.4 symbol No. 120 for a selective call to a particular individual station; or
4.1.5 symbol No. 102 for a selective call to a group of ships in a particular
geographic area; or
4.1.6 symbol No. 123 for a selective call to a particular individual station using the
semi-automatic/automatic service.
4.2 It is considered that receiver decoders must detect the format specifier
character twice for “distress” alerts and “all ships” calls to effectively eliminate false
alerting. For other calls, the address characters provide additional protection against
false alerting and, therefore, single detection of the format specifier character is
considered satisfactory (see Table 3).
5 Address
5.1 “Distress” alerts and “all ships” calls do not have addresses since these calls
are implicitly addressed to all stations (ship stations and coast stations).
5.2 For a selective call directed to an individual ship, to a coast station or to a
group of stations having a common interest, the address consists of the characters
corresponding to the station’s maritime mobile service identity, the sequence consisting
of characters coded in accordance with Table 2 (see Note 1).
NOTE 1 – According to RR Article 19, maritime mobile service identities are formed of a series
of nine digits, consisting of three digits of the Maritime Identification Digits (MID) and six more
digits.
These identities are included in the address and self-identification parts of the call sequence and
are transmitted as five characters C5C4C3C2C1, comprising the ten digits of:
(X1, X2) (X3, X4) (X5, X6) (X7, X8) and (X9, X10)
respectively, whereas digit X10 is always the figure 0 unless the equipment is also designed in
accordance with Recommendation ITU-R M.1080.
Example:
MID X4 X5 X6 X7 X8 X9 being the ship station identity is transmitted by the DSC equipment as:
(M, I) (D, X4) (X5, X6) (X7, X8) (X9, 0)
5.3 For a selective call directed to a group of ships in a particular geographic area
a numerical geographic coordinates address consisting of ten digits (i.e. 5 characters), is
constructed as follows (see Fig. 6 and Note 1):
Part C – Rec. ITU-R M.493-13 361
NOTE 1 – In order to comply with commonly accepted practice, the order of entry and read-out
should be: first latitude and then longitude.
5.3.1 the designated geographic area will be a rectangle in Mercator projection;
5.3.2 the upper left-hand (i.e. North-West) corner of the rectangle is the reference
point for the area;
5.3.3 the first digit indicates the azimuth sector in which the reference point is
located, as follows:
5.3.3.1 quadrant NE is indicated by the digit “0”,
5.3.3.2 quadrant NW is indicated by the digit “1”,
5.3.3.3 quadrant SE is indicated by the digit “2”,
5.3.3.4 quadrant SW is indicated by the digit “3”;
5.3.4 the second and third digits indicate the latitude of the reference point in tens
and units of degrees;
5.3.5 the fourth, fifth and sixth digits indicate the longitude of the reference point in
hundreds, tens and units of degrees;
5.3.6 the seventh and eighth digits indicate the vertical (i.e. North-to-South) side of
the rectangle, ∆ϕ, in tens and units of degrees;
5.3.7 the ninth and tenth digits indicate the horizontal (i.e. West-to-East) side of the
rectangle, ∆λ, in tens and units of degrees.
6 Category
6.1 The “category” information is coded as shown in Table 3 and defines the
degree of priority of the call sequence.
6.2 For a “distress” alert the priority is defined by the format specifier and no
category information is included in the call sequence.
6.2.1 For distress relays, distress relay acknowledgements and distress
acknowledgements the category is distress.
6.3 For safety related calls, the “category” information specifies:
6.3.1 urgency; or
6.3.2 safety.
6.4 For other calls, the “category” information specifies:
6.4.1 routine.
362 Maritime Manual
7 Self-identification
7.1 The maritime mobile service identity (MMSI) assigned to the calling station,
coded as indicated in § 5.2 and its Note 1, is used for self-identification.
8 Messages
The messages that are included in a call sequence contain the following message
elements, which are listed in the order in which they would appear in each message. All
message formats are explicitly defined in Tables 4.1 through 4.10.2:
8.1 For a “distress” alert (see Table 4.1) the distress information is contained in
four messages in the following order:
8.1.1 Message 1 is the “nature of distress” message, coded as shown in Table 3, i.e.:
8.1.1.1 fire, explosion;
8.1.1.2 flooding;
8.1.1.3 collision;
8.1.1.4 grounding;
8.1.1.5 listing, in danger of capsizing;
8.1.1.6 sinking;
8.1.1.7 disabled and adrift;
8.1.1.8 undesignated distress;
8.1.1.9 abandoning ship;
8.1.1.10 piracy/armed robbery attack;
8.1.1.11 man overboard;
8.1.1.12 emergency position-indicating radiobeacon (EPIRB) emission.
8.1.2 Message 2 is the “distress coordinates” message, consisting of ten digits
indicating the location of the vessel in distress, coded on the principles described in
Table 2, in pairs starting from the first and second digits (see Note 1 to § 5.3):
8.1.2.1 The first digit indicates the quadrant in which the incident has occurred, as
follows:
8.1.2.1.1 quadrant NE is indicated by the digit “0”,
8.1.2.1.2 quadrant NW is indicated by the digit “1”,
8.1.2.1.3 quadrant SE is indicated by the digit “2”,
8.1.2.1.4 quadrant SW is indicated by the digit “3”.
Part C – Rec. ITU-R M.493-13 363
8.1.2.2 The next four figures indicate the latitude in degrees and minutes.
8.1.2.3 The next five figures indicate the longitude in degrees and minutes.
8.1.2.4 If “distress coordinates” cannot be included, or if the position information has
not been updated for 23½ h, the 10 digits following the “nature of distress” should be
automatically transmitted as the digit 9 repeated 10 times.
8.1.3 Message 3 is the time indication (UTC) when the coordinates were valid
consisting of four digits coded on the principles described in Table 2, in pairs starting
from the first and second digits.
8.1.3.1 The first two digits indicate the time in hours.
8.1.3.2 The third and fourth digits indicate the part of the hours in minutes.
8.1.3.3 If the time cannot be included the four time indicating digits should be
transmitted automatically as “8 8 8 8”.
8.1.4 Message 4 is a single character to indicate the type of communication
(telephone or FEC teleprinter) which is preferred by the station in distress for
subsequent exchange of distress traffic. This character is coded as shown in Table 3
first telecommand.
8.2 For a distress relay, distress relay acknowledgement, distress
acknowledgement (see Tables 4.2, 4.3 and 4.4) the distress information is contained in
five messages in the following order:
8.2.1 Message 0 is the “MMSI” of the vessel in distress.
8.2.2 Message 1 is the “nature of distress” message, coded as shown in Table 3, i.e.:
8.2.2.1 fire, explosion;
8.2.2.2 flooding;
8.2.2.3 collision;
8.2.2.4 grounding;
8.2.2.5 listing, in danger of capsizing;
8.2.2.6 sinking;
8.2.2.7 disabled and adrift;
8.2.2.8 undesignated distress;
8.2.2.9 abandoning ship;
8.2.2.10 piracy/armed robbery attack;
8.2.2.11 man overboard;
8.2.2.12 emergency position-indicating radiobeacon (EPIRB) emission.
364 Maritime Manual
8.2.3 Message 2 is the “distress coordinates” message, consisting of ten digits
indicating the location of the vessel in distress, coded on the principles described in
Table 2, in pairs starting from the first and second digits (see Note 1 to § 5.3):
8.2.3.1 The first digit indicates the quadrant in which the incident has occurred, as
follows:
8.2.3.1.1 quadrant NE is indicated by the digit “0”,
8.2.3.1.2 quadrant NW is indicated by the digit “1”,
8.2.3.1.3 quadrant SE is indicated by the digit “2”,
8.2.3.1.4 quadrant SW is indicated by the digit “3”.
8.2.3.2 The next four figures indicate the latitude in degrees and minutes.
8.2.3.3 The next five figures indicate the longitude in degrees and minutes.
8.2.3.4 If “distress coordinates” cannot be included, or if the position information has
not been updated for 23½ h, the 10 digits following the “nature of distress” should be
automatically transmitted as the digit 9 repeated 10 times.
8.2.4 Message 3 is the time indication (UTC) when the coordinates were valid
consisting of four digits coded on the principles described in Table 2, in pairs starting
from the first and second digits.
8.2.4.1 The first two digits indicate the time in hours.
8.2.4.2 The third and fourth digits indicate the part of the hours in minutes.
8.2.4.3 If the time cannot be included the four time indicating digits should be
transmitted automatically as “8 8 8 8”.
8.2.5 Message 4 is a single character to indicate the type of communication
(telephone or FEC teleprinter) which is preferred by the station in distress for
subsequent exchange of distress traffic. This character is coded as shown in Table 3
first telecommand.
8.3 For other types of calls (see Table 4.5 through 4.10.2 and Figs. 2 and 3)
messages are included in the following order:
8.3.1 Message 1 is the “telecommand” information and consists of 2 characters (first
and second telecommand) coded as shown in Table 3;
8.3.1.1 if no information additional to that conveyed by the first telecommand
character is required, then the second telecommand signal should be symbol No. 126
(no information) (see Table 3);
8.3.1.2 if no telecommand information is used, symbol No. 126 is transmitted twice.
Part C – Rec. ITU-R M.493-13 365
8.3.1.3 If the telecommand 1 is “F3E/G3E duplex TP” (symbol 101) in a request,
which can be complied with, the telecommand 1 “F3E/G3E all modes TP”
(symbol 100) should be used in the acknowledgement.
8.3.2 Message 2 may contain two “channel or frequency message” elements, each of
which always consists of three characters, “character 1”, “character 2” and “character
3”, indicating the proposed working frequency (in the F1B/J2B mode the assigned
frequency should be used) in multiples of 100 Hz or the channel number (coded in
accordance with Table 5) or the ship’s position. The first frequency element (the RX
field) in the call indicates the called station receive frequency and the second frequency
element (the TX field) indicates the called station transmit frequency. In
acknowledgements the RX and TX fields indicate the receive and transmit frequency of
the acknowledging station respectively (see also Fig. 2 and Note 1).
NOTE 1 – If only one channel or frequency message element is used, this indicates the called
station receive channel or frequency or a two-frequency (paired) channel. A second channel or
frequency message element may be used to designate the called station transmit channel or
frequency. If the calling station indicates only the called station receive frequency (for broadcast
mode transmissions) then the symbol No. 126 repeated three times should be transmitted instead
of the called station transmit channel or frequency message element. If no “channel or frequency
message” elements are used, the symbol No. 126 is transmitted six times. For calls using the
semi-automatic/automatic VHF service (see Table 4.10.1) then only one “channel or frequency
message” element is transmitted which indicates the paired channel number. In the absence of
this element the symbol No. 126 should be transmitted three times.
8.3.2.1 Frequency information
The frequency (in the F1B/J2B mode the assigned frequency should be used) in
multiples of 100 Hz may only be indicated as such when the frequency is below
30 MHz. The three characters provide for the required six decimal digits. Character 1
represents the units (U) and tens (T) of 100 Hz, character 2 the hundreds (H) and
thousands (M) and character 3 the tens of thousands (TM) and hundreds of thousands
(HM) of 100 Hz. For MF/HF DSC, use frequency selection mode, vice channel
selection mode, to ensure international interoperability.
8.3.2.2 Channel information
8.3.2.2.1 HF and MF channels
If the HM digit is 3, this indicates that the number represented by the digits TM, M, H,
T and U is the HF/MF working channel number (either single frequency or two
frequency channels). This mode should only be used for decoding received calls, to
ensure interoperability with older equipment.
366 Maritime Manual
8.3.2.2.2 VHF channels
If the HM digit is 9, this indicates that the number represented by the values of the
digits M, H, T and U is the VHF working channel number. If the M digit is 1, this
indicates that the ship stations transmitting frequency is being used as a simplex
channel frequency for both ship and coast stations. If the M digit is 2, this indicates that
the coast stations transmitting frequency is being used as a simplex channel frequency
for both ship and coast stations.
8.3.2.3 Ship’s position information
8.3.2.3.1 For MF/HF calls, Message 2 may contain the ship’s position, consisting of
the digit 5 repeated two times and ten digits (five characters) indicating this position,
coded in accordance with § 8.1.2 to § 8.1.2.3 (see Table 6).
8.3.2.3.2 For position requests message 2 consists of 6 no information symbols
(symbol No. 126).
8.3.2.3.3 In acknowledgements to a call requesting ship’s position (see Fig. 3d))
message 2 consists of twelve digits (six symbols), the first of which should be coded in
accordance with § 8.1.2 to § 8.1.2.3 followed by one symbol No. 126.
Message 3 follows message 2 in this case and contains the time (UTC) when the
coordinates were valid, coded as indicated in § 8.1.3 to § 8.1.3.3.
8.3.3 Message 3 follows message 2 when using the DSC system for calls initiated by
ship stations requiring a semi-automatic or automatic connection (see Table 4.10.1 and
4.10.2) and contains the public switched network number (e.g. telephone number). In
this case the format specifier used is symbol No. 123.
8.3.3.1 This number is coded by up to nine symbols in a manner similar to that shown
in Table 2, except that the first character transmitted should be either symbol No. 105 or
No. 106 to indicate whether the network number contains an odd or even number of
significant digits. As an example, the number 0012345 would be coded as symbol
numbers 105 00 01 23 45 whereas the number 00123456 should be coded as symbol
numbers 106 00 12 34 56.
8.4 For “distress relay” including shore-to-ship alerts, “distress relay
acknowledgement” and “distress acknowledgement” calls, the message formats are
indicated in Tables 4.3, 4.4 and 4.2 respectively.
8.4.1 When sending a distress alert on behalf of another ship which is unable to send
its own alert, and where the identity of the station in distress is unknown, the distress
relay call should contain the symbol No. 126 transmitted five times for the
“identification of the station in distress”.
Part C – Rec. ITU-R M.493-13 367
8.5 Test calls
Test calls on the distress and safety frequencies for MF and HF and VHF channel 70
may be conducted using the test call sequence in Table 4.7.
9 End of sequence
The “end of sequence” (EOS) character is transmitted three times in the DX position
and once in the RX position (see Fig. 1b)). It is one of the three unique characters
corresponding to symbol Nos. 117, 122 and 127 as follows:
9.1 symbol No. 117 if the call requires acknowledgement (Acknowledge RQ),
used for individual and automatic/semiautomatic calls only;
9.2 symbol No. 122 if the sequence is an answer to a call that requires
acknowledgement (Acknowledge BQ), used for individual and automatic/
semiautomatic calls and all distress relay acknowledgements;
9.3 symbol No. 127 for all other calls.
10 Error-check character
10.1 The error-check character (ECC) is the final character transmitted and it serves
to check the entire sequence for the presence of errors which are undetected by the ten-
unit error-detecting code and the time diversity employed.
10.2 The seven information bits of the ECC shall be equal to the least significant bit
of the modulo-2 sums of the corresponding bits of all information characters (i.e. even
vertical parity). The format specifier and the EOS characters are considered to be
information characters. The phasing characters and the retransmission (RX) characters
shall not be considered to be information characters. Only one format specifier
character and one EOS character should be used in constructing the ECC. The ECC
shall also be sent in the DX and RX positions.
10.3 Automatic acknowledgement transmissions should not start unless the ECC is
received and decoded correctly. A received ECC which does not match that calculated
from the received information characters may be ignored if this was due to an error
detected in the ten-unit error-detecting code of the information characters which was
correctable by use of the time diversity code.
10.4 The receiver decoder should provide maximum utilization of the received
signal, including use of the error-check character.
368 Maritime Manual
11 Distress alert attempt
11.1 Distress alerts may be transmitted as a single frequency or a multi-frequency
call attempt preceded by a dot pattern. MF/HF equipment should be capable of using
both single and multi-frequency call attempts. Where a distress alert attempt contains
more than one consecutive distress alert on the same frequency (see Recommendation
ITU-R M.541, Annex 1, § 3.1.3), these consecutive alerts should be transmitted with no
gap between the end of one call and the start of the dot pattern of the following call to
enable bit synchronization to be maintained (see Fig. 1c)). Multi-frequency call
attempts should always include at least the MF and HF 8 MHz band DSC distress and
safety frequencies.
11.2 A distress alert should be activated only by means of a dedicated distress
button which should be clearly identified and be protected against inadvertent operation
with a spring loaded lid or cover. The initiation of a distress alert should at least require
two independent actions.
11.3 Calls with format specifier “distress” or category “distress”, “urgency” and
“safety” should be initiated manually only. This applies also for ships equipped for
automatic DSC operation. For automatic repetition of distress alerts see
Recommendation ITU-R M.541, Annex 1, § 3.1.3 and 3.3.5.
11.4 Immediately following a distress alert a DSC expansion message giving
enhanced position resolution according to Recommendation ITU-R M.821 should be
transmitted in the following manner.
11.4.1 For a single frequency distress alert attempt the expansion message should be
transmitted immediately after the last of five consecutive distress alerts.
11.4.2 For a multi-frequency distress alert attempt the expansion message should be
transmitted immediately after each distress alert.
12 Shipborne human machine interface (HMI)
12.1 Shipborne aural alarm
Shipborne alarms should start softly and increase in volume if not silenced by the
operator. This will give the operator the opportunity to acknowledge the alarm without
interrupting the ship’s current communications. It should be possible for the operator to
disable all audible alarms except those of distress, priority and urgency.
Distress and urgency calls should have a distinctive two tone alarm. The alarm should
consist of two substantially sinusoidal audio-frequency tones, transmitted alternately.
One tone should have a frequency of 2 200 Hz and the other a frequency of 1 300 Hz.
The duration of each tone should be 250 ms.
Part C – Rec. ITU-R M.493-13 369
Distress calls and urgency calls should activate an alarm. For HF and MF distress calls,
the alarm should activate only when a distress alert, distress acknowledgement, or a
distress relay is received and the distress position is within 500 nm (926 km) of the
receiving vessel’s position, or if the distress position is in the polar areas (latitude
greater than 70° N or 70° S). The alarm should also activate when the call is received
and the distance between the vessel in distress and the receiving vessel cannot be
determined.
NOTE 1 – Disabling of aural alarm does not affect handling of call.
For geographic area calls, the alarm appropriate to the category should activate when
the receiving station’s position is within the area specified by the call or the receiving
station’s position is not known. The alarm should not be activated where duplicate
distress relay calls are received within one hour. A duplicate distress relay call is one
having format specifier all ships or geographic area that contains identical message
information, as defined in § 8.1 and an identical distress MMSI.
12.2 Inactivity timer
During normal operation, the equipment should include an inactivity timer to return the
DSC system display to default or standby mode if the operator is in a menu where DSC
call reception is disabled and does not make any selections or changes for 10 min.
12.3 Display
The information on the display should be visible in all shipboard lighting conditions. It
should have the means to display, in plain language, the information contained in the
received call. For Class A/B DSC equipment, the display should have a minimum of
160 characters in two or more lines.
12.4 MMSI
DSC equipment should not transmit any DSC call until own ship’s MMSI allocated to
the ship by the relevant administration has been configured and stored in the DSC
equipment. Once stored, it should not be possible for the user to change the MMSI
without advice from the manufacturer.
The DSC equipment should display own ship’s MMSI on start-up unless the MMSI has
not been configured. If the MMSI has not been configured, the equipment will display a
warning that the unit will not transmit any DSC calls until own ship’s MMSI is entered.
The equipment should stay in this state until the operator confirms he has read the
display and input own ship’s MMSI.
The MMSI should be readily displayed on the HMI when the DSC equipment is on.
370 Maritime Manual
12.5 Disabling of DSC automatic channel switching function on VHF
Automatic switching to a subsequent communications channel on receipt of a DSC call
might in some cases disrupt important ongoing communications. Where such capability
exists, a means for disabling that function should therefore be provided for all calls
other than individual station calls of category distress or urgency. The DSC equipment
should provide visual indication that the automatic switching function is disabled.
12.6 Data interface
DSC equipment should be provided with facilities for exchange of data from shipborne
navigational equipment or systems, or other shipborne equipment as necessary in
accordance with IEC 61162 for purposes including automatic position updating.
12.7 Position updating
DSC equipment should accept valid IEC 61162 position information including the time
at which the position was determined, from an external source utilizing the data
interface described in § 12.6, for automatic update of own ship’s DSC position.
The DSC equipment may also be provided with an internal electronic position fixing
device. In which case, the DSC equipment should automatically switch to the internal
source if the external IEC 61162 position information is not valid or not available.
If the automatic position update is not available, a displayed and audible reminder to
manually update the position should occur before the position information is 4 h old.
The displayed reminder should remain until position updating has been carried out. Any
position information not updated for more than 23½ h should automatically be erased.
Own ship’s DSC position information and the source of that information (external,
internal, or manually entered) should be displayed on the DSC equipment.
12.8 Geographic area entry
DSC equipment should be provided with means for transforming a geographical area
specified by the user as a centre point and a range to the corresponding Mercator area
call format specified in § 5.3. The centre point should default to the ships position
information and the range should default to 500 nm (926 km). The transformation of the
entered range and centre-point should result in the minimum rectangular area that
encompasses the entered data.
12.9 Medical transport and neutral ships and aircraft
The capability of using second telecommands “Ships and aircraft of States not parties to
an armed conflict” and “Medical Transports” should not be available by default but
only after changing relevant parameters in the setup menu.
Part C – Rec. ITU-R M.493-13 371
049
3-0
1
G2
G3
HI
HH
DX
DX
DX
DX
DX
DX
AA
B1
B2
B3
F3
G1
G2
G3
HI
RX
RX
RX
RX
RX
RX
RX
RX
AA
76
54
32
10
G1
F2
DX
DX
DX
DX
DX
DX
AA
B1
B2
B3
B4
B5
CD
1D
2D
3D
4D
5E
1E
2F
1F
2F
3G
1G
2G
3H
IH
H
RX
RX
RX
RX
RX
RX
RX
AA
B1
B2
B3
B4
B5
67
54
32
10
CD
1D
2D
3D
4D
5E
1E
2F
1F
2F
3G
1G
2G
3H
IR
X
DX
/RX
AB
CD
EF
GH
I
FIG
UR
E 1
Con
stru
ctio
n o
f call
seq
uen
ce
Do
t p
atte
rn
c)
Tra
nsm
issi
on s
equ
ence
for
rep
eti
tio
n o
f a d
istr
ess
cal
l ac
cord
ing t
o §
11
b)
Tra
nsm
issi
on s
equ
ence
corr
espo
ndin
g t
o F
ig.
1a)
Do
t p
atte
rn
Do
t
pat
tern
Phasi
ng
seq
uen
ceF
orm
at s
peci
fier
2 i
denti
cal
char
acte
rs
Cal
led p
art
y
add
ress
5 c
hara
cter
s
Cat
ego
ry
1 c
har
acte
r
Sel
f-
identi
fica
tio
n
5 c
har
act
ers
Tel
ecom
man
d
mess
age
2 c
hara
cter
s
Fre
qu
ency
mess
age
3 c
har
act
ers
Fre
qu
ency
mess
age
3 c
har
act
ers
End
of
seq
uen
ce
3 i
denti
cal
DX
chara
cte
rs1
RX
chara
cter
1 c
hara
cter
Err
or-
check
chara
cter
a)
Tech
nic
al
form
at o
f a
typic
al
routi
ne
mes
sage
372 Maritime Manual
049
3-0
2
FIG
UR
E 2
Exam
ple
s of
a c
all
ing s
equ
ence
an
d r
eply
seq
uen
ces
for t
yp
ical
ind
ivid
ual
call
s
Dot
pat
tern
Form
at s
pec
ifie
r2 i
den
tica
lch
arac
ters
Addre
ss5 c
har
acte
rsC
ateg
ory
1 c
har
acte
r
Sel
f-id
enti
fica
tion
5 c
har
acte
rs
Tel
ecom
man
dan
d f
requen
cy
8 c
har
acte
rs
Tel
ecom
man
dan
d f
requen
cy
8 c
har
acte
rs
Ack
now
ledge
RQ
(E
OS
)
3 i
den
tica
l D
X c
har
acte
rs1 R
X c
har
acte
r
Err
or-
chec
k
char
acte
r1
char
acte
r
Phas
ing
sequen
ce
a) C
alli
ng
seq
uen
ce
b)
Rep
ly s
equen
ce w
ith
confi
rmat
ion
c) R
eply
seq
uen
ce w
ith n
ew p
roposa
l
d)
Rep
ly s
equen
ce w
ith r
efusa
l
Dot
pat
tern
Phas
ing
sequen
ce
Form
at s
pec
ifie
r2 i
den
tica
l
char
acte
rs
Addre
ss5 c
har
acte
rsC
ateg
ory
1 c
har
acte
r
Sel
f-id
enti
fica
tion
5 c
har
acte
rs
Ack
now
led
ge
BQ
(E
OS
)
3 i
den
tica
l D
X c
har
acte
rs1 R
X c
har
acte
r
Err
or-
chec
k
char
acte
r1 c
har
acte
r
Err
or-
chec
kch
arac
ter
1 c
har
acte
r
Ack
now
ledge
BQ
(E
OS
)
3 i
den
tica
l D
X c
har
acte
rs1 R
X c
har
acte
r
Ack
now
ledge
BQ
(E
OS
)3 i
den
tica
l D
X c
har
acte
rs
1 R
X c
har
acte
r
Tel
ecom
man
d
and f
requen
cy8 c
har
acte
rs
Tel
ecom
man
dan
d f
requen
cy8 c
har
acte
rs
Cat
egory
1 c
har
acte
r
Cat
egory
1 c
har
acte
r
Sel
f-id
enti
fica
tion
5 c
har
acte
rs
Sel
f-id
enti
fica
tion
5 c
har
acte
rs
Dot
pat
tern
Dot
pat
tern
Phas
ing
sequen
ce
Phas
ing
sequen
ce
Form
at s
pec
ifie
r
2 i
den
tica
lch
arac
ters
Form
at s
pec
ifie
r
2 i
den
tica
lch
arac
ters
Addre
ss5 c
har
acte
rs
Addre
ss5 c
har
acte
rs
Err
or-
chec
kch
arac
ter
1 c
har
acte
r
Part C – Rec. ITU-R M.493-13 373
049
3-0
3
FIG
UR
E
3
Ca
llin
g s
eq
uen
ces
an
d r
ep
ly s
equ
ences
fo
r p
oll
ing a
nd
sh
ip’s
posi
tion
Dot
pat
tern
Form
at s
pec
ifie
r2
id
enti
cal
char
acte
rs
Ad
dre
ss
5 c
har
acte
rsC
ateg
ory
1 c
har
acte
r
Sel
f-id
enti
fica
tion
5 c
har
acte
rsT
elec
om
man
d p
oll
ing
2 c
har
acte
rs
Ack
no
wle
dg
e R
Q (
EO
S)
3 i
den
tica
l D
X c
har
acte
rs1
RX
ch
arac
ter
Err
or-
chec
kch
arac
ter
1 c
har
acte
r
Phas
ing
seq
uen
ce
a)
Cal
lin
g s
equen
ce p
oll
ing
b)
Rep
ly s
equ
ence
to
poll
ing
c)
Cal
lin
g s
equen
ce t
o r
equ
est
ship
’s p
osi
tio
n
d)
Rep
ly s
equen
ce t
o r
equ
est
for
ship
’s p
osi
tion
Do
t
pat
tern
Phas
ing
seq
uen
ce
Form
at s
pec
ifie
r2
id
enti
cal
char
acte
rs
Add
ress
5 c
har
acte
rs
Cat
ego
ry
1 c
har
acte
r
Sel
f-id
enti
fica
tion
5 c
har
acte
rs
Ack
no
wle
dg
e B
Q (
EO
S)
3 i
den
tica
l D
X c
har
acte
rs1
RX
ch
arac
ter
Err
or-
chec
k
char
acte
r1
ch
arac
ter
Err
or-
chec
kch
arac
ter
1 c
har
acte
r
Ack
now
led
ge
RQ
(E
OS
)
3 i
den
tica
l D
X c
har
acte
rs1
RX
ch
arac
ter
Ack
no
wle
dg
e B
Q (
EO
S)
3 i
den
tica
l D
X c
har
acte
rs
1 R
X c
har
acte
r
Tel
eco
mm
and
ship
’s p
osi
tio
n2 c
har
acte
rs
Cat
ego
ry1
ch
arac
ter
Cat
ego
ry1
ch
arac
ter
Sel
f-id
enti
fica
tion
5 c
har
acte
rs
Sel
f-id
enti
fica
tion
5 c
har
acte
rs
Do
t p
atte
rn
Do
t
pat
tern
Phas
ing
seq
uen
ce
Phas
ing
sequ
ence
Form
at s
pec
ifie
r
2 i
den
tica
lch
arac
ters
Fo
rmat
spec
ifie
r2
id
enti
cal
char
acte
rs
Ad
dre
ss5
ch
arac
ters
Ad
dre
ss5
ch
arac
ters
Err
or-
chec
k
char
acte
r1
char
acte
r
Tel
ecom
man
d p
oll
ing
2 c
har
acte
rs* 6c* 6c
* 6c C
oo
rdin
ates
**
6 c
har
acte
rs
**
*
Tim
e2
c
Tel
eco
mm
and
ship
’s p
osi
tio
n
2 c
har
acte
rs
*
T
he
sym
bo
l N
o. 1
26
rep
eate
d s
ix t
imes
sh
ou
ld b
e in
clud
ed (
see
§ 8
.3.2
, N
ote
1).
**
See
§ 8
.3.2
.3.3
(6
ch
arac
ters
).*
**
See
§ 8
.3.2
.3.2
(2
ch
arac
ters
).
374 Maritime Manual
0493-04
FIGURE 4
Example of operational flow chartTransmitting
Messagecomposition*
Transmitmessage
Receiving
Operation in general
No (Yes)
Yes (No)
Branching (decision)
Manual operation
Beginning or endof the procedures
This method may be used when either single channel receivers(without scanning) or multi-channel receivers are used.
This method is preferable when scanning receivers are usedon DSC channels.
Message composition flow chart is shown in Fig. 5b.
AcknowledgeBQ
AcknowledgeRQ
Scanning?
Addresserror free?
Addresscorresponds to astored address?
Receive and processmessage
Store messageReceivemessage
Messagereceived error
free?
Addresscorresponds to astored address?
No
Yes
Yes
ReceivedECC
matches?
IndicateECC error
No
Read informationof received
message
Yes
Yes (2)
No
No
Safetyrelated?
End ofsequence
Yes
Proceduresas given in RR
No
Messagecomposition
Messagecomposition with
unableto comply
Messagecomposition with
acknowledgeBQ
Transmitmessage
End
Wait on workingfrequency/
channel
Able tocomply?
Allacceptable?
No
Yes Message composition*
Yes
Yes
Messagecomposition with
new proposal
No(1)
*
(1)
(2)
No
Yes
No
Note – This chart is informative only.
Part C – Rec. ITU-R M.493-13 375
0493-05
FIGURE 5
Example of message composition flow chart
Distress
Area GroupSpecial
sequences
Select address*
Enter self-identification**
Individualaddress*
Groupaddress*
Areaaddress*
Enter natureof distress
Includenature of dis-
tress?
Yes
No
Routine
Safety DistressUrgencyEnter self-
identification**
Acknowl-edge reply?
Distresscoordinatesavailable?
Yes
No
No
Additionalinformation?
Allacceptable?
Enter distresscoordinates
and time ***
Enter telecommandinformation
Processorcopies message
No
No
No
Yes
Tele-command infor-
mation?
YesSpecify
telecommandinformation?
Specify receiverfrequency
information
Receiverfrequency infor-
mation?
Transmitterfrequency infor-
mation?
Yes
No
Specifytransmitterfrequency
information
No
No
No
Enter ship’sposition***
Entertelephonenumber
Ship’sposition infor-
mation?
Semi-automatic/
automatic ship-to-shore required?
Acknowl-edge RQ or BQ?
RQBQ
End of sequence
Processor addsacknowledge
BQ
Processoradds end ofsequence
End ofmessage
Yes
Yes
Yes
Yes
Yes
For reply message, processor copiesself-identification of received message.
The self-identification of a callingsequence is automatically entered.
This may be entered automatically.
*
**
***
Processor addsacknowledge
RQ
IndividualIndividual* Area Group*
Distress ACK/relay, urgency, safety
All ships
Select address*
Note – This chart is informative only.
376 Maritime Manual
0493-06
–15°
–20°
15° 20°
a
–15° –10° –5°
–5°
–10°
E
N
S
c
–20°
10°
5°
0° 5° 10°
b
ϕc
λc
∆ϕ
∆λ
2 1 1 0 1 2 0 3 0 5
12 0 0 1 0 1 0 1
1 1 0 0 2 0 2 0 3 0
0
a)
b)
c)
ϕaλa ∆ϕ ∆λ
∆ϕ = 3° ∆λ = 5°
∆ϕ = 10° ∆λ = 10°
∆ϕ = 20° ∆λ = 30°
FIGURE 6
Geographic coordinates
W
Formatspecifier
Category
Category
Category
Sector
ϕa = – 11° (South) λa = 12° (East)
ϕb = – 10° (South) λb = 10° (East)
ϕc = 10° (North) λc = – 20° (West)
Formatspecifier
Formatspecifier
Part C – Rec. ITU-R M.493-13 377
Legend for Tables 4.1 to 4.10.2
Symbol/expression Meaning
! Required
"# Required for backward compatibility
Symbols 100-127 Symbols in accordance with Table 3
Area Coded in accordance with Annex 1, § 5.3
Frequency Coded in accordance with Annex 1, § 8.2.2
MMSI Coded in accordance with Annex 1, § 5.2
Pos1 Coded in accordance with Annex 1, § 8.1.2
Pos2 Coded in accordance with Annex 1, § 8.3.2.3.1
Pos3 Coded in accordance with Annex 1, § 8.3.2.3.2
Pos4 Coded in accordance with Annex 1, § 8.3.2.3.3
Pos5 Coded in accordance with Recommendation ITU-R M.821
UTC Coded in accordance with Annex 1, § 8.1.3
n/a This field is not included in this call
ECC Coded in accordance with Annex 1, § 10.2
expan1 Expansion sequence 1
expan2 Expansion sequence 2
expan3 Expansion sequence 3
Does not apply
NOTE 1 – For Class A and B all functions are identical for VHF and MF. HF does not apply to
Class B.
378
M
aritim
e Ma
nu
al
TABLE 4.1
Distress alerts
Fre-
quency
band Type
Applicable to Technical format of call sequence
Ship
station
Class A/B
Ship
station
Class D
Ship
station
Class E Coast station
Format
specifier
(2 identical)
Self-ID
(5)
Message
EOS
(1)
ECC
(1)
EOS
(2 identical)
Rec. ITU-R
M.821
expansion
sequence
(9)
1 2 3 4
Nature
of
distress
(1)
Distress
coordi-
nates
(5)
Time
(2)
Subse-
quent
commu-
nications
(1) Tx Rx Tx Rx Tx Rx Tx Rx
VHF Distress
(RT) !# !# !# !# # # # !# 112 MMSI 100 to 111 Pos1 UTC 100 127 ECC 127 expan1
Distress
(EPIRB) # !# # !# # # # !# 112 MMSI 112 Pos1 UTC 126 127 ECC 127 expan1
MF/HF Distress
(RT) !# !# # # !# !# # !# 112 MMSI 100 to 111 Pos1 UTC 109 127 ECC 127 expan1
Distress
(FEC) !# !# # # # !# # !# 112 MMSI 100 to 111 Pos1 UTC 113 127 ECC 127 expan1
Rec. ITU-R M.821 expansion sequence
Type Expansion data specifier
(1)
Enhanced position resolution
(4)
EOS
(1)
ECC
(1)
EOS
(2 identical)
expan1 100 Pos5 127 ECC 127
Pa
rt C –
Rec. IT
U-R
M.4
93
-13
3
79
TABLE 4.2
Distress acknowledgements
Type
Applicable to Technical format of call sequence
Ship
station
Class A/B
Ship
station
Class D
Ship
station
Class E
Coast
station
Format
specifier
(2 iden-
tical)
Cate-
gory
(1)
Self-
ID
(5)(1)
Tele-
command
(1)
Message
EOS
(1)
ECC
(1)
EOS
(2 iden-
tical)
Rec. ITU-R
M.821
expansion
sequence
(9)
0 1 2 3 4
Distress
MMSI
(5)
Nature of
distress
(1)
Distress
coordi-
nates
(5)
Time
(2)
Subse-
quent
commu-
nications
(1)
Fre-
quency
band Tx Rx Tx Rx Tx Rx Tx Rx
VHF Distress acknowl-
edgement (RT) ! !# $ ! $ $ ! ! 116 112 MMSI 110 MMSI 100 to 111 Pos1 UTC 100 127 ECC 127 expan1
Distress acknowl--edgement (EPIRB)
! !# $ ! $ $ ! ! 116 112 MMSI 110 MMSI 112 Pos1 UTC 126 127 ECC 127 expan1
MF Distress acknowl-edgement (RT)
! !# $ $ $ ! ! ! 116 112 MMSI 110 MMSI 100 to 111 Pos1 UTC 109 127 ECC 127 expan1
Distress acknowl-
edgement (FEC) ! !# $ $ $ ! ! ! 116 112 MMSI 110 MMSI 100 to 111 Pos1 UTC 113 127 ECC 127 expan1
HF Distress acknowl-
edgement (RT) $ !# $ $ $ ! ! ! 116 112 MMSI 110 MMSI 100 to 111 Pos1 UTC 109 127 ECC 127 expan1
Distress acknowl-
edgement (FEC) $ !# $ $ $ ! ! ! 116 112 MMSI 110 MMSI 100 to 111 Pos1 UTC 113 127 ECC 127 expan1
(1) Distress acknowledgments where the transmitting MMSI and ship in distress MMSI are the same, the
message should be interpreted as a self Cancel operation. This should be displayed on all receiving
stations. The function should be implemented on new equipment. (NOTE 1 – Class D and E
equipment should be capable of transmitting a self cancel.)
The message should match the received distress
alert information, except for manually
generated distress acknowledgements by coast
stations.
Rec. ITU-R M.821 expansion sequence
Type Expansion data specifier
(1)
Enhanced position resolution
(4)
EOS
(1)
ECC
(1)
EOS
(2 identical)
expan1 100 Pos5 127 ECC 127
380
M
aritim
e Ma
nu
al
TABLE 4.3
Distress relays
Type
Applicable to Technical format of call sequence
Ship
station
Class
A/B
Ship
station
Class
D
Ship
station
Class
E
Coast
station
Format
specifier
(2 iden-
tical)
Address
(5)
Cate-
gory
(1)
Self-
ID
(5)
Tele-
command
(1)
Message
EOS
(1)
ECC
(1)
EOS
(2 iden-
tical)
Rec. ITU-R
M.821
expansion
sequence
(9)
0 1 2 3 4
Distress
MMSI
(5)
Nature of
distress
(1)
Distress
coordi-
nates
(5)
Time
(2)
Subse-
quent
com-
munica
tions
(1)
Frequency
band Tx Rx Tx Rx Tx Rx Tx Rx
VHF Individual (RT) ! ! !(1)
$ $ ! ! 120 MMSI 112 MMSI 112 MMSI 100 to 111 Pos1 UTC 100 117 ECC 117 expan2
Individual
(EPIRB) ! ! $ !
(1)$ $ ! ! 120 MMSI 112 MMSI 112 MMSI 112 Pos1 UTC 126 117 ECC 117 expan2
Geographic
area (RT) $ " $ "
(1)$ $ $ " 102 Zone 112 MMSI 112 MMSI 100 à 111 Pos1 UTC 100 127 ECC 127 expan1
Geographic
area (EPIRB) $ " $ "
(1)$ $ $ " 102 Zone 112 MMSI 112 MMSI 112 Pos1 UTC 126 127 ECC 127 expan1
All ships (RT) ! ! $ !(1)
$ $ ! ! 116 n/a 112 MMSI 112 MMSI 100 to 111 Pos1 UTC 100 127 ECC 127 expan1
All ships
(EPIRB) ! ! $ !
(1)$ $ ! ! 116 n/a 112 MMSI 112 MMSI 112 Pos1 UTC 126 127 ECC 127 expan1
MF/HF Individual (RT) ! ! $ $ ! ! ! 120 MMSI 112 MMSI 112 MMSI 100 to 111 Pos1 UTC 109 117 ECC 117 expan2
Individual
(FEC) ! ! $ $ $ ! ! ! 120 MMSI 112 MMSI 112 MMSI 100 to 111 Pos1 UTC 113 117 ECC 117 expan2
Geographic
area (RT) ! ! $ $ $ ! ! ! 102 Zone 112 MMSI 112 MMSI 100 to 111 Pos1 UTC 109 127 ECC 127 expan1
Geographic
area (FEC) ! ! $ $ $ ! ! ! 102 Zone 112 MMSI 112 MMSI 100 to 111 Pos1 UTC 113 127 ECC 127 expan1
(1) This call is not applicable to hand-held equipment.
Pa
rt C –
Rec. IT
U-R
M.4
93
-13
3
81
TABLE 4.3 (end)
Type
Applicable to Technical format of call sequence
Ship
station
Class
A/B
Ship
station
Class
D
Ship
station
Class
E
Coast
station
Format
specifier
(2 iden-
tical)
Ad-
dress
(5)
Cate-
gory
(1)
Self-ID
(5)
Tele-
command
(1)
Message
EOS
(1)
ECC
(1)
EOS
(2 iden-
tical)
Rec. ITU-R
M.821
expansion
sequence
(9)
0 1 2 3 4
Distress
MMSI
(5)
Nature of
distress
(1)
Distress
coordi-
nates
(5)
Time
(2)
Subse-
quent
commu
nica-
tions
(1)
Frequency
band Tx Rx Tx Rx Tx Rx Tx Rx
MF/HF
(End )
All ships
(RT) $ " $ $ $ " $ " 116 n/a 112 MMSI 112 MMSI 100 to 111 Pos1 UTC 109 127 ECC 127 expan1
All ships
(FEC) $ " $ $ $ " $ " 116 n/a 112 MMSI 112 MMSI 100 to 111 Pos1 UTC 113 127 ECC 127 expan1
$ $ $ $ $ $ $ $
The message should match the received
distress alert information, except for manually
generated relays observed or notified by non-
DSC means.
Rec. ITU-R M.821 expansion sequence
Type Expansion data specifier
(1)
Enhanced position resolution
(4)
EOS
(1)
ECC
(1)
EOS
(2 identical)
expan1 100 Pos5 127 ECC 127
expan2 100 Pos5 117 ECC 117
382
M
aritim
e Ma
nu
al
TABLE 4.4
Distress relay acknowledgements
Frequency
band Type
Applicable to Technical format of call sequence
Ship
station
Class
A/B
Ship
station
Class
D
Ship
station
Class
E
Coast
station Format
specifier
(2 iden-
tical)
Ad-
dress
(5)
Cate-
gory
(1)
Self-
ID
(5)
Tele-
command
(1)
Message
EOS
(1)
ECC
(1)
EOS
(2 iden-
tical)
Rec. ITU-R
M.821
expansion
sequence
(9)
0 1 2 3 4
Distress
MMSI
(5)
Nature of
distress
(1)
Distress
coordi-
nates
(5)
Time
(2)
Subse-
quent
commu-
nications
(1) Tx Rx Tx Rx Tx Rx Tx Rx
VHF
Individual
(RT) ! ! ! !(1)
$ $ ! ! 120 MMSI 112 MMSI 112 MMSI 100 to 111 Pos1 UTC 100 122 ECC 122 expan3
Individual
(EPIRB) ! ! $ !(1)
$ $ ! ! 120 MMSI 112 MMSI 112 MMSI 112 Pos1 UTC 126 122 ECC 122 expan3
All ships
(RT) $ ! $ !(1)
$ $ ! ! 116 n/a 112 MMSI 112 MMSI 100 to 111 Pos1 UTC 100 122 ECC 122 expan3
All ships
(EPIRB) $ ! $ !(1)
$ $ ! ! 116 n/a 112 MMSI 112 MMSI 112 Pos1 UTC 126 122 ECC 122 expan3
MF/HF
Individual
(RT) ! ! $ $ ! ! ! ! 120 MMSI 112 MMSI 112 MMSI 100 to 111 Pos1 UTC 109 122 ECC 122 expan3
Individual
(FEC) ! ! $ $ $ ! ! ! 120 MMSI 112 MMSI 112 MMSI 100 to 111 Pos1 UTC 113 122 ECC 122 expan3
All ships
(RT) $ " $ $ $ ! ! ! 116 n/a 112 MMSI 112 MMSI 100 to 111 Pos1 UTC 109 122 ECC 122 expan3
All ships
(FEC) $ " $ $ $ ! ! ! 116 n/a 112 MMSI 112 MMSI 100 to 111 Pos1 UTC 113 122 ECC 122 expan3
(1) This call is not applicable to hand-held equipment.
The message should match the received distress
relay call information.
Rec. ITU-R M.821 expansion sequence
Type Expansion data specifier
(1)
Enhanced position resolution
(4)
EOS
(1)
ECC
(1)
EOS
(2 identical)
expan3 100 Pos5 122 ECC 122
Pa
rt C –
Rec. IT
U-R
M.4
93
-13
3
83
TABLE 4.5
Urgency and safety calls – All ships
Frequency
band Type
Applicable to Technical format of call sequence
Ship
station
Class A/B
Ship
station
Class D
Ship
station
Class E
Coast
station Format
specifier
(2 identical)
Category
(1)
Self-ID
(5)
Message
EOS
(1)
ECC
(1)
EOS
(2 identical)
1 2
1st tele-
command
(1)
2nd tele-
command
(1)
Frequency
(6) Tx Rx Tx Rx Tx Rx Tx Rx
VHF All modes RT !# !# !(2)
!# $# $# !# !# 116 108 or 110 MMSI 100 126 Frequency 127 ECC 127
Duplex RT(1) $# "# $# "# $# $# $# "# 116 108 or 110 MMSI 101 126 Frequency 127 ECC 127
Medical transports !# !# $# $# $# $# $# !# 116 110 MMSI 100 111 Frequency 127 ECC 127
Ships and aircraft
(Res. 18) !# !# $# $# $# $# $# !# 116 110 MMSI 100 110 Frequency 127 ECC 127
MF/HF J3E RT $# $# $# $# $# $# $# "# 116 108 or 110 MMSI 109 126 Frequency 127 ECC 127
F1B FEC $# $# $# $# $# $# $# "# 116 108 or 110 MMSI 113 126 Frequency 127 ECC 127
(1) See § 8.3.1.3.
(2) This call is not applicable to hand-held equipment.
384
M
aritim
e Ma
nu
al
TABLE 4.6
Urgency and safety – Geographic area calls
Frequency
band Type
Applicable to Technical format of call sequence
Ship
station
Class A/B
Ship
station
Class D
Ship
station
Class E
Coast
station Format
specifier
(2 identical)
Address
(5)
Category
(1)
Self-ID
(5)
Message
EOS
(1)
ECC
(1)
EOS
(2 iden-
tical)
1 2
1st tele-
command
(1)
2nd tele-
command
(1)
Fre-
quency
(6) Tx Rx Tx Rx Tx Rx Tx Rx
MF/HF
J3E (RT) ! ! $# $# ! ! ! ! 102 Area 108 or 110 MMSI 109 126
Fre-
quency 127 ECC 127
F1B (FEC) ! ! $# $# $# $# ! ! 102 Area 108 or 110 MMSI 113 126
Fre-
quency 127 ECC 127
Medical transports ! ! $# $# $# $# $# ! 102 Area 110 MMSI 109 or 113 111
Fre-
quency 127 ECC 127
Ships and aircraft
(Res. 18) ! ! $# $# $# $# $# ! 102 Area 110 MMSI 109 or 113 110
Fre-
quency 127 ECC 127
Pa
rt C –
Rec. IT
U-R
M.4
93
-13
3
85
TABLE 4.7
Urgency and safety – Individual calls and their acknowledgements
Type
Applicable to Technical format of call sequence
Ship
station
Class
A/B
Ship
station
Class
D
Ship
station
Class
E
Coast
stationFormat
specifier
(2 identical)
Address
(5)
Category
(1)
Self-ID
(5)
Message
EOS
(1)
ECC
(1)
EOS
(2 identical)
1 2 3
1st tele-
command
(1)
2nd tele-
command
(1)
Frequency
or pos
number
(6)
Time
(2)
Frequency
band Tx Rx Tx Rx Tx Rx Tx Rx
VHF All modes RT ! ! $ ! $ $ ! ! 120 MMSI 108 or 110 MMSI 100 126 Frequency n/a 117 ECC 117
Duplex RT(1) $# " # $ $ $ $ " 120 MMSI 108 or 110 MMSI 101 126 Frequency n/a 117 ECC 117
RT
acknowledgement! ! ! $ $ $ ! ! 120 MMSI 108 or 110 MMSI 100 126 Frequency n/a 122 ECC 122
Unable to comply
acknowledgement! ! ! $ $ $ ! ! 120 MMSI 108 or 110 MMSI 104 100 to 109 Frequency n/a 122 ECC 122
Position request ! ! $ $ $ $ ! $ 120 MMSI 108 MMSI 121 126 Pos3 n/a 117 ECC 117
Position
acknowledgement! ! $ $ $ $ $ ! 120 MMSI 108 MMSI 121 126 Pos4 UTC 122 ECC 122
Test ! ! ! ! $ $ ! ! 120 MMSI 108 MMSI 118 126 126 n/a 117 ECC 117
Test
acknowledgement! ! ! ! $ $ ! ! 120 MMSI 108 MMSI 118 126 126 n/a 122 ECC 122
386
M
aritim
e Ma
nu
al
TABLE 4.7 (end)
Type
Applicable to Technical format of call sequence
Ship
station
Class
A/B
Ship
station
Class
D
Ship
station
Class
E
Coast
station
Format
specifier
(2 identical)
Address
(5)
Category
(1)
Self-ID
(5)
Message
EOS
(1)
ECC
(1)
1 2 3
1st tele-
command
(1)
2nd tele-
command
(1)
Frequency
or pos
number
(6)
Time
(2)
Frequency
band Tx Rx Tx Rx Tx Rx Tx Rx
EOS
(2 iden-
tical)
MF/HF J3E RT ! ! $ $ $ ! ! ! 120 MMSI 108 or 110 MMSI 109 126 Frequency n/a 117 ECC 117
J3E RT with pos
number ! $ $ $ $ $ $ ! 120 MMSI 108 or 110 MMSI 109 126 Pos2 n/a 117 ECC 117
J3E RT
acknowledgement! ! $ $ ! $ ! ! 120 MMSI 108 or 110 MMSI 109 126 Frequency n/a 122 ECC 122
F1B FEC or ARQ ! ! $ $ $ $ ! ! 120 MMSI 108 or 110 MMSI 113 or 115 126 Frequency n/a 117 ECC 117
F1B FEC or ARQ
with pos number ! $ $ $ $ $ $ ! 120 MMSI 108 or 110 MMSI 113 or 115 126 Pos2 n/a 117 ECC 117
F1B FEC or ARQ
acknowledgement! ! $ $ $ $ ! ! 120 MMSI 108 or 110 MMSI 113 or 115 126 Frequency n/a 122 ECC 122
Unable to comply
acknowledgement! ! $ $ ! $ ! ! 120 MMSI 108 or 110 MMSI 104 100 to 109 Frequency n/a 122 ECC 122
Position request ! ! $ $ $ $ ! $ 120 MMSI 108 MMSI 121 126 Pos3 n/a 117 ECC 117
Position
acknowledgement! ! $ $ $ $ $ ! 120 MMSI 108 MMSI 121 126 Pos4 UTC 122 ECC 122
Test ! ! $ $ ! ! ! ! 120 MMSI 108 MMSI 118 126 126 n/a 117 ECC 117
Test
acknowledgement! ! $ $ ! ! ! ! 120 MMSI 108 MMSI 118 126 126 n/a 122 ECC 122
(1) See § 8.3.1.3.
Pa
rt C –
Rec. IT
U-R
M.4
93
-13
3
87
TABLE 4.8
Routine group calls
Frequency
band Type
Applicable to Technical format of call sequence
Ship
station
Class
A/B
Ship
station
Class
D
Ship
station
Class
E
Coast
stationFormat
specifier
(2 identical)
Address
(5)
Category
(1)
Self-ID
(5)
Message
EOS
(1)
ECC
(1)
EOS
(2 identical)
1 2
1st tele-
command
(1)
2nd tele-
command
(1)
Frequenc
y
(6) Tx Rx Tx Rx Tx Rx Tx Rx
VHF All mode RT ! ! ! ! $ $ ! ! 114 MMSI 100 MMSI 100 126 Frequency 127 ECC 127
Duplex RT(1) " $ $ $ $ " 114 MMSI 100 MMSI 101 126 Frequency 127 ECC 127
MF/HF J3E RT ! ! ! ! ! ! 114 MMSI 100 MMSI 109 126 Frequency 127 ECC 127
F1B FEC ! ! $ $ $ $ ! ! 114 MMSI 100 MMSI 113 126 Frequency 127 ECC 127
(1) See § 8.3.1.3.
388
M
aritim
e Ma
nu
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TABLE 4.9
Routine individual calls and their acknowledgements
Frequen
cy
band Type
Applicable to Technical format of call sequence
Ship
station
Class
A/B
Ship
station
Class
D
Ship
station
Class
E
Coast
station Format
specifier
(2 identical)
Address
(5)
Category
(1)
Self-ID
(5)
Message
EOS
(1)
ECC
(1)
EOS
(2 identical)
1 2
1st tele-
command
(1)
2nd tele-
command
(1)
Frequency
or pos
number
(6) Tx Rx Tx Rx Tx Rx Tx Rx
VHF All mode RT ! ! ! ! $ $ ! ! 120 MMSI 100 MMSI 100 126 Frequency 117 ECC 117
Duplex RT(1) " $ $ " 120 MMSI 100 MMSI 101 126 Frequency 117 ECC 117
RT acknowledgement ! ! ! ! $ $ ! ! 120 MMSI 100 MMSI 100 126 Frequency 122 ECC 122
Data ! ! $ $ $ $ ! ! 120 MMSI 100 MMSI 106 126 Frequency 117 ECC 117
Data acknowledgement ! ! $ $ $ $ ! ! 120 MMSI 100 MMSI 106 126 Frequency 122 ECC 122
Unable to comply
acknowledgement ! ! $ $ ! ! 120 MMSI 100 MMSI 104 100 to 109 Frequency 122 ECC 122
Polling $ ! $ $ $ $ ! " 120 MMSI 100 MMSI 103 126 126 117 ECC 117
Polling acknowledgement ! $ $ $ $ $ " ! 120 MMSI 100 MMSI 103 126 126 122 ECC 122
Pa
rt C –
Rec. IT
U-R
M.4
93
-13
3
89
TABLE 4.9 (end)
Type
Applicable to Technical format of call sequence
Ship
station
Class
A/B
Ship
station
Class
D
Ship
station
Class
E
Coast
stationFormat
specifier
(2 iden-
tical)
Address
(5)
Cate-
gory
(1)
Self-ID
(5)
Message
EOS
(1)
ECC
(1)
EOS
(2 identical)
1 2
1st tele-
command
(1)
2nd tele-
command
(1)
Frequency
or pos
number
(6)
Frequency
band Tx Rx Tx Rx Tx Rx Tx Rx
MF/HF J3E RT ! ! $ $ ! ! ! ! 120 MMSI 100 MMSI 109 126 Frequency 117 ECC 117
J3E RT with pos number ! $ $ $ ! $ $ ! 120 MMSI 100 MMSI 109 126 Pos2 117 ECC 117
J3E RT acknowledgement ! ! $ $ ! ! ! ! 120 MMSI 100 MMSI 109 126 Frequency 122 ECC 122
F1B FEC, ARQ or data ! ! $ $ $ $ ! ! 120 MMSI 100 MMSI 113, 115, 106 126 Frequency 117 ECC 117
FEC, ARQ or data with
pos number ! $ $ $ $ $ $ ! 120 MMSI 100 MMSI 113, 115, 106 126 Pos2 117 ECC 117
F1B FEC, ARQ or data
acknowledgement ! ! $ $ $ $ ! ! 120 MMSI 100 MMSI 113, 115, 106 126 Frequency 122 ECC 122
Unable to comply
acknowledgement ! ! $ $ ! ! 120 MMSI 100 MMSI 104 100 à 109 Frequency 122 ECC 122
Polling $ ! $ $ $ $ ! " 120 MMSI 100 MMSI 103 126 126 117 ECC 117
Polling acknowledgement ! $ $ $ $ $ " ! 120 MMSI 100 MMSI 103 126 126 122 ECC 122
(1) See § 8.3.1.3.
390
M
aritim
e Ma
nu
al
TABLE 4.10.1
Semi/auto VHF (optional)
Type
Applicable to Technical format of call sequence
Ship
station
Class
A/B
Ship
station
Class D
Ship
station
Class E
Coast
station Format
specifier
(2 iden-
tical)
Address
(5)
Category
(1)
Self-ID
(5)
Message
EOS
(1)
ECC
(1)
EOS
(2 iden-
tical)
1 2 3
1st tele-
command
(1)
2nd tele-
command
(1)
Frequency
(3)
Number
(2-9) Tx Rx Tx Rx Tx Rx Tx Rx
Request ! ! !(2)
!(2)
$ $# ! ! 123 MMSI 100 MMSI 100, 101, 106 126 Frequency Number 117 ECC 117
Able to comply
acknowledgement ! ! !
(2)!
(2)$ $# ! ! 123 MMSI 100 MMSI 100, 101, 106 126 Frequency Number 122 ECC 122
Start of call
(on working channel) ! $ !
(2)$ $ $# $ ! 123 MMSI 100 MMSI 100, 101, 106 126 Frequency Number 127 ECC 127
Unable to comply
acknowledgement ! ! !
(2)!
(2)$ $# ! ! 123 MMSI 100 MMSI 104 100-109 Frequency Number 122 ECC 122
End of call request
(on working channel) ! $ !
(2)$ $ $# $ ! 123 MMSI 100 MMSI 105 126 Frequency Number 117 ECC 117
End of call
acknowledgement
(on working channel)(1) $ ! $ !
(2)$ $# ! $# 123 MMSI 100 MMSI 105 126 Duration Number 122 ECC 122
(1) Upon call completion the coast station may send the end of call acknowledgement without a request from the ship station. The EOS symbol being 127.
(2) This call is not applicable to hand-held equipment.
NOTE 1 – See Recommendation ITU-R M.689.
NOTE 2 – For Class D symbol 123 does not need to be displayed.
Pa
rt C –
Rec. IT
U-R
M.4
93
-13
3
91
TABLE 4.10.2
Semi/auto MF/HF (optional)
Type
Applicable to Technical format of call sequence
Ship
station
Class
A/B
Ship
station
Class D
Ship
station
Class E
Coast
station
Format
specifier
(2 iden-
tical)
Address
(5)
Category
(1)
Self-ID
(5)
Message
EOS
(1)
ECC
(1)
EOS
(2 iden-
tical)
1 2 3
1st tele
command
(1)
2nd tele-
command
(1)
Frequency
or pos
number
(6)
Number
(2-9) Tx Rx Tx Rx Tx Rx Tx Rx
J3E RT/F1B FEC/ARQ $ $ $ $ $ $ $ $
Request coast station $ ! $ $ $ ! ! $ 123 MMSI 100 MMSI 109, 113, 115 126 Frequency Number 117 ECC 117
Request ship station ! $ $ $ ! $ $ ! 123 MMSI 100 MMSI 109, 113, 115 126 126 or Pos2 Number 117 ECC 117
Able to comply
acknowledgement ! ! $ $ ! ! ! ! 123 MMSI 100 MMSI 109, 113, 115 126 Frequency Number 122 ECC 122
Signal strength test by ship
(on working channel)(1) ! $ $ $ ! $ $ ! 123 MMSI 100 MMSI 109, 113, 115 126 Frequency Number 117 ECC 117
Coast station acknowledgement
with new working frequency(1) $ ! $ $ $ ! ! $ 123 MMSI 100 MMSI 109, 113, 115 126
New
frequency Number 122 ECC 122
Call start: Coast station
acknowledgement with same
working frequency(1) $ ! $ $ $ ! ! $ 123 MMSI 100 MMSI 109, 113, 115 126
Same
frequency Number 122 ECC 122
Unable to comply ! ! $ $ ! ! ! ! 123 MMSI 100 MMSI 104 100 a 109 Frequency Number 122 ECC 122
End of call request (on working
channel) ! $ $ $ ! $ $ ! 123 MMSI 100 MMSI 105 126 Frequency Number 117 ECC 117
End of call acknowledgement (on
working channel)(2) $ ! $ $ $ ! ! $ 123 MMSI 100 MMSI 105 126 Duration Number 122 ECC 122
(1) This call involves signal strength testing. The ship requests call by sending the coast station its position. Once the ship or coast station is able to comply the ship station sends test DSCs on the
working frequency. If the coast station acknowledges with a new working frequency, the ship station sends a test DSC on the new frequency. When the coast station acknowledges with an
unchanged frequency, the subsequent communication may begin.
(2) Upon call completion the coast station may send the end of call acknowledgement without a request from the ship station. The EOS symbol being 127.
NOTE 1 – See Recommendation ITU-R M.1082.
NOTE 2 – For Class E symbol 123 does not need to be displayed.
392 Maritime Manual
TABLE 5
Frequency or channel information
TABLE 6
Position information (Annex 1, § 8.3.2.3)
Frequency
0
1
2
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
The frequency in multiples of 100 Hz as indicated by
the figures for the digits HM, TM, M, H, T, U. This
should be used for MF, HF equipment.
3 X X X X X The HF/MF working channel number indicated by
the values of the digits TM, M, H, T and U. This
should be used for backward compatibility in receive
only mode.
Channels 8 X X X X X Only used for Recommendation ITU-R M.586
equipment.
9 0 X(1) X X X The VHF working channel number indicated by the
values of the digits M, H, T and U.
HM TM M H T U
Character
3
Character
2
Character
1(2)
(1) If the M digit is 1 this indicates that the ship stations transmitting frequency is being used as a simplex channel
frequency for both ship and coast stations. If the M digit is 2 this indicates that the coast stations transmitting
frequency is being used as a simplex channel frequency for both ship and coast stations. If the M digit is 0, this
indicates the frequency being used is in accordance with RR Appendix 18 for both single and two frequency
channels.
(2) Character 1 is the last character transmitted.
Quadrant
digit
NE = 0
NO = 1
SE = 2
SO = 3
Latitude Longitude
Tens
of
degrees
Units
of
degrees
Tens
of
minutes
Units
of
minutes
Hundreds
of
degrees
Tens
of
degrees
Units
of
degrees
Tens
of
minutes
Units
of
minutes
55 X X X X X X X X X X
Character
6
Character
5
Character
4
Character
3
Character
2
Character
5(1)
(1) Character 1 is the last character transmitted.
Part C – Rec. ITU-R M.493-13 393
Annex 2
Equipment classes
1 Equipment classes only apply to shipborne equipment
Class A equipment, which includes all the facilities defined in Annex 1, will comply
with the IMO GMDSS carriage requirements for MF/HF installations and/or VHF
installations.
Class B equipment providing minimum facilities for equipment on ships not required to
use Class A equipment and complying with the minimum IMO GMDSS carriage
requirements for MF and/or VHF installations.
Class D equipment is intended to provide minimum facilities for VHF DSC distress,
urgency and safety as well as routing calling and reception, not necessarily in full
accordance with IMO GMDSS carriage requirements for VHF installations.
Class E equipment is intended to provide minimum facilities for MF and/or HF DSC
distress, urgency and safety as well as routine calling and reception, not necessarily in
full accordance with IMO GMDSS carriage requirements for MF/HF installations.
Class A and Class B equipment may support the optional semi-automatic/automatic
service in accordance with Recommendations ITU-R M.689, ITU-R M.1082 and
Tables 4.10.1 and 4.10.2 and are encouraged to do so.
Class D and Class E equipment may also support the optional semi-automatic/automatic
service.
NOTE 1 – Class C, F and G equipment as defined in earlier versions of this Recommendation
(e.g., Recommendations ITU-R M.493-5 (Geneva, 1992) and ITU-R M.493-7 (Geneva, 1995))
did not provide vital minimum DSC functions (transmitting and receiving distress alerts) and
have therefore been withdrawn.
394 Maritime Manual
2 Class requirements for B, D and E are given in § 3, 4 and 5 (See
Tables 4.1 to 4.10.2 for technical requirements)
3 Class B (MF and/or VHF only)
3.1 Transmit capabilities
3.1.1 Format specifier: Distress
All ships
Geographic area
Individual station
Semi-automatic/automatic service
Ships having common interest (group).
3.1.2 The numerical identification of the called station (address).
3.1.3 Category: Distress
Urgency
Safety
Routine.
3.1.4 Self-identification (automatically inserted).
3.1.5 Messages
3.1.5.1 For distress alerts:
Message 1: Nature of distress, defaulting to undesignated distress
Message 2: Distress coordinates
Message 3: Time for last position update
Message 4: Type of subsequent communication:
MF: J3E
VHF: F3E/G3E simplex.
3.1.5.2 For distress relay calls:
First telecommand: Distress relay
Identification of the ship: As defined in Annex 1
Messages 1 to 4: As § 3.1.5.1.
Part C – Rec. ITU-R M.493-13 395
3.1.5.3 For distress acknowledgement calls:
First telecommand: Distress acknowledgement
Identification of the ship: As defined in Annex 1
Messages 1 to 4: As § 3.1.5.1.
3.1.5.4 For all other calls:
First telecommand: Unable to comply.
MF: For individual station calls, J3E or “test” (see
Annex 1 § 8.4); for calls using the
semi-automatic/automatic MF-services, J3E
or “end of call”.
VHF: For individual station calls, F3E/G3E or
“polling” (see Annex 1 § 8.4); for calls using
the semi-automatic/automatic VHF-services
F3E/G3E or “end of call”.
Second telecommand: No information.
Frequency/channel or ship’s position: As defined in Annex 1.
Selection information (semi-
automatic/automatic service): Telephone number of public telephone
subscriber.
3.1.6 End of sequence character: As defined in Annex 1.
3.2 Receive capabilities
3.2.1 Receive and be capable of displaying all the information in calls listed in § 3.1
plus all distress relay calls having the format specifier “geographical area calls”, all
distress acknowledgement calls and all “unable to comply” calls.
3.2.2 Audible alarm upon reception of any DSC call.
396 Maritime Manual
4 Class D (VHF only)1
4.1 Transmit capabilities
4.1.1 Format specifier: Distress
All ships
Individual station
Ships having common interest (group).
4.1.2 The numerical identification of the called station (address).
4.1.3 Category: Distress
Urgency
Safety
Routine.
4.1.4 Self-identification (automatically inserted).
4.1.5 Messages
4.1.5.1 For distress calls:
Message 1: Nature of distress, defaulting to undesignated distress
Message 2: Distress coordinates
Message 3: Time for last position update
Message 4: Type of subsequent communication: F3E/G3E simplex.
4.1.5.2 For all other calls:
First telecommand: F3E/G3E simplex
Unable to comply
Polling.
Second telecommand: No information.
Frequency/channel information: VHF working channel, defaulting to
channel 16 for urgency and safety calls and a
recognized intership channel
(RR Appendix 18) for all other calls.
4.1.6 End of sequence character: As defined in Annex 1.
_______________
1 Requirements for sub-category hand-held equipment are specified in Annex 1 Tables 4.1
to 4.10.2.
Part C – Rec. ITU-R M.493-13 397
4.2 Receive capabilities
Receive and be capable of displaying all the information in calls listed in § 4.1 plus all
distress relay calls except those having the format specifier “geographical area calls”,
all distress acknowledgement calls and all “unable to comply” calls.
5 Class E (MF and/or HF only)
5.1 Transmit capabilities
5.1.1 Format specifier: Distress
Geographic area
Individual station
Ships having common interest (group).
5.1.2 The numerical identification of the called station (address).
5.1.3 Category: Distress
Urgency
Safety
Routine.
5.1.4 Self-identification (automatically inserted).
5.1.5 Messages
5.1.5.1 For distress calls:
Message 1: Nature of distress, defaulting to undesignated distress
Message 2: Distress coordinates
Message 3: Time for last position update
Message 4: Type of subsequent communication J3E.
5.1.5.2 For all other calls:
First telecommand: J3E telephony
Unable to comply
Test.
Second telecommand: No information.
Frequency/channel information: MF/HF working channel, on MF defaulting to
2 182 kHz for urgency and safety calls.
398 Maritime Manual
5.1.6 End of sequence character: As defined in Annex 1.
5.2 Receive capabilities
Receive and be capable of displaying all the information in calls listed in § 5.1 plus all
distress relay calls having the format specifier “geographical area calls”, all distress
acknowledgement calls and all “unable to comply” calls.
Part C – Rec. ITU-R M.585-5 399
RECOMMENDATION ITU-R M.585-5
Assignment and use of maritime mobile service identities
(1982-1986-1990-2003-2007-2009)
The ITU Radiocommunication Assembly,
considering
a) the need for a unique ship identity for safety and telecommunication purposes;
b) that the unique number should be the maritime mobile service identity
(MMSI);
c) the need for this identity to be usable with automated radiocommunication
systems;
d) that the identities assigned to ship stations, coast stations, aircraft participating
in search and rescue operations, aids to navigation, craft associated with a parent ship,
and used for establishing group calls should be of a similar nature;
e) that it is possible to use the MMSI to establish a telephone call to a ship after
routing through the public switched networks to an appropriate coast station;
f) that the public switched networks in many countries have restrictions on the
maximum number of digits that may be dialled or keyed to identify the called ship
station and the routing coast station, which would prevent the translation of the
complete MMSI directly into a diallable number for the ship that is compliant with
ITU-T Recommendation E.164;
g) that whatever restrictions may be required should, in the interests of the
development of automatic shore-to-ship operations, be as few as possible;
h) that mobile-satellite systems enable the maritime community to participate in
or interwork with international public correspondence telecommunication systems on a
fully automatic basis, utilizing the numbering, naming and addressing scheme
pertaining to the service being used;
j) that the current generation of mobile-satellite systems participating in the
global maritime distress and safety system (GMDSS) have signalling and routing
characteristics requiring ships using these networks to have an MMSI ending with three
zeroes;
400 Maritime Manual
k) that the numbering scheme specified for future generations of mobile-satellite
systems participating in the GMDSS will be designed to meet the needs of the
international public correspondence service and is unlikely to offer the facility to
incorporate any part of the MMSI in a diallable number for a ship,
recommends
1 that ships complying with the International Convention for the Safety of Life
at Sea, 1974, as amended, and other ships equipped with automated
radiocommunication systems, including Automatic Identification Systems (AIS),
Digital Selective Calling (DSC), and/or carrying alerting devices of the GMDSS should
be assigned maritime mobile service identities in accordance with Annexes 1, 2, 3, 4 or
5 to this Recommendation, as appropriate;
2 that ship, coast stations, and aircraft participating in search and rescue
operations using digital selective calling equipment in accordance with
Recommendation ITU-R M.493 should use their 9-digit numerical identities transmitted
as a 10-digit address/self-identity, normally with a digit 0 added at the end of the
identity (see also Recommendation ITU-R M.1080);
3 that ship, coast stations, and non-shipborne stations using AIS equipment in
accordance with Recommendation ITU-R M.1371 should use their 9-digit numerical
identities;
4 for the purpose of ensuring compatibility with the GMDSS, the numbers,
names and addresses of ship earth stations participating in international
telecommunication services should be made readily available to all authorized entities
by the telecommunication service providers concerned;
5 that the guidance given in Annex 6 to this Recommendation should be
employed regarding the reuse of MMSI, particularly those with three trailing zeroes.
Annex 1
Assignment of identification to ship station
1 Ships participating in the maritime radio services mentioned in recommends 1
should be assigned a nine digit unique ship station identity in the format
M1I2D3X4X5X6X7X8X9 where in the first three digits represent the Maritime
Identification Digits (MID) and X is any figure from 0 to 9. The MID denotes the
geographical area of the administration responsible for the ship station so identified.
Part C – Rec. ITU-R M.585-5 401
2 Restrictions may apply with respect to the maximum number of digits, which
can be transmitted on some national telex and/or telephone networks for the purpose of
ship station identification.
3 The maximum number of digits that could be transmitted over the national
networks of many countries for the purpose of determining ship station identity was six.
The digits carried on the network to represent the ship station identity are referred to as
the “ship station number” in this text and in the relevant ITU-R Recommendations. The
use of the techniques described below should have made it possible for the coast
stations of such countries to engage in the automatic connection of calls to ship stations.
To obtain the required nine digit ship station identity a series of trailing zeros would
have to be added automatically to the ship station number by the coast station in order
to complete a shore-originated telephone call, for example, carried over the public
switched telephone network:
Ship station number Ship station identity
M1I2D3X4X5X6 M1I2D3X4X5X6070809
4 In accordance with the above, and the relevant ITU-T Recommendations, a
numbering plan was instituted for Inmarsat Standard B, C and M systems, which also
requires that MMSI with three trailing zeroes be assigned to ships fitting standard B, C
and M ship earth stations.
5 The above restrictions do not necessarily apply to Inmarsat Standard C
systems, as they are not diallable terminals from the public switched telephone network
but are only data terminals.
6 With respect to Inmarsat Standard B and M systems and as long as the above
restrictions apply, ships reasonably expected to be affected by the above limitations
should only be assigned ship station identities with X7X8X9 = 000.
7 Group ship station call identities for calling simultaneously more than one ship
are formed as follows:
01M2I3D4X5X6X7X8X9
where the first figure is zero and X is any figure from 0 to 9. The MID represents only
the territory or geographical area of the administration assigning the group ship station
call identity and does not therefore prevent group calls to fleets containing more than
one ship nationality.
402 Maritime Manual
8 With the evolution of global mobile-satellite systems, ships earth stations are
able to participate in international public correspondence telecommunication services.
Ship earth stations having this functionality may be assigned international
telecommunication numbers that have no direct correspondence with the ship station
MMSI. Those authorized to assign the numbers, names and addresses associated with
such ship earth stations should maintain a record of the cross reference relationships
with the MMSI, for example in an appropriate database. For the purposes of GMDSS
the details of these relationships should be made available to authorized entities such as
but not limited to the Rescue Coordination Centres (RCC)1. Such availability should be
on an automatic basis, 24 hours per day 365 days per year.
Annex 2
Assignment of identification to coast station
1 Coast stations and other stations on land participating in the maritime radio
services mentioned in recommends 2 should be assigned a nine-digit unique coast
station identity in the format 0102M3I4D5X6X7X8X9 where the digits 3, 4 and 5 represent
the MID and X is any figure from 0 to 9. The MID reflects the territory or geographical
area in which the coast station or coast earth station is located.
2 As the number of coast stations decreases in many countries, an administration
may wish to assign MMSI of the format above to harbour radio stations, pilot stations,
system identities and other stations participating in the maritime radio services. The
stations concerned should be located on land or on an island in order to use the
00MIDXXXX format.
3 The administration may use the sixth digit to further differentiate between
certain specific uses of this class of MMSI, as shown in the example applications
below:
a) 00MID1XXX Coast radio stations
b) 00MID2XXX Harbour radio stations
c) 00MID3XXX Pilot stations, etc.
4 This format scheme creates blocks of 999 numbers for each category of
station, however the method is optional and should be used only as a guidance. Many
other possibilities exist if the administration concerned wishes to augment the scheme.
_______________
1 IMO Resolution A.1001(25) requires that distress priority communications in these systems
should, as far as possible, be routed automatically to an RCC.
Part C – Rec. ITU-R M.585-5 403
5 Group coast station call identities for calling simultaneously more than one
coast station are formed as a subset of coast station identities, as follows:
0102M3I4D5X6X7X8X9
where the first two figures are zeros and X is any figure from 0 to 9. The MID
represents only the territory or geographical area of the administration assigning the
group coast station call identity. The identity may be assigned to stations of one
administration which are located in only one geographical region as indicated in the
relevant ITU-T Recommendations.
6 The combination 0102M3I4D506070809 should be reserved for a Group Coast
Station Identity and should address all 00MIDXXXX stations within the administration.
The administration may further augment this use with additional Group Call identities,
i.e. 00MID1111, etc.
7 For the purpose of the GMDSS the details of these MMSI assignments should
be made available to authorized entities such as, but not limited to, RCC. Such
availability should be on an automatic basis, 24 hours per day 365 days per year.
8 The combination 010293949506070809 is reserved for the All Coast Stations
Identity and should address all VHF 00XXXXXXX stations. It is not applicable to MF
or HF coast stations.
Annex 3
Assignment of identification to aircraft
1 When an aircraft is required to use maritime mobile service identities for the
purposes of conducting search and rescue communications with stations in the maritime
mobile service, the responsible administration should assign a nine-digit unique aircraft
identity, in the format 111213M4I5D6X7X8X9 where the digits 4, 5 and 6 represent the
MID and X is any figure from 0 to 9. The MID represents only the territory or
geographical area of the administration assigning the aircraft call identity.
2 The format shown above will accommodate 999 aircraft per MID. If the
administration concerned has more Search and Rescue (SAR) aircraft than 999 they
may use an additional country code (MID) if it is already assigned by the ITU.
3 The administration may use the seventh digit to differentiate between certain
specific uses of this class of MMSI, as shown in the example applications below:
a) 111MID1XX Fixed-wing aircraft
b) 111MID5XX Helicopters
404 Maritime Manual
4 This format scheme creates blocks of 99 numbers for each of the category of
stations, however, the method shown here is optional.
5 The combination 111213M4I5D6070809 should be reserved for a Group Aircraft
Identity and should address all 111MIDXXX stations within the administration. The
administration may further augment this with additional Group Call identities,
i.e. 111MID111, etc.
6 For the purpose of search and rescue the details of these MMSI assignments
should be made available to authorized entities such as, but not limited to, RCC. Such
availability should be on an automatic basis, 24 hours per day 365 days per year.
7 The MMSI assigned to SAR aircraft should also be available from the ITU
MARS database (see Radio Regulations (RR) No. 20.16).
Annex 4
Assignment of identification to AIS Aids to Navigation (AtoN)
1 When a means of automatic identification is required for a station aiding
navigation at sea, the responsible administration should assign a nine-digit unique
number in the format 9192M3I4D5X6X7X8X9 where the digits 3, 4 and 5 represent the
MID and X is any figure from 0 to 9. The MID represents only the territory or
geographical area of the administration assigning the call identity for the navigational
aid.
2 The format shown above applies to all types of AtoN as listed in the most
recent version of Recommendation ITU-R M.1371, see AIS Message 21 parameter
“Type of aids to navigation” and the associated table for this parameter. This format is
used for all AIS stations for the transmission of messages that relate to AtoN. In the
case where an AIS base station is collocated with an AIS AtoN station the messages
related to the base station operation should be assigned an identification number in the
format given in Annex 2.
3 The format scheme shown above will accommodate 10 000 AtoN per MID. If
the administration concerned has more than 10 000 they may use an additional country
code (MID) if it is already assigned by the ITU giving a further 10 000 identities.
4 The administration may use the sixth digit to differentiate between certain
specific uses of the MMSI, as shown in the example applications below:
a) 99MID1XXX Physical AIS AtoN
b) 99MID6XXX Virtual AIS AtoN
Part C – Rec. ITU-R M.585-5 405
5 This format scheme creates blocks of 999 numbers for each category of
station, however the method shown here is optional and should be used only as a
guidance.
6 In addition to the use of the sixth digit to differentiate between specific
navigational aids as explained above, the seventh digit may be used for national
purposes, to define areas where the AIS AtoN are located or types of AIS AtoN to the
discretion of the administration concerned.
7 The details of these MMSI assignments should be made available but not
limited to the International Association of Marine Aids to Navigation and Lighthouse
Authorities (IALA) and appropriate national authorities.
8 The assigned MMSI to aids of navigation should also be available from the
ITU MARS database (see RR No. 20.16).
Annex 5
Assignment of identification to craft associated with a parent ship
1 Craft associated with a parent ship, need unique identification. These crafts
which participate in the maritime mobile service should be assigned a nine-digit unique
number in the format 9182M3I4D5X6X7X8X9 where the digits 3, 4 and 5 represent the
MID and X is any figure from 0 to 9. The MID represents only the territory or
geographical area of the administration assigning the call identity for the craft
associated with a parent ship.
2 This numbering format is only valid for devices on board craft associated with
a parent ship. A craft may carry multiple devices which would be identified by the
MMSI assigned to the craft. These devices may be located in lifeboats, life-rafts, MOB-
boats or other craft belonging to a parent ship.
3 A unique MMSI should be assigned for each craft associated with a parent
ship and will have to be separately registered and linked to the MMSI of the parent
ship.
4 The format scheme shown above will accommodate 10 000 crafts associated
with parent ships per MID. If the administration concerned has more than 10 000 they
may use an additional country code (MID) if it is already assigned by the ITU giving a
further 10 000 identities.
5 The assigned MMSI to these craft associated with a parent ship should also be
available from the ITU MARS database (see RR No. 20.16).
406 Maritime Manual
Annex 6
Guidance on the conservation and management of MMSI
1 Administrations should employ the following measures to manage the limited
MMSI numbering resource, particularly for the reuse of MMSI with three trailing
zeroes, in order to avoid depletion of MID and the corresponding MMSI series:
a) implement effective national procedures for MMSI assignment and
registration;
b) provide the Bureau with regular updates of assigned numbers in conformity
with RR No. 20.16;
c) ensure that the period from the expiration of the ship station licence associated
with the number assignment until the date of reassignment of that number is
sufficient for the changes to be incorporated in the relevant ITU service
publications, taking into account the standard intervals between successive
published editions;
d) ensure that when ships move from the flag of registration of one
administration to that of another administration, all of the assigned means of
ship station identification, including the MMSI, are reassigned as appropriate
and that the changes are notified to the Bureau as soon as possible
(see RR No. 20.16).
2 It is essential for a lapsed number assignment to remain dormant before taking
it back into use again, in order to avoid confusion over the origin of distress
communications or over the responsible parties for billing and reconciling accounts for
maritime radiocommunications.
3 The objective is to ensure that a period of five years should pass before a
lapsed MMSI is reused and entered into national and international databases pursuant to
RR No. 20.16.
4 Administrations could also apply the above procedures to MMSI assigned
with 2, 1 or no trailing zeroes in the interests of the long term conservation of MMSI
and MID resources. However these number formats are normally not critical to the
assignment of an additional MID to an administration (see Section VI of RR
Article 19).
Part C – Rec. ITU-R M.628-4 407
RECOMMENDATION ITU-R M.628-4
Technical characteristics for search
and rescue radar transponders
(1986-1990-1992-1994-2006)
Scope
This Recommendation contains technical characteristics for search and rescue radar
transponders (SART). A SART is used for locating a ship or survival craft at sea when
it is in distress.
A ship or survival craft at sea can use a SART to indicate that it is in distress. The
SART can be detected by radars operating in the 9 GHz frequency band.
The ITU Radiocommunication Assembly,
considering
a) that Regulations III/6.2.2 and IV/7.1.3 of the 1988 Amendments to the
International Convention for the Safety of Life at Sea (SOLAS), 1974 require the
carriage of radar transponders operating in the 9 GHz frequency band for locating the
ship when it is in distress at sea or its survival craft;
b) that such radar transponders may also be used by ships not subject to the 1974
SOLAS Convention; some of these radar transponders may be installed with a float-free
release and activation arrangement or with a float-free Emergency Position Indicating
Radio Beacon (EPIRB) or float-free satellite EPIRB;
c) that Regulations V/19 of the 2000 Amendments to the 1974 SOLAS
Convention require that passenger ships irrespective of size and cargo ships of
300 gross tonnage and upwards carry a radar installation or if they are of 5 000 gross
tonnage and upwards, two radar installations; from 1 February 1995, the radar
installation or at least one of the radar installations shall be capable of operating in the
9 GHz frequency band;
d) that the International Maritime Organization (IMO) has adopted a
Recommendation on performance standards for survival craft radar transponders for use
in search and rescue operations (Resolution A.802(19));
408 Maritime Manual
e) that location is part of the basic requirements for the GMDSS;
f) that a locating system would be more effective if the radar transponder was in
conformity with internationally agreed technical and operating characteristics,
recommends
1 that the technical characteristics of search and rescue radar transponders
(SART) operating in the frequency range 9 200-9 500 MHz should be in accordance
with Annex 1;
2 that the maximum detection range of a SART having technical characteristics
in accordance with Annex 1 by a radar conforming with IMO Resolution MSC.192(79)
should be assessed using its measured technical characteristics in conjunction with the
theoretical method given in Annex 2;
3 Notes 1 and 2 are part of this Recommendation.
NOTE 1 – The propagation losses of a SART signal caused by a survival craft and its occupants
are explained in Annex 3.
NOTE 2 – The technical characteristics of circular polarization SARTs are described in
Annex 4.
Annex 1
Technical characteristics for search and rescue radar transponders
operating over the band 9 200-9 500 MHz
1 Frequency: 9 200-9 500 MHz.
2 Polarization: horizontal or circular.
3 Sweep rate: 5 µs per 200 MHz, nominal.
4 The response signal should consist of 12 sweeps.
5 Form of sweep: sawtooth, forward sweep time: 7.5 µs ± 1 µs,
return sweep time: 0.4 µs ± 0.1 µs.
The response should commence with a return
sweep.
6 Pulse emission: 100 µs nominal.
7 e.i.r.p.: not less than 400 mW (equivalent to +26 dBm).
8 Effective receiver sensitivity: better than –50 dBm (equivalent to 0.1 mW/m2)
(see Note 1).
Part C – Rec. ITU-R M.628-4 409
9 Duration of operation: 96 h in stand-by condition followed by 8 h of
transponder transmissions while being
continuously interrogated with a pulse
repetition frequency of 1 kHz.
10 Temperature range: ambient: –20° C to +55° C,
stowage: –30° C to +65° C.
11 Recovery time following excitation: 10 µs or less.
12 Effective antenna height: ≥1 m (see Note 2).
13 Delay between receipt of radar signal and start of transmission: 0.5 µs or less.
14 Antenna vertical beamwidth: at least ± 12.5° relative to the radar
transponders’ horizontal plane.
15 Antenna azimuthal beamwidth: omnidirectional within ± 2 dB.
NOTE 1 – Effective receiver sensitivity includes antenna gain.
– Effective receiver sensitivity of better than –50 dBm applies to interrogating radar pulses
(medium and long) of > 400 ns.
– Effective receiver sensitivity of better than –37 dBm applies to interrogating radar pulses
(short) of ≤ 100 ns.
– The receiver should be capable of correct operation when subjected to the radiated field
(28 dB(W/m2)) emitted from a shipborne radar complying with IMO
Resolution MSC.192(79) at any distance > 20 m.
NOTE 2 – This effective antenna height is applicable for equipment required by
Regulations III/6.2.2 and IV/7.1.3 of the 1988 Amendments to the 1974 SOLAS Convention.
Annex 2
The maximum detection range of a SART of given or measured e.i.r.p. and effective
receiver sensitivity when deployed with a radar conforming with IMO Resolution
MSC.192(79) may be assessed using Fig. 1.
The essential parameters of the radar are:
– transmitter power 25 kW,
– antenna gain 30 dBi,
– antenna height 15 m,
– receiver sensitivity –94 dBm.
410 Maritime Manual
Figure 1 shows the propagation curves for SARTs of height 0.5 m, 1 m and 1.5 m in a
fairly calm sea (wave height 0.3 m). For rougher seas, the sea reflection coefficient is
reduced and the propagation curves move back towards the free space line depending
on atmospheric refraction. For an SART of 1 m height, the maximum detection range is
at least 5 NM.
The method of using Fig. 1 is as follows:
– calculate the radar received power (Pr) at range 1 NM using the formula:
Pr = SART e.i.r.p. × radar antenna gain × (λ/4 π R)2
that is Pr (dBm) = SART e.i.r.p. (dBm) –87 dB;
– set the calculated Pr against point A on the radar received power scale and
complete the scale (10 dB per division);
– set the SART effective receiver sensitivity (ERS) on the transponder received
power scale and read the intercept with the appropriate propagation curve at
that level to obtain the radar to SART maximum detection range;
– take the –94 dBm level on the radar received power scale and read the
intercept with the appropriate propagation curve at that level to obtain the
SART to radar maximum detection range.
The smaller of the two maximum detection ranges so obtained is the required
assessment of SART maximum detection range, which should be at least 5 NM as
required by IMO Resolution A.802(19).
Part C – Rec. ITU-R M.628-4 411
12
55
A
062
8-0
1
FIG
UR
E 1
Pro
pa
ga
tion
cu
rv
es f
or
measu
rem
ent
of
SA
RT
max
imu
m d
etec
tion
ra
ng
e
Sea
bo
rne
sear
ch (
15
m)
Hr
=
Fre
e sp
ace
Transponder received power, (dBm) (SART ERS)Ptr
Ran
ge (N
M)
Radar received power, (dBm)Prr
412 Maritime Manual
Annex 3
Effects of antenna height and obstruction of the signal path by a survival
craft and its occupants on the detection range of SARTs
1 Introduction
This Annex discusses the effects on the propagation path of SART signals, taking into
account the height of the SART antenna above the surface of the sea and also the
attenuation caused by the materials of the survival craft and its occupants.
2 Effects of SART antenna height on detection range
This Recommendation requires that the height of the installed SART antenna should be
at least 1 m above the sea surface in order to obtain the five nautical mile detection
range required by IMO Resolution A.802(19). Practical tests have confirmed this
performance. Tests on a sample of six SARTs from different manufacturers gave
detection ranges between 8.2 NM and 9.2 NM with an antenna height of 1 m.
2.1 Tests have also shown the importance of maintaining a SART antenna height
of at least 1 m. The following results were obtained with a SART in a survival craft:
– SART lying flat on the floor: range 1.8 NM
– SART standing upright on the floor: range 2.5 NM
– SART floating in the water: range 2.0 NM
3 Effects of survival craft on SART signal
Tests have been made with a SART mounted on a survival craft to give a 1 m antenna
height, in order to determine whether the body of the survival craft and its occupants
may cause an obstruction.
3.1 Figures 2-4 give the results of these tests carried out on two different models
of an eight-man SOLAS life-raft. In each case, the SART was placed at the centre of a
turntable in an open field site, and was triggered with a pulsed radar signal. Each set of
measurements was conducted with and without the life-raft and "survivors" present,
keeping the SART at the centre of the turntable.
3.2 Figure 2 shows the results obtained from a SART mounted on a telescopic
pole fitted to the life-raft’s antenna mounting. In this case, the SART antenna was level
with the canopy support tube of the raft. One of the rafts had little effect on the SART
signal, whereas the other (which has carbon in the material of the support tube) caused
a dip in the signal through an angle of about 30°.
Part C – Rec. ITU-R M.628-4 413
3.3 Figure 3 shows the results obtained with the same rafts, but with a SART
designed to hang from the support tube, inside the canopy of the raft. A smaller loss of
signal was noted due to the carbon loaded tubes, as the signal was only passing through
the vertical sections. Dips were also noted, however, due to the presence of retro-
reflective tape on the outside of the life-raft canopies. On one raft, there was a severe
reduction in signal over a very small angle, due to the proximity of a Lithium battery
pack mounted on the canopy for powering the life-raft location light.
3.4 Figure 4 shows the blanking effect caused by a survivor holding the SART at
arm’s length. In this case however the SART height was only 0.5 m.
414 Maritime Manual
4
2
0
0 45 90 135 180 225 270 315 360
7
8
0628-02
7.5
7.2
6.5
6.1
FIGURE 2
Pole mounted SART
Rel
ativ
e p
ow
er (
dB
)
Azimuth angle
Signal masked by carbon loadedcanopy support tube
Mounted on raft 1
Mounted on raft 2
Ap
pro
xim
ate detec tio
n ran
ge (N
M)
Part C – Rec. ITU-R M.628-4 415
2
0
180900
8
7
66
0628-03
7.2
6.5
6.1
FIGURE 3
SART hung inside raft
Rel
ativ
e p
ow
er (
dB
)
Azimuth angleSignal masked by battery for light
Mounted in raft 1
Mounted in raft 2
Ap
pro
xim
at e de tect io
n r an
ge (N
M)
7.5
Dips caused by reflective tapeand/or carbon in support tube
416 Maritime Manual
2
0 7
6
5
7
6
5
7
6
5
0628-04
6.5
6.1
FIGURE 4
Hand-held SART
Rel
ativ
e p
ow
er (
dB
)
Azimuth angle
App
rox
ima te d
etec tion ran
ge (N
M)
Hand held in raft 1
5.2
Part C – Rec. ITU-R M.628-4 417
3.5 On each figure approximate detection ranges are given. These are derived
theoretically assuming an 8 NM detection range for a 1 m height SART and a 7 NM
range for 0.5 m height.
3.6 It can be seen from the figures that best performance was obtained with the
pole mounted SART where the reduction in detection range due to the survival craft
was generally no more than 0.5 NM. In all cases there was reduced performance over
narrow sectors of 1.5-2.0 NM but in practice with the survival craft moving in the sea
this will not be a serious operational problem. The reduction shown in Fig. 4 caused by
a person, will not be significant in practice as a person seated in a survival craft is lower
in height than 1 m.
3.7 The above results were obtained with the survival craft dry as it was on a test
site. Table 1 gives the propagation loss for the canopy and air tube cloths used in a
number of different manufacturers’ survival crafts. The last two entries give the loss
when the materials are sprayed with sea water. It can be seen that in the worst case the
additional loss for wet material was 3.35 dB which equates to a reduction in detected
range of about a further 0.5 NM.
TABLE 1
Transmission loss through canopy of life-raft (measurement results)
Transmission loss (dB) vs. slant of
canopy
Test Sample Thickness
(mm)
Weight
(kg/m2) Slant
θ = 0° θ = 30° θ = 45° θ = 60°
1 Canopy cloth of
company A
0.18 0.22 0 –0.1 –0.2 0
2 Air tube cloth of
company A
0.53 0.7 –0.05 –0.05 –0.3 –0.2
3 Canopy cloth of
company B
0.25 0.27 0 –0.1 –0.15 –0.05
4 Air tube cloth of
company B
0.57 0.67 0 –0.4 –0.4 –0.45
5 Canopy cloth of
company C
0.26 0.3 –0.2 –0.5 –0.3 –0.4
6 Air tube cloth of
company C
0.54 0.67 –0.6 –1.4 –1.9 –2.4
418 Maritime Manual
TABLE 1 (end)
4 Conclusions
The tests indicated that properly mounted SARTs will achieve the detection range
required by IMO, even allowing for the blanketing effects of the survival craft. There is
no necessity to mount the SART more than 1 m above the sea particularly if the extra
height is likely to lead to difficulties by survivors in achieving the mounting, but in
future improved antenna mountings may be feasible giving additional detection range.
4.1 The tests did not consider the effect on SART performance of a radar reflector
but it would be expected that this would seriously degrade the SART response.
Survivors are advised not to deploy a SART and a radar reflector on the same survival
craft because the reflector may obscure the SART.
Annex 4
Performance of circular polarization SARTs
Foreword
Horizontal polarization has been used as the method of polarization for SARTs. Recent
examinations in Japan have shown that circular polarization would be suitable for use
with SARTs. A SART using circular polarization with a helical antenna was made for
trial purposes, and water tank experiments and sea trials were conducted. The results
showed the superiority of circular polarization used with SARTs and it was concluded
that this will enable a reduction in the size of SARTs.
Test Sample Thickness
(mm)
Weight
(kg/m2)
Transmission loss (dB) vs. slant of
canopy
Slant
θ = 0° θ = 30° θ = 45° θ = 60°
7 Spraying salt
water
(4.8% NaCl)
over “1”
– – –0.35 –0.55 –0.95 –1.1
8 Spraying salt
water
(4.8% NaCl)
over “3”
– – –1.3 –1.9 –2.6 –3.4
Measurement freqency: 9.4 GHz
Sample size: 600 × 800 mm
Part C – Rec. ITU-R M.628-4 419
1 Characteristics of SART signal in the tank tests
Measurements of the received power of the SART signal and observations of visibility
of the signal on radar PPI were carried out in an artificial waves water tank at a research
laboratory in Japan. The results showed that circular polarization was superior to
horizontal polarization for SARTs.
2 Characteristics of SART signal in the on-sea trial
This experiment was conducted in 2000, in cooperation with ships and aircraft of the
maritime authorities of Japan in Sagami Bay, by observing the visibility of the SART
signal on the radars on board the ships and aircraft. In the meantime, the received power
of the SART signal was measured by a land-based radar. The following results were
obtained:
a) With aircraft radar, the maximum visible distance of the SART signal of
circular polarization was 37 NM, while that of horizontal polarization was
30 NM. This confirms the superiority of circular polarization.
b) With marine radar, the maximum visible distance of the SART signal of
circular polarization was 14 NM, while that of horizontal polarization was
11.5 NM. These results confirm the superiority of circular polarization.
c) With land-based marine radar, the result shown in Fig. 5 was obtained. The
SART of circular polarization was moved on the sea by an escorting small
vessel. The distance between the radar and the SART was changed. The
received power of the SART was measured by the land-based marine radar. In
Fig. 5, the black dots show the actually measured SART signal of circular
polarization, and dotted lines show the theoretical value of SART signal of
horizontal polarization. The measured data always appears above the
theoretical value curve for “SART to radar”. The appearance of the SART
signal of circular polarization on the radar PPI was stronger and clearer than
that of horizontal polarization. These results confirm the superiority of circular
polarization. The reason is as follows: Because the electric field revolves,
circular polarization is resolved in the horizontal polarization element and the
vertical polarization element. For these two composition elements, the
reflection characteristic of the surface of the sea is different. Therefore the
curve of reception strength when the direct wave and the surface of the sea
reflection wave interfere changes with distance. This phenomenon leads to the
detectable distance of a circular polarization wave SART increasing over
horizontal polarization SART by 30% or more.
420 Maritime Manual
FIGURE 5
Observed data of SART signal of circular polarization and theoretical value
of horizontal polarization
Furthermore, in 2004, measurements of the received power of a SART signal were
carried out in rough weather conditions using a marine radar of a research laboratory in
Japan. As a result, it was confirmed that a SART with circular polarization was not
inferior compared with that of horizontal polarization.
Part C – Rec. ITU-R M.689-2 421
RECOMMENDATION ITU-R M.689-2
INTERNATIONAL MARITIME VHF RADIOTELEPHONE SYSTEM WITH
AUTOMATIC FACILITIES BASED ON DSC SIGNALLING FORMAT**
(Question ITU-R 93/8)
(1990-1992-1994) Rec. ITU-R M.689-2
The ITU Radiocommunication Assembly,
recommends
1. that the operational procedures described in Annex 1 be observed when operating an
international radiotelephone system with automatic facilities based on the DSC signalling
format, and using the public correspondence channels listed in RR Appendix 18;
2. that the same RR Appendix 18 channel can be used for both automatic and manual
operation by the same coast station depending on the requirements of the ship stations;
3. that the technical characteristics of the ship and coast station equipment should be in
accordance with Annex 2.
ANNEX 1
Operational procedures
1. Introduction
These procedures are initiated by using DSC on the VHF calling channel and based on
the technical characteristics and operational procedures detailed in Recommendations
ITU-R M.493 and ITU-R M.541. Connection to the PSTN is effected using any appropriate
VHF public correspondence working channel listed in RR Appendix 18 without in any way
impairing their use for manual operation.
Appendix 1 illustrates the timing of the call set-up, calling and acknowledgement
sequences described by these procedures in the ship-to-shore direction and in the shore-to-ship
direction.
_______________
** Coast stations may also use other procedures with automatic facilities based on DSC signalling format
directly on VHF radiotelephone working channels.
422 Maritime Manual
2. Operational procedures in the ship-to-shore direction
2.1 Ship station initiates call
2.1.1 The user aboard the ship (hereafter referred to as the user) composes the calling
sequence (see Note 1) on his DSC equipment as follows:
– selects the format specifier 123 (automatic/semi-automatic service);
– enters address (identification) of required VHF coast station;
– selects the category routine (100);
– (the ship station self-identification is entered automatically);
– selects first telecommand 101 (duplex F3E/G3E) or 100 (simplex F3E/G3E) or 106 (data)
(see Note 2) and second telecommand as appropriate;
– inserts subscriber number required (e.g. telephone number);
– selects “end of sequence” signal “RQ”.
Note 1 – It is assumed that commercial equipment will be produced which simplifies the
composition of the calling sequence. In practice the user should only need to key the VHF coast
station address and the required subscriber number, all other information being inserted
automatically.
Note 2 – Duplex mode of operation should be used for data communications.
2.1.2 The user selects the VHF DSC calling channel (channel 70 of RR Appendix 18) and
initiates transmission of the sequence on the calling channel. In order to reduce the probability of
call collisions, the DSC equipment should automatically inhibit transmission of this sequence
until the calling channel is clear of any signal.
2.1.3 If the ship station does not receive an error-free acknowledgement from the called
coast station (see § 2.2) within 5 s, the calling sequence should be automatically repeated. If an
error-free acknowledgement is still not received within a further 5 s, then any further repetitions
should be effected by manually initiating a new calling sequence. Such further repetitions to the
same coast station should not, however, be initiated until at least 15 min have elapsed.
2.2 Coast station acknowledgement
2.2.1 The coast station should, within 3 s of receipt of the calling sequence, initiate the
transmission of an acknowledgement sequence on the DSC calling channel. The coast station
equipment should also automatically inhibit transmission of the acknowledgement until the
calling channel is clear.
2.2.2 If the coast station can comply immediately with the call request, then it should
immediately:
– radiate an “engaged channel” signal on the coast station transmit frequency of the
appropriate working channel;
Part C – Rec. ITU-R M.689-2 423
– transmit the acknowledgement sequence which should contain the same information as in
the call request with the following exceptions:
– the address will be that of the ship;
– the self-identification will be that of the coast station;
– the working channel number will be included;
– the “end of sequence” signal will be “BQ”.
2.2.3 If the coast station cannot comply immediately with the call request due to the
appropriate working channel(s) being busy, then the acknowledgement sequence should be as in
§ 2.2.2 except that the first telecommand will be 104 (unable to comply) and the second
telecommand will be 103 (queue) if the optional ring-back procedure is applied, else 102 (busy)
and three symbols No. 126 should be included in the channel information field.
2.2.4 If the coast station cannot comply for other reasons, the acknowledgement sequence
should be as in § 2.2.3, except that the second telecommand signal should be one of symbol
numbers 100-109 as appropriate.
2.2.5 The ship station, on receipt of an error-free acknowledgement in accordance with
§ 2.2.2 (ability to comply), should, within 5 s of receipt, change to the working channel
indicated in the acknowledgement and transmit, on that working channel, a carrier for a
minimum period of 2 s. Fully automated ship station equipment should, within that transmission,
transmit a DSC call which is identical to the initial call (see § 2.1.1) except that the “end of
sequence” signal should be 127 (see Note 1).
Note 1 – In some regional applications, ships do not transmit DSC signals on the working
channels. Equipment on ships sailing beyond these regional applications and participating in the
automated service, should be able to comply with the requirements for the fully automated
service.
2.2.6 If the ship station receives an error-free acknowledgement in accordance with § 2.2.3
indicating “unable to comply – queue” then, if the user still requires the call connection, the ship
station should continue to monitor the DSC calling channel for any calls from the coast station.
2.2.7 The ship station, on receipt of an acknowledgement indicating “unable to comply” in
accordance with § 2.2.4 (or, if the coast station does not operate the “ring-back” procedure
(§ 2.3.2), in accordance with § 2.2.3), should, if an automatic connection is still required, initiate
an appropriate new call in accordance with § 2.1.
2.2.8 If the coast station transmitted an acknowledgement indicating “unable to comply” in
accordance with § 2.2.4 (or, if the coast station does not operate the “ring-back” procedure
(§ 2.3.2), in accordance with § 2.2.3), then it should take no further action with respect to the
call request.
424 Maritime Manual
2.3 Procedures subsequent to the exchange of initial DSC calls
2.3.1 Mandatory procedure
2.3.1.1 If the coast station transmitted an acknowledgement indicating “able to comply”
(§ 2.2.2) then, if a DSC call (§ 2.2.5) containing the same self-identification as that of the calling
ship is detected on the coast station receive frequency of the working channel, the coast station
should immediately start to dial the required subscriber number (see Note 1, § 2.3.1.2).
2.3.1.2 If a further call identical to the original calling sequence is received from the ship
station within 16 s of receipt of the original calling sequence (see § 2.1.1) then the coast station
should repeat the acknowledgement (§ 2.2.2). If a DSC call in accordance with § 2.3.1.1
(Note 1) is not detected within this 16 s period then the coast station should remove the
“engaged channel” signal.
Note 1 – Some coast stations detect only the presence of a carrier at this stage. In areas of high-
traffic density, carrier detection may not ensure that the calling ship has transferred to the
working channel and should be avoided where practicable.
2.3.2 Optional “ring-back” procedure
The following additional sequence will tend to reduce repetitive ship calling and
provide a better service to the ship:
2.3.2.1 If the coast station transmitted an “unable to comply – queue” acknowledgement (see
§ 2.2.3) then the ship’s identification and required subscriber number should be stored until an
appropriate working channel becomes available. This information should be retained for a
period of 15 min.
2.3.2.2 If an appropriate working channel becomes available within the 15 min period, the
coast station should immediately radiate an “engaged channel” signal on the coast station
transmit frequency of that working channel and initiate a DSC call on the DSC calling channel
to the ship station with the same format as the acknowledgement (see § 2.2.2) except that the
“end of sequence” should be “RQ”. If no appropriate working channel becomes available within
this 15 min period then the information should be cleared and no further action taken by the
coast station.
2.3.2.3 If an acknowledgement of the above call is not received from the ship station (see
§ 2.3.2.4) within 5 s then the coast station should repeat the call. If there is no acknowledgement
to this second call then the ship’s call details should be cleared and the “engaged channel” signal
removed.
2.3.2.4 The ship station, on receipt of such a calling sequence (§ 2.3.2.2) should, if the call
connection is still required, automatically initiate an acknowledgement within 2 s on the calling
channel (the acknowledgement being transmitted only when the channel is clear). This
acknowledgement should be identical to the received calling sequence except that the address
should be that of the coast station, the self-identification should be that of the ship station and
the “end of sequence” should be “BQ”.
Part C – Rec. ITU-R M.689-2 425
2.3.2.5 The ship station should then continue to listen to the calling channel for a further 5 s,
then change to the working channel and transmit a carrier and DSC call as described in § 2.2.5.
If a further calling sequence is received within this 5 s period, the acknowledgement should be
repeated.
2.3.2.6 The coast station, after receipt of an acknowledgement from the ship station, should,
when a DSC call in accordance with § 2.3.1.1 (see Note 1, § 2.3.1.2) is detected on this working
channel, immediately start to dial the subscriber number.
2.3.2.7 If, after a period of 15 min a ship has not received a call as indicated in § 2.3.2.2 then,
if the call connection is still required, a new call should be manually initiated in accordance with
§ 2.1.1.
2.4 Call connection
2.4.1 Once the coast station begins dialling the subscriber number it should connect the line
circuit to the radio path. Timing of the call for billing purposes should commence after the
subscriber answers, i.e. “off-hook” condition detected. The call connection is now retained and
the user should commence communication as soon as the subscriber answers.
For a ship working on a duplex basis (see Note 1) the carrier must be transmitted for
the total duration of the call.
For a ship not working on a duplex basis the carrier must be activated at least once
every 45 s. Such activation, when it does not occur naturally (due to the ship transmitting)
should preferably be automatic. If automatic activation is not provided then means could be
provided to timely alert the user that carrier activation is necessary.
Note 1 – Ships capable of working duplex but using a semi-duplex operation should use the
telecommand signal 100.
2.4.2 If the called subscriber does not answer within a period of 1 min from completion of
dialling, then the call should be considered as not started and the coast station should clear the
circuit in accordance with § 2.5.5. The user, on hearing the ringing tones stop or hearing
anything other than “ringing” tones (e.g. engaged, number unobtainable, etc.) should refrain
from any further transmissions on the working channel. If a further call is required, the user
should initiate a new call on the DSC calling channel. The ship’s equipment should prevent the
transmission of a new call on the DSC calling channel until at least 5 s have elapsed after
clearance to prevent malfunction of the coast station “call completion due to ship station
clearance” procedure (see § 2.4.4.1, 2.4.4.2 and 2.5.5).
2.4.3 If a further call is attempted from the same ship within the “time-out period” (semi-
duplex operation, see § 2.4.4.2), the coast station may use the information derived from the call
to disconnect the previously allocated working channel.
2.4.4 If, during any period of the call, the coast station equipment detects the absence of the
ship’s carrier, the following procedures apply:
2.4.4.1 If the first telecommand indicated duplex operation and the coast station equipment
detects the absence of the ship’s carrier for a period greater than 5 s, then the call should be
considered to be complete.
426 Maritime Manual
2.4.4.2 If the first telecommand indicated simplex operation and the coast station equipment
detects the absence of the ship’s carrier for a period greater than 45 s, then the call should be
considered to be complete.
2.4.5 If during any period of the call, a fully automated ship station equipment detects the
absence of the coast station’s carrier for a period greater than 5 s, the call should be considered
to be complete.
2.5 Call completion (Note 1, § 2.2.5 applies to § 2.5.1 to 2.5.4)
2.5.1 When the ship station wishes to terminate the call connection to the PSTN, it transmits
an “end of call” DSC call on the working channel and removes the carrier. The format of this
call should be the same as that described in § 2.1.1 except that the first telecommand should be
105 (end of call) and the second telecommand should be 126.
2.5.2 On receipt of that call (see Note 1), if it contains the same self-identification as that of
the calling ship, the landline is disconnected, the call timing is stopped, the coast station
transmits a DSC acknowledgement on the working channel within 1 s of receipt and removes its
carrier from the working channel. The format of that acknowledgement should be the same as
that described in § 2.5.1 except that the “end of sequence” signal should be BQ and:
– the chargeable duration of the call should be inserted in the “frequency/channel” field by
coding the three characters as hours, minutes, seconds, e.g. a chargeable duration of 6 min
and 50 s would be coded as 00 06 50;
– if the chargeable duration of the call is not available then the “frequency/channel” field
should contain three symbols 126.
Note 1 – Some coast stations do not recognize this “end of call” DSC call or transmit the above
acknowledgement but rely solely on the procedures described in § 2.5.5.
2.5.3 If the coast station receives a second “end of call” DSC from the ship station within 4 s
then it should repeat the procedure given in § 2.5.2.
2.5.4 If the ship station does not receive an “end of call acknowledgement” within 2 s then it
should automatically repeat the “end of call”, then after a further 2 s or after receipt of an “end
of call acknowledgement” (whichever occurs first) it should consider the call to be complete and
remove the carrier from the working channel.
2.5.5 If the coast station does not receive the “end of call” as described in § 2.5.1, then the
call will be considered to be complete when the “on-hook” condition is detected from the PSTN
or if no reply within 1 min or loss of ship’s carrier for more than 5 s (duplex) or 45 s (simplex) is
detected (see § 2.4.2 to 2.4.4.2). When this indication is registered at the coast station, the
following action should take place:
– call timing is stopped;
– the line is cleared and disconnected from the radio circuit;
– the coast station transmits an “end of call” DSC call whose format is the same as that of the
acknowledgement described in § 2.5.2 except that the “end of sequence” signal should be
127;
– the coast station’s carrier is removed from the working channel.
Part C – Rec. ITU-R M.689-2 427
The radio channel is now free to handle other traffic.
2.5.6 If the ship station detects the absence of the coast station’s carrier for a period greater
than 5 s, then it should cease to transmit on the working channel. If further calls are required by
the ship then a new call should be initiated on the DSC calling channel.
3. Operational procedures in the shore-to-ship direction
3.1 Coast station initiates call
3.1.1 The equipment of a VHF coast station should provide the capability to distinguish the
ship’s identity, in accordance with Recommendation ITU-R M.585, when transmitted from the
PSTN.
3.1.2 When receiving a call request from the PSTN and if there is a working channel
available, the coast station equipment should radiate an engaged channel signal on the coast
station transmit frequency of that working channel.
3.1.3 If the coast station cannot comply immediately with the call request because no
working channel is available, then it should transmit a busy signal to the calling subscriber.
3.1.4 If there is a working channel available and a ship’s identity is detected in accordance
with § 3.1.1, the coast station should transmit a calling sequence on the DSC calling channel in
accordance with the following conditions:
– the format specifier will be 123 (automatic/semi-automatic service),
– the address will be that of the ship,
– the category will be 100 (routine),
– the self-identification will be that of the coast station,
– the first telecommand will be 101 (duplex F3E/G3E) or 100 (simplex F3E/G3E) or 106
(data) (see Note 1) and second telecommand as appropriate,
– the working channel number will be included,
– the PSTN subscriber number may follow if known,
– the “end of sequence” signal will be RQ.
Note 1 – Duplex mode of operation should be used for data communications.
3.1.5 If the coast station has not received an error-free acknowledgement from the called
ship station (see § 3.2) within 5 s, the calling sequence should be repeated automatically. If an
error-free acknowledgement of the repeated call is not received within the following 5 s, the call
is regarded as not started. The engaged channel signal is then removed and a busy signal is
transmitted to the calling subscriber for 5 s, after which the line is cleared.
428 Maritime Manual
3.2 Ship station acknowledgement
3.2.1 On receipt of an error-free calling sequence in accordance with § 3.1.4, the ship station
should, within 3 s of receiving it, automatically initiate the transmission of an acknowledgement
sequence on the DSC calling channel.
3.2.2 If the ship station can comply immediately with the call request, the acknowledgement
sequence should contain the same information as in the call request (§ 3.1.4), with the following
exceptions:
– the address will be that of the coast station,
– the self-identification will be that of the ship,
– the first and second telecommands will be as appropriate,
– the “end of sequence” signal will be BQ.
3.2.3 If the ship station cannot comply immediately with the call request, the
acknowledgement sequence should be as in § 3.2.2, except that the first telecommand should be
104 (unable to comply) and the second telecommand should be as appropriate to indicate the
reason for being unable to comply or symbol No. 126.
3.2.4 If the coast station receives an acknowledgement in accordance with § 3.2.2 then it
should transmit a ringing signal to the calling subscriber.
3.2.5 If the coast station receives an acknowledgement in accordance with § 3.2.3 then it
should remove the engaged channel signal and transmit a busy signal to the calling subscriber
for 5 s and then release the line.
3.3 Procedures subsequent to the exchange of initial DSC calls
3.3.1 If the ship station transmitted an acknowledgement in accordance with § 3.2.2 then it
should continue to listen to the calling channel for a further 5 s, and when the ship subscriber
indicates that he is able to accept the call (e.g. by lifting the handset) it should change to the
working channel and transmit a carrier as described in § 2.2.5. A DSC call, if contained within
that transmission, should be in accordance with § 3.2.2. If a further calling sequence in
accordance with § 3.1.4 is received within this 5 s period, the acknowledgement should be
repeated. If the ship subscriber does not accept the call within 1 min then the call should be
considered as not started and the procedures described in § 2.4.2 to 2.5.5 applied.
3.3.2 If the coast station does not receive a transmission on the working channel within
1 min, the call is regarded as not started, the carrier is removed from the working channel, and a
busy signal is transmitted to the calling subscriber for 5 s, after which the PSTN subscriber is
disconnected from the coast station.
3.4 Call connection
The coast station, on receipt of a transmission on the working channel in accordance
with § 3.3.1, should stop transmitting the ringing signal to the calling subscriber and begin
timing the call.
Part C – Rec. ITU-R M.689-2 429
3.5 Call completion
The procedures for completion of the call should be as described in § 2.5, except that
indication of chargeable duration of the call in the “end of call” sequence to the ship may be
omitted.
APPENDIX 1*
Timing diagram of call set-up sequences when the ship station
initiates the call
Coast station able to comply Coast station unable to comply (busy)
Time
(s)
Ship Coast station Ship Coast station
0 Initiate call (§ 2.1.2) Initiate call (§ 2.1.2)
1 . . . . . . . . . . . . . . . . . . . . Receive call and
radiate engaged
channel signal
(§ 2.2.2)
Receive call
2
3
4 . . . . . . . . . . . . . . . . . . . . Initiate
acknowledgement
(able) (§ 2.2.2)
Initiate
acknowledgement
(unable) (§ 2.2.3 and
2.2.4)
Store ship ID and
telephone number
(§ 2.3.2.1) if “ring back”
procedure
5 Receive
acknowledgement
(§ 2.2.5) {or initiate 2nd
call (§ 2.1.3)}
Receive
acknowledgement and
continue monitoring
DSC channel (§ 2.2.4)
{or initiate 2nd call
(§ 2.1.3)}
6 . . . . . . . . . . . . . . . . . . . . {Receive 2nd call (and
radiate engaged
channel signal if 1st
call not received –
§ 2.2.2)}
{Receive 2nd call}
7
8
9 . . . . . . . . . . . . . . . . . . . . {Initiate
acknowledgement due
to 2nd call (§ 2.3.1.2
and § 2.2.2)}
{Initiate
acknowledgement due to
2nd call (§ 2.3.1.2,
§ 2.2.2.3 and § 2.2.2.4)}
_______________
* This timing diagram is only applicable to fully automated ship station equipment that operate with coast
stations employing DSC signalling on the working channels.
430 Maritime Manual
Coast station able to comply Coast station unable to comply (busy)
Time
(s)
Ship Coast station Ship Coast station
10 Transmit carrier and DSC
call on working channel
(§ 2.2.5)
{or receive “2nd”
acknowledgement}
{Receive “2nd”
acknowledgement and
continue monitoring
DSC channel (§ 2.2.6)}
11 . . . . . . . . . . . . . . . . . . . . Recognize DSC call
then dial (§ 2.3.1.1)
12
13
14
15 {If not already done so,
transmit carrier and DSC
call on working channel
(§ 2.2.5)}
16 . . . . . . . . . . . . . . . . . . . . {If not already done so,
recognize DSC call then
dial (§ 2.3.1.1)}
17 . . . . . . . . . . . . . . . . . . . . {If no DSC call
recognized, remove
engaged channel signal
and delete calling record
(§ 2.3.1.2)}
=
=
< = 15 min . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
If working channel
available then radiate
engaged channel signal
on working channel and
transmit DSC “ring-
back” call (§ 2.3.2.2)
5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Receive “ring-back”
call
6
7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Transmit “ring-back”
acknowledgement
(§ 2.3.2.4)
8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Receive “ring-back”
acknowledgement
9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . {Initiate 2nd “ring-back”
call (§ 2.3.2.3)}
10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . {Receive 2nd “ring-
back” call}
11
12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Transmit carrier and
DSC call on working
channel {and transmit
acknowledgement due
to 2nd call} (§ 2.3.2.5)
Part C – Rec. ITU-R M.689-2 431
Coast station able to comply Coast station unable to comply (busy)
Time
(s)
Ship Coast station Ship Coast station
13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Recognize DSC call
then dial (§ 2.3.2.6)
{and receive “2nd”
“ring-back”
acknowledgement}
14
15
16
17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . {If not already done
so, transmit carrier and
DSC call on working
channel due to 2nd call
(§ 2.3.2.5)}
18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . {If not already done so
recognize DSC call then
dial (§ 2.3.2.6) or, if no
DSC call and
acknowledgement,
remove engaged channel
signals and clear call
details (§ 2.3.2.3)}
Timing diagram of call set-up sequences when the coast station
initiates the call
Time
(s)
Coast station Ship station
0 Transmit DSC call on calling channel (§ 3.1.4) and
engaged channel signal on the reserved working
channel (§ 3.1.2)
1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Receive call on calling channel (§ 3.2.1)
4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Initiate acknowledgement able (§ 3.2.2) or unable
(§ 3.2.3)
5 Receive acknowledgement on calling channel
If able, transmit ringing signal to the calling subscriber
(§ 3.2.4)
If unable, remove the engaged channel signal and
transmit a busy signal to the calling subscriber (§ 3.2.5)
6 {Transmit 2nd call if error-free acknowledgement not
received (§ 3.1.5)}
7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . {Receive 2nd call (§ 3.3.1)}
10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . {Transmit 2nd acknowledgement (§ 3.3.1)}
11 {Receive 2nd acknowledgement (§ 3.3.1)}
If error-free acknowledgement still not received,
remove the engaged channel signal and transmit a busy
signal to the calling subscriber (§ 3.2.5)
432 Maritime Manual
Time
(s)
Coast station Ship station
≤ 71 Lift handset and transmit within 5 s on working
channel (§ 3.3.1)
76 Receive call on working channel (§ 3.4). Connect radio
path to the calling subscriber. If no call received,
remove the engaged channel signal, transmit a busy
signal to the calling subscriber and release the line
(§ 3.3.2)
Note 1 – Timing diagram assumes 1 s between call initiation and reception and assumes maximum timing
between calls and acknowledgements.
Note 2 – Sequences in parentheses { . . . } are only applicable if repeat calls or acknowledgements are
necessary.
ANNEX 2
Technical characteristics
1. Ship station
1.1 The DSC equipment should meet the VHF technical characteristics detailed in
Recommendation ITU-R M.493, Annexes 1 or 2. This equipment need not necessarily provide
all combinations of codes, e.g. it may be simplified DSC equipment (with no distress functions),
but it must provide all the necessary formats for automatic/semi-automatic VHF DSC signalling.
1.2 The VHF transceiver should be capable of operating on all public correspondence
working channels listed in RR Appendix 18 and on the DSC calling channel and be capable of
automatic channel selection and carrier transmission under control of the DSC equipment.
1.3 The equipment should be capable of sensing the presence of a signal on the DSC
calling channel (see RR Appendix 19).
1.4 After initiation of a DSC call, the equipment should be capable of automatic
prevention of the transmission of that call, when the calling channel is occupied by calls (see RR
Appendix 19).
1.5 The equipment should be capable of operating in accordance with the operational
procedures described in Annex 1.
2. Coast station
2.1 The DSC equipment should meet the VHF technical characteristics detailed in
Recommendation ITU-R M.493, Annex 1. The installation should be capable of receiving and
transmitting all types of VHF DSC calls on the DSC calling channel.
Part C – Rec. ITU-R M.689-2 433
2.2 The VHF installation should be capable of operating in full duplex mode on the coast
station’s designated public correspondence working channels and in simplex mode on the DSC
calling channel.
2.3 After initiation of a DSC call, the equipment should be capable of automatic
prevention of the transmission of that call when the calling channel is occupied by calls (see RR
Appendix 19).
2.4 The coast station equipment should be capable of detecting the presence of a DSC call
on a working channel and also the line subscriber’s “off-hook” and “on-hook” conditions.
2.5 The coast station should be capable of radiating an “engaged channel” signal on any of
its working channels which should be dissimilar from any present line signalling tones.
2.6 The equipment should be capable of operating in accordance with the operational
procedures described in Annex 1.
434 Maritime Manual
RECOMMENDATION ITU-R SM.1138-2
Determination of necessary bandwidths including examples
for their calculation and associated examples for
the designation of emissions
(1995-2007-2008)
Annex 1
Determination of necessary bandwidths, including examples for their
calculation and associated examples for the designation of emissions
1 The necessary bandwidth is not the only characteristic of an emission to be
considered in evaluating the interference that may be caused by that emission.
2 In the formulation of the table, the following terms have been employed:
Bn: necessary bandwidth (Hz)
B: modulation rate (Bd)
N: maximum possible number of black plus white elements to be transmitted
per second, in facsimile
M: maximum modulation frequency (Hz)
C: sub-carrier frequency (Hz)
D: peak deviation, i.e. half the difference between the maximum and
minimum values of the instantaneous frequency. The instantaneous
frequency (Hz) is the time rate of change in phase (rad) divided by 2π
t: pulse duration (s) at half-amplitude
tr: pulse rise time (s) between 10% and 90% amplitude
K: an overall numerical factor which varies according to the emission and
which depends upon the allowable signal distortion. In the case of
orthogonal frequency division multiplexed multi-carrier signal, K is the
number of active sub-carriers as defined by equation (52) in
Recommendation ITU-R SM.328
Nc: number of baseband channels in radio systems employing multichannel
multiplexing
Part C – Rec. ITU-R SM.1138-2 435
fp: continuity pilot sub-carrier frequency (Hz) (continuous signal utilized to
verify performance of frequency-division multiplex systems)
Ns: frequency separation between two sub-carriers (kHz).
Description
of emission
Necessary bandwidth Designation
of emission Formula Sample calculation
I. NO MODULATING SIGNAL
Continuous wave
emission
– – NONE
II. AMPLITUDE MODULATION
1. Signal with quantized or digital information
Continuous wave
telegraphy, Morse code
Bn = BK
K = 5 for fading
circuits
K = 3 for non-fading
circuits
25 words per minute
B = 20, K = 5
Bandwidth: 100 Hz
100HA1AAN
Telegraphy by on-off
keying of a tone
modulated carrier,
Morse code
Bn = BK + 2M
K = 5 for fading
circuits
K = 3 for non-fading
circuits
25 words per minute
B = 20, M = 1 000, K = 5
Bandwidth: 2 100 Hz = 2.1 kHz
2K10A2AAN
Selective calling signal
using sequential single
frequency code, single-
sideband full carrier
Bn = M Maximum code frequency is:
2 110 Hz
M = 2 110
Bandwidth: 2 110 Hz = 2.11 kHz
2K11H2BFN
Direct-printing
telegraphy using a
frequency shifted
modulating sub-carrier,
with error-correction,
single-sideband,
suppressed carrier
(single channel)
Bn = 2M + 2DK
2
BM =
B = 50
D = 35 Hz (70 Hz shift)
K = 1.2
Bandwidth: 134 Hz
134HJ2BCN
Telegraphy,
multichannel with
voice frequency,
error-correction, some
channels are time-
division multiplexed,
single-sideband,
reduced carrier
Bn = highest central
frequency + M + DK
2
BM =
15 channels;
highest central frequency is:
2 805 Hz
B = 100
D = 42.5 Hz (85 Hz shift)
K = 0.7
Bandwidth: 2 885 Hz = 2.885 kHz
2K89R7BCW
2. Telephony (commercial quality)
Telephony,
double-sideband
(single channel)
Bn = 2M M = 3 000
Bandwidth: 6 000 Hz = 6 kHz
6K00A3EJN
436 Maritime Manual
Description
of emission
Necessary bandwidth Designation
of emission Formula Sample calculation
2. Telephony (commercial quality)
Telephony, single-
sideband,
full carrier (single
channel)
Bn = M M = 3 000
Bandwidth: 3 000 Hz = 3 kHz
3K00H3EJN
Telephony, single-
sideband,
suppressed carrier
(single channel)
Bn = M – lowest
modulation frequency
M = 3 000
lowest modulation frequency =
300 Hz
Bandwidth: 2 700 Hz = 2.7 kHz
2K70J3EJN
Telephony with
separate frequency
modulated signal to
control the level of
demodulated speech
signal, single-sideband,
reduced carrier
(Lincompex) (single
channel)
Bn = M Maximum control frequency =
2 990 Hz
M = 2 990
Bandwidth: 2 990 Hz = 2.99 kHz
2K99R3ELN
Telephony with
privacy, single-
sideband, suppressed
carrier (two or more
channels)
Bn = Nc M – lowest
modulation frequency
in the lowest channel
Nc = 2
M = 3 000
lowest modulation frequency =
250 Hz
Bandwidth: 5 750 Hz = 5.75 kHz
5K75J8EKF
Telephony,
independent sideband
(two or more channels)
Bn = sum of M for each
sideband
2 channels
M = 3 000
Bandwidth: 6 000 Hz = 6 kHz
6K00B8EJN
3. Sound broadcasting
Sound broadcasting,
double-sideband
Bn = 2M
M may vary between
4 000 and 10 000
depending on the
quality desired
Speech and music
M = 4 000
Bandwidth: 8 000 Hz = 8 kHz
8K00A3EGN
Sound broadcasting,
single-sideband,
reduced carrier (single
channel)
Bn = M
M may vary between
4 000 and 10 000
depending on the
quality desired
Speech and music
M = 4 000
Bandwidth: 4 000 Hz = 4 kHz
4K00R3EGN
Sound broadcasting,
single-sideband,
suppressed carrier
Bn = M – lowest
modulation frequency
Speech and music
M = 4 500
lowest modulation frequency =
50 Hz
Bandwidth: 4 450 Hz = 4.45 kHz
4K45J3EGN
Part C – Rec. ITU-R SM.1138-2 437
Description
of emission
Necessary bandwidth Designation
of emission Formula Sample calculation
4. Television
Television, vision and
sound
Refer to relevant
ITU-R documents for
the bandwidths of the
commonly used
television systems
Number of lines: 625
Nominal video bandwidth = 5 MHz
Sound carrier relative to
video carrier: 5.5 MHz
Total vision Bandwidth: 6.25 MHz
FM sound bandwidth including
guardbands: 750 kHz
RF channel Bandwidth: 7 MHz
6M25C3F --
750KF3EGN
5. Facsimile
Analogue facsimile by
sub-carrier frequency
modulation of a single-
sideband emission with
reduced carrier,
monochrome
Bn = C + 2
N + DK
K = 1.1
(typically)
N = 1 100 corresponding to an index
of cooperation of 352 and a cycler
rotation speed of 60 rpm. Index of
cooperation is the product of the
drum diameter and number of lines
per unit length.
C = 1 900
D = 400 Hz
Bandwidth: 2 890 Hz = 2.89 kHz
2K89R3CMN
Analogue facsimile;
frequency modulation
of an audio frequency
sub-carrier which
modulates the main
carrier, single-sideband
suppressed carrier
Bn = 2M + 2DK
M = 2
N
K = 1.1
(typically)
N = 1 100
D = 400 Hz
Bandwidth: 1 980 Hz = 1.98 kHz
1K98J3C --
6. Composite emissions
Double-sideband,
television relay Bn = 2C + 2M + 2D Video limited to 5 MHz, audio on
6.5 MHz, frequency modulated
sub-carrier, sub-carrier deviation =
50 kHz:
C = 6.5 × 106
D = 50 × 103 Hz
M = 15 000
Bandwidth: 13.13 × 106 Hz
= 13.13 MHz
13M1A8W --
Double-sideband
radio-relay system,
frequency division
multiplex
Bn = 2M 10 voice channels occupying
baseband between 1 kHz and
164 kHz
M = 164 000
Bandwidth: 328 000 Hz = 328 kHz
328KA8E --
438 Maritime Manual
Description
of emission
Necessary bandwidth Designation
of emission Formula Sample calculation
6. Composite emissions
Double-sideband
emission of VOR with
voice
(VOR: VHF
omnidirectional
radio range)
Bn = 2Cmax + 2M +
2DK
K = 1
(typically)
The main carrier is modulated by:
– a 30 Hz sub-carrier
– a carrier resulting from a
9 960 Hz tone frequency modulated
by a 30 Hz tone
– a telephone channel
– a 1 020 Hz keyed tone for
continual Morse identification
Cmax = 9 960
M = 30
D = 480 Hz
Bandwidth: 20 940 Hz = 20.94 kHz
20K9A9WWF
Independent sidebands;
several telegraph
channels with error-
correction together
with several telephone
channels with privacy;
frequency division
multiplex
Bn = sum of M for each
sideband
Normally composite systems are
operated in accordance with
standardized channel arrangements
(e.g. Rec. ITU-R F.348).
3 telephone channels and
15 telegraphy channels require
the bandwidth:
12 000 Hz = 12 kHz
12K0B9WWF
7. Standard frequency and time signals
7.1 High frequency (voice)
Voice announcements,
double-sideband Bn = 2M Speech
M = 4 000
Bandwidth: 8 000 Hz = 8 kHz
8K00A3XGN
7.2. High frequency (time code)
Time code as
telegraphy Bn = BK + 2M B = 1/s
M = 1
K = 5
Bandwidth: 7 Hz
7H00A2XAN
7.3. Low frequency (time code)
Time code as
telegraphy Bn = BK + 2M B = 1/s
M = 1
K = 3
Bandwidth: 5 Hz
5H00A2XAN
Part C – Rec. ITU-R SM.1138-2 439
Description
of emission
Necessary bandwidth Designation
of emission Formula Sample calculation
III-A. FREQUENCY MODULATION
1. Signal with quantized or digital information
Telegraphy without
error-correction (single
channel)
Bn = 2M + 2DK
2
BM =
K = 1.2
(typically)
B = 100
D = 85 Hz (170 Hz shift)
Bandwidth: 304 Hz
304HF1BBN
Telegraphy, narrow-
band direct-printing
with error-correction
(single channel)
Bn = 2M + 2DK
2
BM =
K = 1.2
(typically)
B = 100
D = 85 Hz (170 Hz shift)
Bandwidth: 304 Hz
304HF1BCN
Selective calling signal Bn = 2M + 2DK
2
BM =
K = 1.2
(typically)
B = 100
D = 85 Hz (170 Hz shift)
Bandwidth: 304 Hz
304HF1BCN
Four-frequency duplex
telegraphy
Bn = 2M + 2DK
B: modulation rate
(Bd) of the faster
channel.
If the channels are
synchronized:
2
BM = (otherwise,
M = 2B)
K = 1.1
(typically)
Spacing between adjacent
frequencies = 400 Hz
Synchronized channels
B = 100
M = 50
D = 600 Hz
Bandwidth: 1 420 Hz = 1.42 kHz
1K42F7BDX
2. Telephony (commercial quality)
Commercial telephony Bn = 2M + 2DK
K = 1
(typically, but under
certain conditions a
higher value of K may
be necessary)
For an average case of commercial
telephony,
D = 5 000 Hz
M = 3 000
Bandwidth: 16 000 Hz = 16 kHz
16K0F3EJN
3. Sound broadcasting
Sound broadcasting Bn = 2M + 2DK
K = 1
(typically)
Monaural
D = 75 000 Hz
M = 15 000
Bandwidth: 180 000 Hz = 180 kHz
180KF3EGN
440 Maritime Manual
Description
of emission
Necessary bandwidth Designation
of emission Formula Sample calculation
4. Facsimile
Facsimile by direct
frequency modulation
of the carrier; black
and white
Bn = 2M + 2DK
2
NM =
K = 1.1
(typically)
N = 1 100 elements/s
D = 400 Hz
Bandwidth: 1 980 Hz = 1.98 kHz
1K98F1C --
Analogue facsimile Bn = 2M + 2DK
2
NM =
K = 1.1
(typically)
N = 1 100 elements/s
D = 400 Hz
Bandwidth: 1 980 Hz = 1.98 kHz
1K98F3C --
5. Composite emissions (see Table III-B)
Radio-relay system,
frequency division
multiplex
Bn = 2fp + 2DK
K = 1
(typically)
60 telephone channels occupying
baseband between 60 kHz and
300 kHz;
r.m.s. per-channel deviation:
200 kHz; continuity pilot at
331 kHz produces 100 kHz r.m.s.
deviation of main carrier.
D = 200 × 103 × 3.76 × 2.02
= 1.52 × 106 Hz
fp = 0.331 × 106 Hz
Bandwidth: 3.702 × 106 Hz
= 3.702 MHz
3M70F8EJF
Radio-relay system,
frequency division
multiplex
Bn = 2M + 2DK
K = 1
(typically)
960 telephone channels occupying
baseband between 60 kHz and
4 028 kHz; r.m.s. per-channel
deviation: 200 kHz;
continuity pilot at 4 715 kHz
produces 140 kHz r.m.s. deviation
of main carrier.
D = 200 × 103 × 3.76 × 5.5
= 4.13 × 106 Hz
M = 4.028 × 106
fp = 4.715 × 106
(2M + 2DK) > 2 fp
Bandwidth: 16.32 × 106 Hz =
16.32 MHz
16M3F8EJF
Part C – Rec. ITU-R SM.1138-2 441
Description
of emission
Necessary bandwidth Designation
of emission Formula Sample calculation
5. Composite emissions (see Table III-B)
Radio-relay system,
frequency division
multiplex
Bn = 2fp 600 telephone channels occupying
baseband between 60 kHz and
2 540 kHz;
r.m.s. per-channel deviation:
200 kHz;
continuity pilot at 8 500 kHz
produces
140 kHz r.m.s. deviation of main
carrier.
D = 200 × 103 × 3.76 × 4.36
= 3.28 × 106 Hz
M = 2.54 × 106
K = 1
fp = 8.5 × 106
(2M + 2DK) < 2 fp Bandwidth: 17 × 106 Hz = 17 MHz
17M0F8EJF
Stereophonic sound
broadcasting with
multiplexed subsidiary
telephony sub-carrier
Bn = 2M + 2DK
K = 1
(typically)
Pilot tone system;
M = 75 000
D = 75 000 Hz
Bandwidth: 300 000 Hz = 300 kHz
300KF8EHF
442 Maritime Manual
III-B. MULTIPLYING FACTORS FOR USE IN COMPUTING D,
PEAK FREQUENCY DEVIATION, IN FM FREQUENCY DIVISION
MULTIPLEX (FM-FDM) MULTI-CHANNEL EMISSSIONS
For FM-FDM systems the necessary bandwidth is:
Bn = 2M + 2DK
The value of D, or peak frequency deviation, in these formulae for Bn is calculated by multiplying the
r.m.s. value of per-channel deviation by the appropriate “multiplying factor” shown below.
In the case where a continuity pilot of frequency fp exists above the maximum modulation frequency M,
the general formula becomes:
Bn = 2fp + 2DK
In the case where the modulation index of the main carrier produced by the pilot is less than 0.25, and the
rms frequency deviation of the main carrier produced by the pilot is less than or equal to 70% of the r.m.s.
value of per-channel deviation, the general formula becomes either:
Bn = 2fp or Bn = 2M + 2DK
whichever if greater.
Multiplying factor(1)
Number of
telephone channels
Nc !"
#$%
&×
20
levelreferencemodulationabovedBinvalueantilog)factorPeak(
3 < Nc < 12
a value in dB specified by the equipment manufacturer or
station licensee, subject to administration approval 4.47 antilog
20×
& #$ !$ !$ !% "
12 ≤ Nc < 60 !"
#$%
& +×
20
log22.6antilog76.3 cN
Multiplying factor(2)
Number of
telephone channels
Nc !"
#$%
&×
20
levelreferencemodulationabovedBinvalueantilog)factorPeak(
60 ≤ Nc < 240 !"
#$%
& +×
20
log4–1antilog76.3 cN
Nc ≥ 240 !"
#$%
& +×
20
log01–15antilog76.3 cN
(1) In the above chart, the multipliers 3.76 and 4.47 correspond to peak factors of 11.5 and 13.0 dB,
respectively.
(2) In the above chart, the multipliers 3.76 correspond to peak factors of 11.5 dB.
Part C – Rec. ITU-R SM.1138-2 443
Description
of emission
Necessary bandwidth Designation
of emission Formula Sample calculation
IV. PULSE MODULATION
1. Radar
Unmodulated pulse
emission t
KBn
2=
K depends upon the
ratio of pulse duration
to pulse rise time. Its
value usually falls
between 1 and 10 and
in many cases it does
not need to exceed 6
Primary radar
range resolution = 150 m
K = 1.5 (triangular pulse
where t ~ tr,
only components down to 27 dB
from the strongest are considered)
Then:
!"
#$%
& ×=
lightofvelocity
)resolution(range2t
810 3
150 2
×
×=
= 1 × 10–6 s
Bandwidth: 3 × 106 Hz = 3 MHz
3M00P0NAN
2. Composite emissions
Radio-relay system
t
KBn
2=
K = 1.6
Pulse position modulated by 36
voice channel baseband; pulse
width at half amplitude = 0.4 µs
Bandwidth: 8 × 106 Hz = 8 MHz
(Bandwidth independent of the
number of voice channels)
8M00M7EJT
3. Standard frequency and time signals
3.1 High frequency (tone bursts)
Ticks used for
epoch measurement
Bn = 2/tr tr = 1 ms
Bandwidth: 2 000 Hz = 2 kHz
2K00K2XAN
3.2 Low frequency (time code)
Time code leading
edge used for epoch
measurement
Bn = 2/tr tr = 1 ms
Bandwidth = 2 000 Hz = 2 kHz
2K00K2XAN
V. MISCELLANEOUS
Orthogonal
frequency division
multiplexing
(OFDM) or coded
OFDM (COFDM)
Bn = Ns·K 53 active sub-carriers are used,
each spaced 312.5 kHz apart
(K = 53 and Ns = 312.5 kHz). Data
sub-carriers can be BPSK, QPSK,
QAM modulated
Bn = 312.5 kHz × 53 = 16.6 MHz
16M6W7D
444 Maritime Manual
RECOMMENDATION ITU-R M.1467-1
Prediction of sea area A2 and NAVTEX ranges and protection
of the A2 global maritime distress and safety
system distress watch channel
(Question ITU-R 92/8)
(2000-2006)
Annex 1
Prediction of A2 and NAVTEX ranges
1 Overview
In order to establish a new A2 sea area it is necessary to account for variations in the
propagation conditions. A2 coverage is by groundwave, which is largely stable,
enabling the extent of the service area to be confirmed by measurement, as is
recommended by the IMO, before committing capital expenditure.
The design criteria to be used for establishing A2 and NAVTEX sea areas are defined
by the IMO in Annex 3 to their Resolution A.801(19).
2 Prediction of A2 and NAVTEX ranges
2.1 IMO performance criteria
The criteria developed by the IMO for determination of A2 and NAVTEX ranges are
reproduced in Table 1 and should be used in the determination of ranges for A2 and
NAVTEX services.
Part C – Rec. ITU-R M.1467-1 445
TABLE 1
Performance criteria for A2 and NAVTEX transmissions
2.2 Achieving the required quality of signal
2.2.1 The effect of received noise
On a very quiet site, man-made noise dominates below 4 MHz and galactic noise
above. These combine, at the receive antenna with seasonal levels of atmospheric noise,
and also transmitter sideband noise, as shown in Fig. 1. Recommendation ITU-R P.372
should be used to account for atmospheric and normal man-made noise levels.
Distress channel Radiotelephony DSC ARQ NBDP NAVTEX
Frequency (kHz) 2 182 2 187.5 2 174.50 490 and 518
Bandwidth (Hz) 3 000 300 300 300
Propagation Groundwave Groundwave Groundwave Groundwave
Ship’s power (W) 60 60 60
Ship’s antenna efficiency
(%)
25 25 25 25
RF full bandwidth signal/
noise ratio (S/N) (dB)
9 12 18 min(1) 8
Mean Tx power below
peak (dB)
8 0 0 0
Fading margin (dB) 3 Not stated 3
IMO reference for above Res. A.801(19) Res. A.804(19) Rec. ITU-R F.339 Res. A.801(19)
Availability required (%) 95(2) Not stated Not stated 90
DSC: digital selective calling
NBDP: narrow-band direct printing
(1) Stated as 43 dB(Hz) under stable and 52 dB(Hz) under fading conditions with 90% traffic efficiency.
(2) Availability can be relaxed to 90% in cases where the noise data used or performance achieved can be proven by
measurement.
446 Maritime Manual
Paragraph 3.5 should be used to ensure that the levels of transmitter sideband noise and
intermodulation products reaching the receive antenna by groundwave do not exceed
the tolerable limit for protection of the A2 DSC watch frequency.
2.2.2 C/N required for single sideband (SSB) radiotelephony
In order to maintain the intelligibility of a received SSB radiotelephony signal it is
necessary to provide the operator with a minimum AF signal/noise plus distortion ratio
(SINAD), which in turn defines the RF C/N required at the receive antenna.
The capture range for an A2 receive system should be calculated assuming an RF C/N
density figure of 52 dB(Hz) at the shore-based receive antenna. This will ensure that a
ship’s transmitter operating with a peak-to-mean ratio of 8 dB provides the shore-based
operator with a 9 dB S/N in a 3 000 Hz bandwidth, as stipulated by the IMO.
The receive antenna and multicoupler should be designed to offer good linearity to
minimize the risk of intermodulation products being generated on the watch
frequencies. With good electronic design the noise generated within the receive system
itself can be ignored below 3 MHz.
2.2.3 C/N required for NAVTEX broadcasts
The transmit range for NAVTEX broadcasts should be calculated assuming an RF C/N
density figure of 35 dB(Hz) at the ship’s antenna. This will ensure that the NAVTEX
receiver is provided with an RF S/N of 8 dB in a 300 Hz bandwidth.
Part C – Rec. ITU-R M.1467-1 447
2.3 Accounting for ships topside noise
Topside noise refers to the environmental noise generated by ship-borne machinery,
and other sources, and a figure is required for entry into NOISEDAT and other
programs. Table 2 shows a number of published figures, and for reference purposes
includes galactic and quasi-minimum noise levels, which is accepted as representing the
best achievable noise floor.
TABLE 2
Naval environmental categories for topside noise
The Australian Department of Defence (DOD) and Advisory Group for Aeronautical
Research and Development (AGARD) have both published relevant figures. The
AGARD figure represents a naval vessel under normal cruise conditions, whilst the
DOD figure represents the maximum level under battle conditions with all machinery in
operation.
The levels of noise to be expected on commercial vessels can be expected to range
between these figures. The IPS Radio and Space Services (IPS) of the Australian
Department of Industry have adopted an intermediate figure in their GWPS, which is
well accepted as representing the noise level encountered on container vessels, pleasure
cruisers, and utility ships. This figure, !142 dBW, should be used in prediction of
coverage area of shore-based GMDSS transmitters.
2.4 Determination of external noise factor, Fa, for the required availability
An A2 area in the GMDSS is defined as the area within which ship stations can alert
shore stations by using DSC on MF and communicate with the shore stations using MF
radiotelephony (class of emission J3E). The communications ranges for voice signals
are shorter than for DSC and the IMO criteria for determination of A2 areas should
therefore be based on the communication of voice signals.
Environmental category dB below 1 W
ref. 3 MHz
DOD Cat 1 mobile platform !137.0
IPS ship (ASAPS and GWPS) !142.0
AGARD ship !148.0
Quasi-minimum noise !156.7
Noise galactic (Rec. ITU-R P.372) !163.6
ASAPS: advanced stand alone prediction system
GWPS: groundwave prediction system
448 Maritime Manual
The range achieved by a transmitter or a receiver depends upon the radiated power, the
propagation loss, and the ability of the receiver to discriminate between the wanted
signal and the unwanted noise or interference. The level of each component in the
received signal will drift as the propagation conditions change with time, and therefore
arrive at the receive antenna in varying proportions. The final system design should
therefore ensure that the level of the signal will exceed the level of the noise by an
adequate amount for an adequate proportion of the time. This proportion is called the
availability, and is determined by quantifying the behaviour of the signal and the noise
with time as shown in Fig. 2.
Equation (1) should be used to calculate an upper value Fa for the external noise factor
which corresponds to the required availability:
22stama DDFF ++= dB above k T0 B (1)
Part C – Rec. ITU-R M.1467-1 449
where:
Fam : median external noise factor
Ds : variation in signal level expected for the required time
percentage, to which is ascribed the figure of 3 dB specified by
the IMO as fading margin
Dt : variation in noise level expected for the required percentage of
time.
90% availability is required for NAVTEX broadcasts, and so the upper decile value Du
should be substituted for Dt in equation (1).
95% availability is required for A2 coverage. To achieve this, substitute Dt = Du + 3 dB
in equation (1).
First Fam and Du should be determined by running the Noise1 program, which comes
with the ITU NOISEDAT package. The program requests seasons required, site
location, frequency, level or category of man-made noise, and type of data output
required (select Fa), local mean time, and statistical parameters required (select overall
median). For prediction of external noise factor on ship stations, the reference figure of
!142 dBW should be used to account for topside noise, if no better data is available.
The data is presented in seasonal blocks as shown in Table 3, the data fields being
explained in Table 4.
TABLE 3
Sample NOISEDAT output
LAT = –51.45, LONG = –57.56, DUMMY SITE
WINTER FMHZ = 2.182, QUIET RURAL NOISE
OVERALL NOISE
TIME BLOCK ATMO GAL MANMADE OVERALL DL DU SL SM SU
0000-0400 59.3 44.2 43.9 59.6 7.2 9.2 2.3 3.5 2.6
0400-0800 54.0 44.2 43.9 54.5 4.1 1.9 3.2 3.4 2.7
0800-1200 28.2 44.2 43.9 45.9 4.3 9.0 2.2 3.4 1.3
1200-1600 31.0 44.2 43.9 46.0 4.2 8.9 2.2 3.3 1.3
1600-2000 53.5 44.2 43.9 53.9 10.4 12.2 3.6 3.9 2.9
2000-2400 54.3 44.2 43.9 55.2 7.2 9.2 2.3 3.7 2.6
450 Maritime Manual
TABLE 4
Fields presented for use in the NOISEDAT output
The median and upper values for Fa should be organized as shown in Table 5, and the
seasonal spread in the value of Fa for the required availability should be plotted as a
bar graph in Fig. 3. This presentation enables the process to be reviewed if any
anomalies occur.
TABLE 5
External noise factor, Fa
Field Symbol Description
TIME BLOCK Time block during which original measurements were made
ATMO Level of atmospheric component
GAL Level of galactic component
MANMADE Level of man-made component
OVERALL Fam Median level of Fa
DL Dl Lower decile of deviation from median
DU Du Upper decile of deviation from median
SL " Dl Standard deviation of Dl
SM " Fam Standard deviation of Fam
SU " Du Standard deviation of Du
Median value, Fam
Fa for required availability
stam DDF 22 ++
Time block Winter Spring Summer Autumn Winter Spring Summer Autumn
0000-0400 59.6 55.9 52 52.2 71.7 65.2 60.2 60.9
0400-0800 54.5 43.7 45.9 46 66.8 56.2 55.6 59.5
0800-1200 45.9 45.9 45.8 45.9 55.4 55.4 55.3 55.4
1200-1600 46 41.9 37.7 45.8 55.4 54.8 52.5 55.7
1600-2000 53.9 43.2 43.6 43.9 66.5 59.7 59.5 58.2
2000-2400 55.2 55 54.4 55.8 64.9 63.2 61.4 64.3
Part C – Rec. ITU-R M.1467-1 451
IMO Resolution A.801(19) states “Administrations should determine time-periods and
seasons appropriate to their geographic area based on prevailing noise levels”.
2.5 Accounting for propagation by groundwave
2.5.1 Introduction
Horizontally polarized waves will not propagate along the surface of normal ground, as
the electric vector runs tangential to the surface causing a current to flow, which results
in absorption and heavy transmission losses. For this reason groundwaves have to be
vertically polarized, and can only be generated by a vertical antenna, or to a limited
extent by an antenna which is not perfectly horizontal, either because one end is higher
than the other, or because the elements droop.
The prime mover for groundwave propagation is the cymomotive force (c.m.f.) exerted
by the transmit antenna. In free space, power flux-density (W/m2) decreases inversely
with the square of distance, and so the field strength decreases inversely with distance
and has a value equal to the product of c.m.f. and distance. The c.m.f. is synonymous
with the effective monopole radiated power (e.m.r.p.), which is the power (kW) which
452 Maritime Manual
would have to be fed into a short lossless monopole to achieve the same c.m.f., and in
dB terms the two have the same value. A short lossless monopole on a perfect ground
fed with 1 kW has a c.m.f. of 300 V, which is the reference used in the groundwave
curves given in Recommendation ITU-R P.368.
Subsequent calculation of the transmitter power required should take account of the
following losses associated with the antenna:
– the transmitter output power may be de-rated by an antenna offering a poor
match;
– power will be absorbed by the ground and the feeder;
– whereas an ideal monopole will produce maximum radiation along the ground,
the radiation from a real antenna will peak a few degrees above the ground and
tuck in to a lower value along the ground.
2.5.2 Proof of performance tests
IMO Resolution A.801(19) stipulates that the range of the A2 sea area should be
verified by field strength measurement. The c.m.f. of any shore-based transmitter and
antenna should therefore be determined by operating the transmitter continuously at
peak power, and measuring the resulting field strength using a portable field strength
meter. This should be done on an arc around the station with an approximate radius of
1 km in the required directions of propagation. The precise location of the antenna and
each measurement point should be fixed using a GPS navigator. The c.m.f. on each
bearing is then the product of field strength (mV/m) and range (km) for each
measurement point. The antenna drive point current should also be recorded before and
after the measurement.
The procedures in this Recommendation should be used by administrations to
determine the c.m.f. required to establish coverage, which should then be demonstrated
by the equipment supplier, effectively eliminating uncertainties in performance due to
local ground conditions, and the antenna and station earthing system.
2.5.3 Determination of extent of A2 service area
The extent of the A2 service area is determined by the range over which SSB
communication is effective at 2 182 kHz between ship and shore. The ship is considered
to be fitted with a 60 W transmitter, feeding a short monopole antenna with an
efficiency of 25%, as given in Table 1.
The range is fixed by the maximum distance at which the ship can be from the shore
station to produce an S/N of 9 dB in a 3 kHz bandwidth out of the receive antenna at the
shore station. The shore transmit station must transmit sufficient power to return the
same S/N at the output of the ship’s receive antenna.
Part C – Rec. ITU-R M.1467-1 453
The range in both directions depends upon the sensitivity of the receive antenna, which
depends upon the levels of natural and man-made noise present, and the ability of the
antenna to discriminate between the wanted signal and the unwanted radiated noise.
Although some improvement can be achieved by using a directional receive antenna,
this often proves to be uneconomic and impractical, and is outside the scope of this
Recommendation. It will be assumed that a short whip antenna is used for reception,
that it has been installed on clear ground on an earth mat, and that it is regularly
maintained to avoid the effects of corrosion. The noise factor of the receive system
connected to the antenna can be ignored at 2 182 kHz.
2.5.3.1 Determination of shore-based receive range
The IMO minimum range thus achieved should be determined for all seasonal values of
Fa using the 15 W curve in Fig. 4. Additional curves have been included to demonstrate
the benefit of vessels using higher transmit powers.
454 Maritime Manual
2.5.3.2 Determination of shore-based transmit power required
Effective two-way SSB radiotelephony requires matched conditions in both directions.
Since the transmission loss is the same in both directions the power required to return a
call depends primarily upon the difference in noise levels at each end, and also the
difference in transmit antenna efficiency. However the following additional factors
have a direct impact on the power to be transmitted by the shore station:
– peaks and troughs in the radiation pattern of the receive antenna on the ship,
due to interaction with the ship’s hull;
– losses due to the condition of the ship’s receive antenna on the ship.
Tests on scale models of a number of vessels indicate that variability in gain of receive
antennas is typically ±5 dB. Furthermore, allowance should be made for ships whose
antennas are in poorly maintained condition. A figure of 10 dB has been included in the
calculation of shore-ship power budget to take account of these factors.
To determine the radiated power required from the shore-based transmitter the external
noise factors for the receive stations on shore, Fac, and ship, Fas, should first be
established as described in § 2.4. The minimum e.m.r.p. required to return a GMDSS
call at the same S/N to a ship on the limit of the service area should then be calculated
using equation (2):
Pe.m.r.p. = (Fas – Fac) –16 + Rpm dB(kW) (2)
where:
Rpm: peak-to-mean ratio of the transmitter used on the shore station
(dB).
The transmitter power required, PTx, should then be determined from equation (3), in
which La should account for all the losses associated with the antenna described in
§ 2.5.1:
PTx = Pe.m.r.p. + La (3)
Substituting typical figures (Fas – Fac) = 10 dB, Rpm = 3 dB, and La = 3 dB yields a
typical value of 1 000 W for the minimum required transmitter power at the coast
station.
If the antenna efficiency Effant is required it should then be determined from
equation (4):
Effant = Pe.m.r.p./PTx (4)
Part C – Rec. ITU-R M.1467-1 455
2.5.4 Determination of the range achieved using NAVTEX operation
The range achieved by a given NAVTEX transmitter depends upon the efficiency of the
transmit antenna, and the external noise factor on board the ship, as shown in Fig. 5.
The antenna efficiency depends upon the quality of the Earth system provided, and
once the required c.m.f. has been determined, it should be measured as described in
§ 2.5.2, and the efficiency determined.
456 Maritime Manual
IMO Resolution A.801(19) specifies 90% availability and so the upper decile value for
Fa should be calculated using the statistical data produced by NOISEDAT.
3 Protection of A2 watch frequency
The IMO specify that the distress channels should be watched 24 h per day. The system
should be designed so that the watch function is not desensitized by noise or
interference. It is essential therefore that all transmit channels assigned for use on the
transmitting station are selected so that no intermodulation products are allowed to fall
within the frequency bands of the watch channels.
For very close channel separations the watch process can be threatened by energy in
upper sideband of the adjacent SSB transmission falling within the receiver passband,
where the wanted signal could be swamped by blocking or reciprocal mixing. Where
channel separation is large enough to remove the threat of reciprocal mixing, a further,
but lesser threat to the watch process may be sideband noise from the transmitter falling
in the receiver passband.
The resulting DSC signal level reaching the shore station will depend upon the declared
A2 range for the shore station, and in turn depend upon the sensitivity, Fa.
The level to be protected would be the level reaching the shore station after suffering a
3 dB fading loss, and is shown in Fig. 6.
Part C – Rec. ITU-R M.1467-1 457
3.1 Impact of site separation on system performance
3.2 Estimating the level of the interference field
The tolerable amount of sideband noise leaving the transmit antenna, and the level of
adjacent channel isolation required by the watch receiver both depend upon the
separation between the transmit and receive antenna, and Fig. 7 provides a reference
power Pref (mW), which corresponds to the radiated power which would produce a field
strength at the receive antenna equal to the DSC field strength to be protected and Fig. 8
provides a rule of thumb to relate this to transmitter and receiver characteristics.
458 Maritime Manual
Part C – Rec. ITU-R M.1467-1 459
3.3 Required adjacent channel selectivity
The level of adjacent channel isolation required by the watch receiver depends upon the
separation between transmit and receive antennas. Figure 7 provides a reference power,
Pref, which corresponds to the radiated power which would produce a field strength at
the receive antenna equal to the DSC field strength to be protected. If the receiver has
an adjacent channel isolation figure of Iadj (dB), then the maximum power radiated by
the station should be limited to:
Prad = Pref + Iadj (5)
Three grades of receiver may be considered for providing the DSC watch: commercial
communications receivers, ship’s DSC watch receivers, or high performance
crystallized DSC watch receivers, conforming with Table 6:
TABLE 6
3.4 Protection from adjacent channel interference
The maximum permitted transmitter power should be determined using equation (6):
PTx = 30 + 10 log(Pref) + Iadj – 10 log(Effant) (6)
where:
PTx: transmitter power (dBW)
Iadj: adjacent channel isolation figure for the receiver
Effant: antenna efficiency.
For example, consider a receiver of the grade used on board ship having a typical
adjacent channel isolation figure of 60 dB, on a site offering an Fa of 65 dB located
2.5 km from a transmit antenna with an efficiency of 75%. Figure 7 gives a Pref of
0.1 mW and so the maximum level of radiated power would be 60 dB above 0.1 mW,
which is 100 W. Allowing for antenna efficiency the maximum transmitter power
would be 133 W. In order to benefit from a 500 W transmitter a pre-filter offering an
additional 4 dB adjacent channel isolation would be required.
Selectivity
(dB)
Offset
(Hz)
6 Between 150 and 220
30 Less than 270
60 Below 400
80 Less than 550
460 Maritime Manual
3.5 Protection from transmitter sideband noise
The maximum tolerable level of sideband noise is determined by the required C/N at
the receive antenna. In the above example, for a S/N of 10 dB, the maximum tolerable
level of sideband power would be 10 mW, which is quite low, and may call for use of a
post-selector to reduce the noise leaving the transmitter modulator unit.
3.6 Co-site operation
Figure 9 shows the effect of reducing the separation between the transmit and receive
antenna below 1 km to 300 m, the minimum value computed using GRWAVE. By way
of example, if a station close to the shoreline had a maximum annual median external
noise factor Fa of 65 dB then from Fig. 4 the range achieved would be just over
200 nautical miles. If the adjacent channel isolation were 80 dB, then for an e.m.r.p. of
200 W the antenna separation should be not less than 450 m.
Part C – Rec. ITU-R M.1467-1 461
Under such circumstances a long feeder would be required to attain the separation
required. As the frequency increases there is a considerable reduction in external noise
and increase in feeder loss. At 2 MHz the external noise factor is very much greater
than the system noise factor, and for a system noise factor of 15 dB up to 10 dB of
feeder loss would be tolerable on a well designed and maintained system. A cost-
effective way to avoid the cost of a very long low loss coaxial cable would be to use a
separate antenna for A2.
4 Software requirements
4.1 Noise calculation
To simplify the determination of range for A2 and NAVTEX transmissions a modified
form of NOISEDAT is ideally required including calculation of Fam in accordance with
the procedures of this Recommendation.
4.2 Intermodulation
In order to protect the DSC watch channels from the harmful effects of interference
caused by intermodulation products, a new program is ideally required to enable the
frequencies assigned for use on a shore-based transmitting station to be checked to
ensure that no intermodulation products are produced within the passbands of the DSC
watch receivers, down to at least the 9th order. Such software should account for the
offset spectrum occupied by SSB transmissions to be used.
462 Maritime Manual
RECOMMENDATION ITU-R M.1842-1
Characteristics of VHF radio systems and equipment for
the exchange of data and electronic mail in the maritime
mobile service RR Appendix 18 channels
(2008-2009)
The ITU Radiocommunication Assembly,
considering
a) that Resolution 342 (Rev.WRC-2000) of the World Radiocommunication
Conference invites ITU-R to finalize studies currently ongoing, inter alia:
– identify the future requirements of the maritime mobile service;
– identify suitable technical characteristics of the system or interoperable
systems;
– identify necessary modifications to the table of frequencies contained in
Appendix 18;
b) that IMO has stated that the maritime industry has a need for
radiocommunications for business and safety. At IMO the future need for
harmonization of systems using maritime VHF channels was considered, and ITU-R
has been informed of the possible future need for worldwide systems for the exchange
of data and electronic mail on maritime VHF channels,
recognizing
that in accordance with RR Appendix 18 channels used for VHF data shall not cause
harmful interference to and shall not claim protection from other stations operating in
accordance with RR Article 5. This includes SOLAS applications such as GMDSS on
channel 70 and AIS 1 and AIS 2,
recommends
1 that the characteristics for VHF data described in the Annexes to this
Recommendation should be considered as examples of such systems;
2 this Recommendation should be used as a guideline for future digital
technologies in the maritime mobile service VHF bands;
3 that new VHF data systems introduced should provide characteristics that are
compatible with the existing voice and data system, particularly the AIS.
Part C – Rec. ITU-R M.1842-1 463
Annex 1
VHF data system example 1
The following characteristics should be indicative of a VHF radio system for the
exchange of data and electronic mail in the maritime mobile service.
1 General characteristics
1.1 The class of emission should be 16K0F1DDN.
1.2 The necessary band should cater for the channels in RR Appendix 18
designated with footnote o), each with 25 kHz bandwidth.
1.3 The modulation may be either #/4 DQPSK at 28.8 kbit/s or #/8 D8-PSK at
43.2 kbit/s, depending on required station-station radio range and channel
signal fidelity.
1.4 The access method may be carrier sense time division multiple access
(CSTDMA).
1.5 The following area coverage techniques may be used:
– cellular channel reuse;
– time sharing transmission.
1.6 The following handover techniques may be utilized:
– uninterrupted handover (channel and base station);
– uninterrupted file transfer.
1.7 The equipment should be designed so that frequency changes between
assigned channels can be carried out in less than 100 ms.
1.8 Switching between reception and transmission should not take more than 2 ms.
1.9 The serial communication channels (SCC) on a single radio modem may be:
– Ethernet;
– RS232 (NMEA).
1.10 The radio equipment should meet the following norms:
– radio parameters: ETSI EN 300 113-1;
– EMC: ETSI EN 301 489-5.
464 Maritime Manual
2 Transmitters
2.1 The frequency tolerance for coast station transmitters should not exceed
5 parts in 106, and that for ship station transmitters should not exceed 10 parts
in 106.
2.2 Spurious emissions should be in accordance with the provisions of RR
Appendix 3.
2.3 The carrier power for coast station transmitters should not exceed 50 W.
2.4 The carrier power for ship station transmitters should not exceed 25 W.
2.5 The cabinet radiated power should not exceed 25 µW.
2.6 The adjacent channel power ratio (ACPR) should be at least 70 dB (see
Fig. 3).
3 Receivers
3.1 The receiver sensitivity for bit error rate (BER) 10–3 should be better
than –107 dBm.
3.2 The adjacent channel selectivity should be at least 70 dB.
3.3 The spurious response rejection ratio should be at least 70 dB.
3.4 The radio frequency intermodulation rejection ratio should be at least 70 dB.
3.5 The power of any conducted spurious emission at the antenna terminals should
not exceed 2.0 nW.
4 Sample emissions spectrum based on variations of ETSI TETRA
standard modulation
This proposal refers to the work of RTCM Special Committee 123 (RTCM SC123)
which evaluated the ETSI TETRA modulation schemes for use in RR Appendix 18.
Part C – Rec. ITU-R M.1842-1 465
FIGURE 1
36 kbit/s !/4-DQPSK and 54 kbit/s !/8-D8-PSK modulation spectra
RTCM SC123 test results for TETRA-TEDS modulation
Results
Figure 1 presents the spectra for TETRA and TEDS modulations, at their normal
36/54 kbit/s data rates, along with the IEC 61993-2 25 kHz mask for comparison. It is
apparent these modulations fail to meet the mask; their power exceeds the –25 dBm
limit at a 10 kHz offset from the carrier.
466 Maritime Manual
FIGURE 2
Family of spectrum plots for different data rates
RTCM test results for slightly reduced data rates to fit Appendix 18 emissions mask
Somewhat lower 32/48 kbit/s and 28.8/43.2 kbit/s data rate combinations were then
tested. Figure 2 overlays these results with those of Fig. 1. It is evident 32 kbit/s
#/4-DQPSK and 48 kbit/s #/8-D8-PSK modulations just barely fit or violate the mask
whereas 28.8 kbit/s #/4-DQPSK and 43.2 kbit/s #/8-D8-PSK modulations
comfortably fit the mask.
Part C – Rec. ITU-R M.1842-1 467
FIGURE 3
Adjacent channel power ratio (ACPR) performance
RTCM test results: 28.8 kbit/s !/4-DQPSK and 43.2 kbit/s !/8-D8-PSK modulation
468 Maritime Manual
5 Conclusions on emissions
Emissions spectrum requirements for RR Appendix 18 based on maritime IEC test
standards will allow both #/4 DQPSK at 28.8 kbit/s and #/8 D8-PSK at 43.2 kbit/s
modulation to be used.
6 System interoperability
6.1 Ship-to-shore
In the ship-to-shore direction interoperability is maintained by the internet service
provider (ISP) at the internet protocol (IP) level. Typically, a ship will enter an
electronic mail, with or without attachments, in the electronic mail system and then
click on the “send” button.
6.2 Shore-to-ship
In this system, there are no interoperability concerns on the part of the shore-side user.
The shore-based sender of an electronic mail to a ship can merely:
a) click on the “reply” button, or
b) address the message to [email protected] or [email protected].
The electronic mail will be delivered via whatever system the ship is using. If there is a
system failure, there will be an automatic re-route via an alternate system. These
automated decisions are based on the contents of an extensive database. Consequently,
the electronic mail may be delivered via HF or an alternate satellite-based system. If
there is an overall system failure, addressing problem or non-delivery for any reason,
the system support operators will be alerted and take corrective action. This ensures that
shore-based users need not be concerned about what system or network the ship is
using. They need only address the electronic mail and click on “send”.
6.3 Ship-to-ship
The VDL protocol should also provide for direct transmission between ships where
possible (within radio propagation range) in the simplex ship-ship mode. The duplex
ship-shore-ship mode should be used for extended range (beyond the ship-ship radio
propagation range).
6.4 Efficient use of the VHF data link (VDL)
System interoperability should be achieved for all transmission modes, ship-to-shore,
shore-to-ship, and ship-to-ship. Spectrum efficiency and data throughput should also be
considered. For example, application of the electronic mail internet protocol (IP) at the
network level and not on the VDL would result in an efficiency improvement of 3:1.
Part C – Rec. ITU-R M.1842-1 469
Annex 2
VHF data system example 2
Introduction
This Annex describes an existing narrowband VHF data system for the exchange of
data and electronic mail in the maritime mobile service. The system is currently in use,
operating from base stations ashore and on offshore installations.
1 General characteristics
1.1 The system is operating on nine duplex 25 kHz channels in the maritime VHF
band.
1.2 The class of emission is 16K0F1DDN.
1.3 The modulation is 4-level GMSK. Transmitted bit rate 21.1 kbit/s.
1.4 The access method is time division multiple access (TDMA).
1.5 The following area coverage techniques are used:
– cellular channel reuse;
– time sharing transmission.
1.6 The following handover techniques are utilized:
– uninterrupted handover (channel and base station);
– uninterrupted file transfer.
1.7 The equipment is designed so that frequency changes between assigned
channels can be carried out in less than 100 ms.
1.8 Emissions are vertically polarized at the source.
1.9 Switching between reception and transmission should not take more than 2 ms.
1.10 The serial communication channels (SCC) on a single radio modem should be:
– Ethernet;
– RS232 (NMEA);
– IEC 61162.
1.11 The radio equipment should meet the following norms:
– radio parameters: ETSI EN 300 113-1;
– EMC: ETSI EN 301 489-5 and IEC 60945.
470 Maritime Manual
2 Transmitters
2.1 The frequency tolerance for coast station transmitters should not exceed five
parts in 106, and that for ship station transmitters should not exceed ten parts in
106.
2.2 In order to prevent harmful interference to other users of the maritime VHF
band, spurious emissions should be in accordance with the provisions of RR
Appendix 3.
2.3 The carrier power for coast station transmitters should not exceed 50 W.
2.4 The carrier power for ship station transmitters should not exceed 25 W.
2.5 The cabinet radiated power should not exceed 25 µW.
2.6 Adjacent channel power ratio (ACPR) should be at least 70 dB.
3 Receivers
3.1 The receiver sensitivity for bit-error rate (BER) 10–3 should be better
than –107 dBm .
3.2 The adjacent channel selectivity should be at least 70 dB.
3.3 The spurious response rejection ratio should be at least 70 dB.
3.4 The radio frequency intermodulation rejection ratio should be at least 70 dB.
3.5 The power of any conducted spurious emission at the antenna terminals should
not exceed 2.0 nW.
4 Possibilities and advantages
4.1 Coverage and stability
The VHF band has very good qualities regarding range and stability. Typical
range from a land-based station is up to 70 NM.
4.2 IP – Ethernet
The common used Ethernet protocol that makes connection to local data
networks and other data services easy.
4.3 Fixed IP address at the radio on board the ship
This makes it possible to send data to the ship without anyone being needed to
activate the link. The ship may also have ten local IP addresses.
Part C – Rec. ITU-R M.1842-1 471
4.4 Always connected
There is no connection time. This makes the system very effective for real-
time applications, e.g. banking terminals.
4.5 Several services in parallel from one radio on the ship
The system is based on packets all the way. From one radio on the ship one
may carry out several different services at the same time. The system is
therefore frequency efficient.
4.6 Automatic reconnection after disruption
The system will automatically reconnect and continue the tasks again at the
right point. This happens both after short breaks as well as long breaks, e.g.
outside radio coverage area.
4.7 Integrated data router
The radio is delivered with an integrated router. It means that tasks may be
programmed directly into the radio and may be carried out without the use of a
PC. For example, the fishing boat positioning and moving report system is
programmed into the radio/router. In addition, the router has very large
capacity to carry out several tasks, among other things compression and
decompression of electronic mail, web applications and weather maps.
4.8 Several inputs to the radio
Ethernet cable may be plugged directly into the radio or the router, enabling
easy establishment of a local net on board the ship. Other digital or analogue
inputs may be used for GNSS, measuring instruments, etc.
4.9 Connection to local WLAN
The system may be combined with local wireless networks on board the ship.
4.10 External communication carriers
The system may be delivered with possibilities for seamless connection to
external networks, e.g. wireless LANs in harbour areas or to satellite
communication.
5 Applications
Some current and possible future applications of VHF data are listed below:
– safe SeaNet reporting (ISPS);
472 Maritime Manual
– fishery catch reporting;
– fishing boat position and movement reporting;
– weather maps;
– general electronic mail;
– messages to the ship’s agent, the pilot or harbour authorities;
– banking terminals, especially on passenger ships;
– safety-related information;
– telemetry information;
– updating of electronic maps.
6 System interoperability
6.1 Ship-to-shore
In the ship-to-shore direction interoperability is maintained by the Internet
service provider (ISP) at the internet protocol (IP) level. Typically, a ship will
enter an electronic mail, with or without attachments, in the electronic mail
system and then click on the “send” button.
6.2 Shore-to-ship
In this system, there are no interoperability concerns on the part of the shore-
side user. The shore-based sender of an electronic mail to a ship can merely:
a) click on the “reply” button, or
b) address the message to [email protected] or [email protected].
The electronic mail will be delivered via whatever system the ship is using. If
there is a system failure, there will be an automatic re-route via an alternate
system. These automated decisions are based on the contents of an extensive
database. Consequently, the electronic mail may be delivered via HF or an
alternate satellite-based system. If there is an overall system failure, addressing
problem or non-delivery for any reason, the system support operators will be
alerted and take corrective action. This ensures that shore- based users need
not be concerned about what system or network the ship is using. They need
only address the electronic mail and click on “send”.
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PART D
Extracts from the International
Telecommunication Regulations
(Melbourne, 1988)
Note by the Secretariat: In preparing the extracts from the International
Telecommunication Regulations (Melbourne, 1988), the Secretariat made editorial
changes, where appropriate, to reflect the ITU structural changes (world administrative
radio conference to world radiocommunication conference, CCIR to ITU-R, CCITT to
ITU-T, IFRB to the Radiocommunication Bureau, Administrative Council to Council,
etc.)
In addition, the term “Member(s)” has been replaced by the term “Member State(s)‡” to
correspond with the terminology employed currently within the ITU. The symbol “‡”
indicates that this replacement was made by the Secretariat.
Part D – ITR 475
INTERNATIONAL TELECOMMUNICATION REGULATIONS
Article 1
Purpose and Scope of the Regulations
2 1.1 a) These Regulations establish general principles which relate to the provision and
operation of international telecommunication services offered to the public as well as to
the underlying international telecommunication transport means used to provide such
services. They also set rules applicable to administrations*.
3 b) These Regulations recognize in Article 9 the right of Member States‡ to allow
special arrangements.
4 1.2 In these Regulations, “the public” is used in the sense of the population, including
governmental and legal bodies.
5 1.3 These Regulations are established with a view to facilitating global interconnection
and interoperability of telecommunication facilities and to promoting the harmonious
development and efficient operation of technical facilities, as well as the efficiency,
usefulness and availability to the public of international telecommunication services.
6 1.4 References to ITU-T Recommendations and Instructions in these Regulations are
not to be taken as giving to those Recommendations and Instructions the same legal status
as the Regulations.
7 1.5 Within the framework of the present Regulations, the provision and operation of
international telecommunication services in each relation is pursuant to mutual agreement
between administrations*.
8 1.6 In implementing the principles of these Regulations, administrations* should
comply with, to the greatest extent practicable, the relevant ITU-T Recommendations,
including any Instructions forming part of or derived from these Recommendations.
9 1.7 a) These Regulations recognize the right of any Member State‡, subject to national
law and should it decide to do so, to require that administrations* and private
operating agencies, which operate in its territory and provide an international
telecommunication service to the public, be authorized by that Member State‡.
10 b) The Member State‡ concerned shall, as appropriate, encourage the application
of relevant ITU-T Recommendations by such service providers.
11 c) The Member States‡, where appropriate, shall cooperate in implementing the
International Telecommunication Regulations (for interpretation, also see
Resolution No. 2).
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* or recognized private operating agency(ies)
476 Maritime Manual
12 1.8 The Regulations shall apply, regardless of the means of transmission used, so far as
the Radio Regulations do not provide otherwise.
Article 2
Definitions
13 For the purpose of these Regulations, the following definitions shall apply. These
terms and definitions do not, however, necessarily apply for other purposes.
21 2.6 International route: Technical facilities and installations located in different
countries and used for telecommunication traffic between two international
telecommunication terminal exchanges or offices.
22 2.7 Relation: Exchange of traffic between two terminal countries, always referring to a
specific service if there is between their administrations*:
23 a) a means for the exchange of traffic in that specific service:
– over direct circuits (direct relation), or
– via a point of transit in a third country (indirect relation), and
24 b) normally, the settlement of accounts.
25 2.8 Accounting rate: The rate agreed between administrations* in a given relation that
is used for the establishment of international accounts.
26 2.9 Collection charge: The charge established and collected by an administration*
from its customers for the use of an international telecommunication service.
27 2.10 Instructions: A collection of provisions drawn from one or more ITU-T
Recommendations dealing with practical operational procedures for the handling of
telecommunication traffic (e.g., acceptance, transmission, accounting).
Article 3
International Network
28 3.1 Member States‡ shall ensure that administrations* cooperate in the establishment,
operation and maintenance of the international network to provide a satisfactory quality of
service.
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* or recognized private operating agency(ies)
Part D – ITR 477
29 3.2 Administrations* shall endeavour to provide sufficient telecommunication facilities
to meet the requirements of and demand for international telecommunication services.
30 3.3 Administrations* shall determine by mutual agreement which international routes
are to be used. Pending agreement and provided that there is no direct route existing
between the terminal administrations* concerned, the origin administration* has the choice
to determine the routing of its outgoing telecommunication traffic, taking into account the
interests of the relevant transit and destination administrations*.
31 3.4 Subject to national law, any user, by having access to the international network
established by an administration*, has the right to send traffic. A satisfactory quality of
service should be maintained to the greatest extent practicable, corresponding to relevant
ITU-T Recommendations.
Article 4
International Telecommunication Services
32 4.1 Member States‡ shall promote the implementation of international tele-
communication services and shall endeavour to make such services generally available to
the public in their national network(s).
33 4.2 Member States‡ shall ensure that administrations* cooperate within the framework
of these Regulations to provide by mutual agreement, a wide range of international
telecommunication services which should conform, to the greatest extent practicable, to
the relevant ITU-T Recommendations.
34 4.3 Subject to national law, Member States‡ shall endeavour to ensure that
administrations* provide and maintain, to the greatest extent practicable, a minimum
quality of service corresponding to the relevant ITU-T Recommendations with respect to:
35 a) access to the international network by users using terminals which are
permitted to be connected to the network and which do not cause harm to
technical facilities and personnel;
36 b) international telecommunication facilities and services available to customers
for their dedicated use;
37 c) at least a form of telecommunication which is reasonably accessible to the
public, including those who may not be subscribers to a specific
telecommunication service; and
38 d) a capability for interworking between different services, as appropriate, to
facilitate international communications.
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* or recognized private operating agency(ies)
478 Maritime Manual
Article 5
Safety of Life and Priority of Telecommunications
39 5.1 Safety of life telecommunications, such as distress telecommunications, shall be
entitled to transmission as of right and shall, where technically practicable, have absolute
priority over all other telecommunications, in accordance with the relevant Articles of the
Convention and taking due account of relevant ITU-T Recommendations.
40 5.2 Government telecommunications, including telecommunications relative to the
application of certain provisions of the United Nations Charter, shall, where technically
practicable, enjoy priority over telecommunications other than those referred to in No. 39,
in accordance with the relevant provisions of the Convention and taking due account of
relevant ITU-T Recommendations.
41 5.3 The provisions governing the priority enjoyed by all other telecommunications are
contained in the relevant ITU-T Recommendations.
Article 6
Charging and Accounting
42 6.1 Collection charges
43 6.1.1 Each administration* shall, subject to applicable national law, establish the charges
to be collected from its customers. The level of the charges is a national matter; however,
in establishing these charges, administrations* should try to avoid too great a dissymmetry
between the charges applicable in each direction of the same relation.
44 6.1.2 The charge levied by an administration* on customers for a particular
communication should in principle be the same in a given relation, regardless of the route
chosen by that administration*.
45 6.1.3 Where, in accordance with the national law of a country, a fiscal tax is levied on
collection charges for international telecommunication services, this tax shall normally be
collected only in respect of international services billed to customers in that country,
unless other arrangements are made to meet special circumstances.
46 6.2 Accounting rates
47 6.2.1 For each applicable service in a given relation, administrations* shall by mutual
agreement establish and revise accounting rates to be applied between them, in
accordance with the provisions of Appendix 1 and taking into account relevant ITU-T
Recommendations and relevant cost trends.
_______________
* or recognized private operating agency(ies)
Part D – ITR 479
51 6.4 Establishment of accounts and settlement of balances of account
52 6.4.1 Unless otherwise agreed, administrations* shall follow the relevant provisions as
set out in Appendices 1 and 2.
Article 7
Suspension of Services
55 7.1 If a Member State‡ exercises its right in accordance with the Convention to
suspend international telecommunication services partially or totally, that Member State‡
shall immediately notify the Secretary-General of the suspension and of the subsequent
return to normal conditions by the most appropriate means of communication.
56 7.2 The Secretary-General shall immediately bring such information to the attention of
all other Member States‡, using the most appropriate means of communication.
Article 9
Special Arrangements
58 9.1 a) Pursuant to Article 31 of the International Telecommunication Convention
(Nairobi, 1982), special arrangements may be entered into on telecommunication matters
which do not concern Member States‡ in general. Subject to national laws, Member
States‡ may allow administrations* or other organizations or persons to enter into such
special mutual arrangements with Member States‡, administrations* or other organizations
or persons that are so allowed in another country for the establishment, operation, and use
of special telecommunication networks, systems and services, in order to meet specialized
international telecommunication needs within and/or between the territories of the
Member States‡ concerned, and including, as necessary, those financial, technical, or
operating conditions to be observed.
59 b) Any such special arrangements should avoid technical harm to the operation of
the telecommunication facilities of third countries.
60 9.2 Member States‡ should, where appropriate, encourage the parties to any special
arrangements that are made pursuant to No. 58 to take into account relevant provisions of
ITU-T Recommendations.
_______________
* or recognized private operating agency(ies)
480 Maritime Manual
Article 10
Final Provisions
61 10.1 These Regulations, of which Appendices 1, 2 and 3 form integral parts, shall enter
into force on 1 July 1990 at 0001 hours UTC.
62 10.2 On the date specified in No. 61, the Telegraph Regulations (Geneva, 1973) and the
Telephone Regulations (Geneva, 1973) shall be replaced by these International
Telecommunication Regulations (Melbourne, 1988) pursuant to the International
Telecommunication Convention.
63 10.3 If a Member State‡ makes reservations with regard to the application of one or
more of the provisions of these Regulations, other Member States‡ and their
administrations* shall be free to disregard the said provision or provisions in their
relations with the Member State‡ which has made such reservations and its
administrations*.
_______________
* or recognized private operating agency(ies)
Part D – ITR 481
APPENDIX 1
General Provisions Concerning Accounting ITR
1. Accounting rates
1.1 For each applicable service in a given relation, administrations* shall by mutual
agreement establish and revise accounting rates to be applied between them, taking into account
the Recommendations of the ITU-T and trends in the cost of providing the specific
telecommunication service, and shall divide such rates into terminal shares payable to the
administrations* of terminal countries, and where appropriate, into transit shares payable to the
administrations* of transit countries.
1.2 Alternatively, in traffic relations where ITU-T cost studies can be used as a basis, the
accounting rate may be determined in accordance with the following method:
a) administrations* shall establish and revise their terminal and transit shares taking into
account the Recommendations of the ITU-T;
b) the accounting rate shall be the sum of the terminal shares and any transit shares.
1.3 When one or more administrations* acquire, either by flat rate remuneration or other
arrangements, the right to utilize a part of the circuit and/or installations of another
administration*, the former have the right to establish their share as mentioned in 1.1 and 1.2
above, for this part of the relation.
1.4 In cases where one or more routes have been established by agreement between
administrations* and where traffic is diverted unilaterally by the administration* of origin to a
route which has not been agreed with the administration* of destination, the terminal shares
payable to the administration* of destination shall be the same as would have been due to it had
the traffic been routed over the agreed primary route and the transit costs are borne by the
administration* of origin, unless the administration* of destination is prepared to agree to a
different share.
1.5 In cases where the traffic is routed via a transit point without authorization and/or
agreement to the transit share, the transit administration* has the right to set the level of the
transit share to be included in the international accounts.
1.6 Where an administration* has a duty or fiscal tax levied on its accounting rate shares or
other remunerations, it shall not in turn impose any such duty or fiscal tax on other
administrations*.
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* or recognized private operating agency(ies)
482 Maritime Manual
2. Establishment of accounts
2.1 Unless otherwise agreed, the administrations* responsible for collecting the charges shall
establish a monthly account showing all the amounts due and send it to the administrations*
concerned.
2.2 The accounts shall be sent as promptly as possible and, except in cases of force majeure,
before the end of the third month following that to which they relate.
2.3 In principle an account shall be considered as accepted without the need for specific
notification of acceptance to the administration* which sent it.
2.4 However, any administration* has the right to question the contents of an account for a
period of two calendar months after the receipt of the account, but only to the extent necessary to
bring any differences within mutually agreed limits.
2.5 In relations where there are no special agreements, a quarterly settlement statement
showing the balances of the monthly accounts for the period to which it relates shall be prepared
as soon as possible by the creditor administration* and shall be sent in duplicate to the debtor
administration*, which, after verification, shall return one of the copies endorsed with its
acceptance.
2.6 In indirect relations where a transit administration* acts as an accounting intermediary
between two terminal points, it shall include accounting data for transit traffic in the relevant
outgoing traffic account to administrations* beyond it in the routing sequence as soon as possible
after receiving that data from the originating administration*.
3. Settlement of balances of accounts
3.1 Choice of the currency of payment
3.1.1 The payment of balances of international telecommunication accounts shall be made in
the currency selected by the creditor after consultation with the debtor. In the event of
disagreement, the choice of the creditor shall prevail in all cases subject to the provisions in
3.1.2 below. If the creditor does not specify a currency, the choice shall rest with the debtor.
3.1.2 If a creditor selects a currency with a value fixed unilaterally or a currency the equivalent
value of which is to be determined by its relationship to a currency with a value also fixed
unilaterally, the use of the selected currency must be acceptable to the debtor.
3.2 Determination of the amount of payment
3.2.1 The amount of the payment in the selected currency, as determined below, shall be
equivalent in value to the balance of the account.
_______________
* or recognized private operating agency(ies)
Part D – ITR 483
3.2.2 If the balance of the account is expressed in the monetary unit of the IMF, the amount of
the selected currency shall be determined by the relationship in effect on the day before
payment, or by the latest relationship published by the IMF, between the monetary unit of the
IMF and the selected currency.
3.2.3 However, if the relationship of the monetary unit of the IMF to the selected currency has
not been published, the amount of the balance of account shall, at a first stage, be converted into
a currency for which a relationship has been published by the IMF, using the relationship in
effect on the day before payment or the latest published relationship. The amount thus obtained
shall, at a second stage, be converted into the equivalent value of the selected currency, using the
closing rate in effect on the day prior to payment or the most recent rate quoted on the official or
generally accepted foreign exchange market of the main financial centre of the debtor country.
3.2.4 If the balance of the account is expressed in gold francs, the amount shall, in the absence
of special arrangements, be converted into the monetary unit of the IMF in accordance with the
provisions of section 6.3 of the Regulations. The amount of payment shall then be determined in
compliance with the provisions of 3.2.2. above.
3.2.5 If, in accordance with a special arrangement, the balance of the account is expressed
neither in the monetary unit of the IMF nor in gold francs, the payment shall also be the subject
of this special arrangement and:
a) if the selected currency is the same as the currency of the balance of account, the
amount of the selected currency shall be the amount of the balance of account;
b) if the selected currency for payment is different from the currency in which the
balance is expressed, the amount shall be determined by converting the balance of
account to its equivalent value in the selected currency in accordance with the
provisions of 3.2.3 above.
3.3 Payment of balances
3.3.1 Payment of balances of account shall be effected as promptly as possible, but in no case
later than two calendar months after the day on which the settlement statement is despatched by
the creditor administration*. Beyond this period, the creditor administration* may, subject to
prior notification in the form of a final demand for payment, and unless otherwise agreed, charge
interest at a rate of up to 6% per annum, reckoned from the day following the date of expiry of
the said period.
3.3.2 The payment due on a settlement statement shall not be delayed pending settlement of a
query on that account. Adjustments which are later agreed shall be included in a subsequent
account.
3.3.3 On the date of payment, the debtor shall transmit the amount of the selected currency as
computed above by a bank cheque, transfer or any other means acceptable to the debtor and the
creditor. If the creditor expresses no preference, the choice shall fall to the debtor.
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* or recognized private operating agency(ies)
484 Maritime Manual
3.3.4 The payment charges imposed in the debtor country (taxes, clearing charges,
commissions, etc.) shall be borne by the debtor. Any such charges imposed in the creditor
country, including payment charges imposed by intermediate banks in third countries, shall be
borne by the creditor.
3.4 Additional provisions
3.4.1 Provided the periods of payment are observed, administrations* may by mutual agreement
settle their balances of various kinds by offsetting:
– credits and debits in their relations with other administrations*; and/or
– debts arising from postal services, if appropriate.
3.4.2 If, between the time the remittance (bank transfer, cheques, etc.) is effected and the time
the creditor is in receipt of that remittance (account credited, cheque encashed, etc.), a variation
occurs in the equivalent value of the selected currency calculated as indicated in paragraph 3.2,
and if the difference resulting from such variations exceeds 5% of the amount due as calculated
following such variations, the total difference shall be shared equally between debtor and
creditor.
3.4.3 If there should be a radical change in the international monetary system which
invalidates or makes inappropriate one or more of the foregoing paragraphs, administrations* are
free to adopt, by mutual agreement, a different monetary basis and/or different procedures for
the settlement of balances of accounts, pending a revision of the above provisions.
_______________
* or recognized private operating agency(ies)
Part D – ITR 485
APPENDIX 2
Additional Provisions Relating to
Maritime Telecommunications ITR
1. General
The provisions contained in Article 6 and Appendix 1, taking into account the relevant
ITU-T Recommendations, shall also apply to maritime telecommunications in so far as the
following provisions do not provide otherwise.
2. Accounting authority
2.1 Charges for maritime telecommunications in the maritime mobile service and the
maritime mobile-satellite service shall in principle, and subject to national law and practice, be
collected from the maritime mobile station licensee:
a) by the administration that has issued the licence; or
b) by a recognized private operating agency; or
c) by any other entity or entities designated for this purpose by the administration
referred to in a) above.
2.2 The administration or the recognized private operating agency or the designated entity or
entities listed in paragraph 2.1 are referred to in this Appendix as the “accounting authority”.
2.3 References to administration* contained in Article 6 and Appendix 1 shall be read as
“accounting authority” when applying the provisions of Article 6 and Appendix 1 to maritime
telecommunications.
2.4 Member States‡ shall designate their accounting authority or authorities for the purposes
of implementing this Appendix and notify their names, identification codes and addresses to the
Secretary-General for inclusion in the List of Ship Stations; the number of such names and
addresses shall be limited taking into account the relevant ITU-T Recommendations.
3. Establishment of accounts
3.1 In principle, an account shall be considered as accepted without the need for specific
notification of acceptance to the accounting authority that sent it.
3.2 However, any accounting authority has the right to question the contents of an account for
a period of six calendar months after dispatch of the account.
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* or recognized private operating agency(ies)
486 Maritime Manual
4. Settlement of balances of account
4.1 All international maritime telecommunication accounts shall be paid by the accounting
authority without delay and in any case within six calendar months after dispatch of the account,
except where the settlement of accounts is undertaken in accordance with paragraph 4.3 below.
4.2 If international maritime telecommunication accounts remain unpaid after six calendar
months, the administration that has licensed the mobile station shall, on request, take all possible
steps, within the limits of applicable national law, to ensure settlement of the accounts from the
licensee.
4.3 If the period between the date of dispatch and receipt exceeds one month, the receiving
accounting authority should at once notify the originating accounting authority that queries and
payments may be delayed. The delay shall, however, not exceed three calendar months in
respect of payment, or five calendar months in respect of queries, both periods commencing
from the date of receipt of the account.
4.4 The debtor accounting authority may refuse the settlement and adjustment of accounts
presented more than eighteen calendar months after the date of the traffic to which the accounts
relate.
_______________
PART E
Extracts from the ITU-T Recommendations∗
_______________
∗ See Note by the Secretariat, Part D.
Part E 489
Notes
1. In these Recommendations, the expression Administration is used for
conciseness to indicate both a telecommunication administration and a recognized
operating agency.
2. Should there be any conflict regarding the time scale in the ITU-T Recommen-
dation D.90 and those stated in Appendix 2 of the International Telecommunication
Regulations then the latter would prevail.
4. For the purpose of the ITU-T Recommendation F.110, the references
commencing with the letters J, K, L and M concern provisions in Divisions J, K, L
and M respectively of ITU-T Recommendation D.90 entitled Charging, billing,
international accounting and settlement in the Maritime Mobile Service.
5. For the purpose of the ITU-T Recommendation F.110 the term Maritime
Mobile Service should be understood to embrace the Maritime Mobile-Satellite Service
as well as the MF, HF, VHF and UHF radio media, unless specifically stated otherwise.
6. Throughout the ITU-T Recommendation F.110 the term Administration means
that recognized private operating agency/agencies are included. However, where this
term is used in respect of notification by Administrations to the General Secretariat of
the ITU, this applies only to recognized private operating agencies that have been
authorized by Administrations to carry out such notification.
7. For the purpose of the ITU-T Recommendation F.110, the terms mobile station
and land station should be considered as analogous to ship station and coast station
respectively used in the Radio Regulations.
Part E – ITU-T Rec. D.90 491
ITU-T Recommendation D.90
CHARGING, BILLING, INTERNATIONAL ACCOUNTING AND
SETTLEMENT IN THE MARITIME MOBILE SERVICE
(Revised in 1995)
1 Introduction
1.1 This Recommendation sets out the principles for charging, billing, international
accounting and settlement for the maritime mobile service. It covers:
– the procedures for the rendering of a bill by a service provider in respect of the
collection charges payable by a maritime mobile station;
– the payment procedures related to the bill;
– the inter-Administration/ROA (service provider) international accounting
procedures when maritime mobile traffic involves a terrestrial international call
and, where applicable, the use of a land station in a country other than the one
where the call originates/terminates.
1.2 The following provides an explanation of terminology used in this Recommendation.
1.2.1 Maritime mobile service – The term is used in this Recommendation to cover the
Maritime Mobile Satellite Service as well as the MF, HF and VHF radio media, unless
specifically stated otherwise.
1.2.2 Service provider – The Administration/ROA who provides the communication service
to/from maritime mobile stations.
1.2.3 Land Station (LS) – This term is used to cover both fixed Land Earth Station and
Coast Station.
1.2.4 Land Station Operator (LSO) – An entity which operates a Land Station in the
Maritime Mobile Service. This can be an Administration/ROA or other entity(ies) designated by
the Administration to operate the Land Station.
1.2.5 Maritime mobile station – This term is used to include a maritime mobile satellite
station, and in the context of billing refers to the Licensee, equating to the use of the term
customer in the terrestrial service. It equates to Ship Station used in die Radio Regulations.
1.2.6 Maritime bill – The bill issued by the service provider in respect of collection charges
for maritime mobile traffic originated by a maritime mobile station.
1.2.7 Land line charge – The charge relating to the transmission over the terrestrial public
switched telecommunications network.
1.2.8 Land station charge – The charge relating to the use of facilities provided by the land
station, which will include the space segment costs in the maritime mobile satellite case and
which may be presented by the LSO in its component parts.
1.2.9 Accounting Authority/Accounting Authority Identification Code – (See annex A.)
492 Maritime Manual
3 Collection charges
3.1 General principles
See also Annex E – Case studies
3.1.1 The charge structure and level is a national matter.
3.1.2 The collection charges may take account of the following elements:
a) the national/international (if applicable) link = the landline;
b) the land station;
c) the space segment (if applicable);
d) any special services or facilities.
3.1.3 For communication between a maritime mobile station and a country other than that of
the land station (cases 3, 4):
3.1.3.1 The international land line charges shall normally be the collection charges applicable
in the international relation concerned for the services used.
3.1.3.2 Service providers may choose to establish a combined collection charge covering both
the landline and the land station.
3.1.4 Communications between maritime mobile stations:
3.1.4.1 When a single land station is used as an intermediary between maritime mobile
stations, two maritime land station charges are collected. If the land station charge applicable to
traffic with the origin maritime mobile station is different from that applicable to traffic with the
destination maritime mobile station, the sum of these two charges is collected.
3.1.4.2 When it is necessary to use two land stations in different countries as intermediaries
between two maritime mobile stations (case 6), the landline charge for the section between the
two land stations (normally the collection charge applicable in the international relation
concerned for the service used) is collected in addition to the two land station charges.
3.1.4.3 When it is necessary to use two land stations in the same country as intermediary
between two maritime mobile stations a national landline charge between the two land stations is
collected in addition to the two land station charges.
3.1.5 If authorised to do so by its licensing Administration, a maritime mobile station may
collect on board a fee from users, for the use of facilities provided, in addition to the service
provider's collection charges. Such a fee will be retained by the maritime mobile station. The
licensing Administration may set an upper limit to these fees.
3.2 Publication of collection charges by the ITU
3.2.1 The landline and land station charges shall be notified by the service provider to the
Radiocommunication Bureau in the unit of the IMF, currently the SDR (Special Drawing Right),
or in Gold Francs which is the equivalent to 1/3.061 SDR (1 SDR = 3.061 GFcs).
Part E – ITU-T Rec. D.90 493
3.2.2 The landline and land station charges notified to the Radiocommunication Bureau will
be published in the List of Coast Stations.
3.2.3 For countries that have not introduced banded collection charges for international
services, only a limited number of charges, for routes in frequent use, will be published. In such
cases, the Radiocommunication Bureau will need to be informed which charges should be
published.
3.2.4 Maritime mobile stations must be aware of the collection charges. They are
authorized, where necessary, to obtain such information directly from land stations. Charges
furnished by land stations should be expressed either in SDRs or in Gold Francs (see 3.2.1
above).
3.3 Changes to collection charges
3.3.1 New or modified collection charges shall not come into effect for international traffic
for countries other than the one which establishes the charges until the first day of the month
following expiry of the period specified below. The period will be counted from the day after the
publication date of the ITU Operational Bulletin which contains this notification. Service
providers providing information for publication in the Operational Bulletin should observe the
deadlines indicated in the Bulletin in forwarding this information to the Radiocommunication
Bureau.
3.3.2 The period to be taken into account is as follows:
a) for traffic from maritime mobile station to land: I month and 15 days;
b) for traffic from land to maritime mobile station: 15 days, except for changes to
bring charges into line with those on competing routes where the period is
10 days.
3.4 Special charging arrangements
3.4.1 Communications of immediate general interest ( including safety and distress)
No charge is raised, against the maritime mobile station, for transmission in the maritime mobile
service provided that the communications are :
a) distress calls/messages or replies to such calls/messages;
b) messages originating in maritime mobile stations requiring shore rescue authority
support, e.g. man overboard, oil pollution or piracy attack;
c) messages originating in maritime mobile stations notifying the presence of
dangers to navigation (e.g. icebergs, derelicts, mines) or announcing cyclones,
storms or fog;
d) messages originating in maritime mobile stations notifying sudden changes in the
position of buoys, the working of lighthouses, devices connected with buoyage
etc.; or
e) messages originating in martime mobile stations notifying unexpected
phenomena threatening air navigation or the sudden occurrence of obstacles at
airports or special landing/berthing places at sea.
494 Maritime Manual
Any land station and landline charges for Safety and Distress communications will be billed to
the appropriate shore authority.
3.4.2 Communications relating to medical advice
No charge is raised against the originating maritime mobile station for communications using
the maritime mobile service which relate to medical advice provided that:
a) they are exchanged directly between maritime mobile stations and either Land
Stations shown in the List of Radiodetermination and Special Service Stations as
providing such a service, or Land Earth Stations which offer the service; and
b) they are addressed in accordance with the conditions published in the above List,
or as specificied by the satellite service operator.
Any land station and landline charges for medical advice communications will be billed to the
appropriate shore authority.
3.4.3 Meteorological communications
Charges for meteorological communications are a national matter.
3.4.4 Communications relating to persons protected in time of war
Radio telegrams concerning persons protected in time of war by the Geneva Convention of
12 August 1949 (RCT) will be accepted in accordance with Recommendation F.1, and will be
charged in accordance with Recommendation D.40.
3.4.5 Service communications in the maritime mobile service
Service telegrams or service telexes relating to the maritime mobile service should be treated in
accordance with Recommendation D.192.
3.5 Service specific charging principles
3.5.1 Radiotelegrams (see Recommendation F.110)
3.5.1.1 The land station charge is established on the basis of a word charge – see
Recommendation F.1.
3.5.1.2 No additional charge shall be made when acknowledgment of receipt of a
radiotelegram is made through another maritime mobile station or land station by service advice,
or when an intermediate maritime mobile station assists in the forwarding of a radiotelegram.
3.5.2 Radiomaritime letters (see Recommendation F.110)
3.5.2.1 Except as otherwise provided below, radiomaritime letters may be accepted, taking
into account ITU-T Recommendations relating to letter telegrams, if the telegram service is used
to convey radiomaritime letters.
3.5.2.2 The total charge shall include the postal charge (by ordinary letter or airmail letter)
due for delivery in the land station country.
Part E – ITU-T Rec. D.90 495
3.5.2.3 An additional charge may be collected where delivery is to be made to a country other
than that of the land station.
3.5.2.4 The following charges are added where applicable:
a) charges due for special services;
b) the landline charge when transmission on the land section is exceptionally by
telegraph.
3.5.3 Radiotelephone and radiotelex calls (see Recommendation F.110)
3.5.3.1 If no uniform charges apply in respect of the land stations of a country, different land
station charges shall be fixed for the MF, HF and VHF bands and for the maritime mobile
satellite service.
3.5.3.2 If, due to the lack of technical facilities, no extra charges apart from the normal
international landline charges can be levied by the origin Service Providers, no land station
charges will be collected for international automatic VHF radiotelephone calls in the to-maritime
mobile station direction, if so decided by the land station Service Providers. The List of Coast
Stations [1] shall indicate which Service Providers accept such calls without levying land station
charges.
3.5.3.3 When handled through a land station, the chargeable duration of a manual or single-
operator call will be fixed at the end of the call by the land station; if two land stations are
participating in the handling of the call, the record of the land station that accepted the call from
the originating maritime mobile station will prevail.
3.5.4 Radiotelexograms (see Recommendation F.110)
3.5.4.1 The charge for the landline element shall be that applicable to a telex call.
3.5.4.2 The charge for the landstation element shall be that applicable to a radiotelegram or
converted into chargeable duration units.
4 Maritime billing
4.1 Billing responsibilities
4.1.1 Collection charges for calls from shore to maritime mobile stations (cases 2, 4) will be
billed by the service provider to the calling customer in the normal customer billing process and
are not the subject of this subclause.
4.1.2 Collection charges for communications from maritime mobile stations to shore (cases
1, 3, 5 & 6) shall in principle and subject to national law and practice, be billed by the service
provider to:
a) An accounting authority or other third party agreed between the service provider
and the maritime mobile station;
b) the maritime mobile station; or
c) a credit/charge card company designated by the service provider.
496 Maritime Manual
NOTE – In cases b) and c) above the accounting authority of the maritime mobile station is not responsible for payment of the bills for communications originating from the maritime mobile station.
For cases b) and c) above, 4.2.2, 4.3.2., 4.4, 4.5, 4.6 and 4.7 do not apply, as the billing arrangements are the subject of agreement between the service provider and the maritime mobile station or the credit/charge card company.
4.1.3 The registration, responsibilities and identification of accounting authorities are
described in Annex A.
4.2 Billing processes and associated timescales
4.2.1 The processes involved in the billing of maritime mobile stations are described in 4.4,
4.5, and 4.7 below. The timescales associated with the various processes are summarized in
Annex D and represent the recommended maximum timescales. Variations to the timescales and
processes may be agreed between the service provider and the billed party (as defined in 4.1.2)
as part of their commercial arrangements.
4.2.2 In some instances, the International Telecommunications Regulations (ITR -
Appendix 2) provide for a longer maximum timescale than that recommended in this
Recommendation. The ITR timescales will be regarded as applicable in exceptional cases, for
example, where delays in rendering the bill to the correct accounting authority are encountered.
The timescales contained in this Recommendation shall be regarded as the normal maximum
timescales to be followed.
4.3 Billing procedures
4.3.1 The bills for communications originating in martime mobile stations should be based
on the following data gathered at the Land Station:
a) the maritime mobile station name, the maritime mobile station identification
and/or call sign;
b) the accounting authority identification code when required by the service
provider;
c) the credit/charge card details if applicable;
d) the number or identification of the addressee, including, for example, country
code and area codes;
e) the chargeable units;
f) date communication commenced, and time if appropriate;
g) traffic category;
h) type of call (automatic, operator assisted, collect, etc.);
i) special services/facilities used.
4.3.2 In the case of communications originating in maritime mobile stations, the service
provider shall bill, in accordance with the collection charges notified to the ITU in SDRs or
Gold Francs (see 3.2):
a) the land station charges;
Part E – ITU-T Rec. D.90 497
b) the landline charges;
c) any charges for special services or facilities;
d) where appropriate, postal charges on radiomaritime letters.
4.4 Preparation and despatch of bills
4.4.1 Bills are prepared monthly by the service provider and despatched to the accounting
authority responsible for the maritime mobile station, unless other arrangements have been
agreed between the service provider and the maritime mobile station.
4.4.2 Bills should be despatched as promptly as possible and by the most expeditious means
practicable but in any case before the end of the second month following that to which they
relate. (See Note 1.)
4.4.3 The bill will consist of two parts: a summary statement and a detailed communications
statement. This shall contain as a minimum the information identified in the specimen formats
shown in Annexes B and C. Both statements should be identified by the same unique bill
number and show the same date. In the communication statement, the calls shall be entered
individually with all necessary particulars for a given month. A separate statement for each
maritime mobile station should be established. The total charges for each maritime mobile
station should be included in the summary statement.
4.4.4 In the case of single-operator service, if bilaterally agreed between the service
providers concerned, the land station operator may despatch a bill directly to the booking caller
(see case 4).
4.4.5 In the case of collect calls to a maritime mobile station in the international maritime
mobile service, where permitted by the service provider, the total amount of the charges shall be
collected from the maritime mobile station.
4.5 Acceptance/queries/rejection
4.5.1 In principle, a bill shall be considered as accepted without the need for specific
notification of acceptance to the service provider that sent it.
4.5.2 The accounting authority should notify the billing service provider of any preliminary
rejections immediately upon receipt of a bill, for example if maritime mobile stations included in
the bill are not or no longer their responsibility.
4.5.3 However, any accounting authority shall have the right to question the contents of a
bill for a period of four months after its dispatch even if the bill has been paid. Any adjustments
which are later agreed shall he included in a subsequent bill.
4.6 Payment of bills
4.6.1 All bills shall be paid by the accounting authority without delay and in any event
within three months of receipt by the accounting authority or within four months of dispatch
whichever is the shorter period. The unique bill numbers and the traffic period(s) covered by the
498 Maritime Manual
payment should be quoted at the time of payment. The exception is where the provisions of 4.6.3
below apply. (See Note 1.)
4.6.2 If a bill remains unpaid after four months from dispatch, the Administration that has
licensed the maritime mobile station shall on request, take all possible steps within the limits of
applicable national law to ensure payment of the bill, provided that notification of late receipt
has not been advised as described in 4.6.3 below.
4.6.3 If the period between the date of dispatch of the bill and receipt exceeds twenty-one
days, the receiving accounting authority should at once notify the originating service provider
that queries and payment may be delayed. However, the delay shall not exceed three months
from date of receipt of the bill in respect of payment and in respect of queries even if the bill has
been paid.
4.6.4 The debtor accounting authority may refuse to pay or adjust bills rendered more than
fifteen months after the date of the traffic to which the bills relate. (See Note 2.)
4.6.5 When a potential non payment has been identified and notified by the accounting
authority to the service providers, the accounting authority is responsible for the debt incurred
only up to the date of notification and provided that the service providers bill all outstanding
charges within 45 working days of receipt of such notification.
Notification shall be by telex, or other confirmable means of communication, to the office
designated by the service providers.
4.8 Refunds
4.8.1 Radiotelegrams
4.8.1.1 The provisions of Recommendation D.43 shall apply with the following exceptions.
4.8.1.2 Where a radiotelegram remains undelivered after the required period of retention
(Recommendation E.200/F.110), the Service Provider may determine the basis of the refund of
charge either under the provisions of Recommendation D.43 or refund the land station charge in
full. In the second case, the Service Provider may charge a compensatory flat rate handling
charge per undelivered message.
4.8.1.3 In the case of a radiotelegram that has been forwarded by the land station to a
maritime mobile station in port by means other than radio (see Recommendation F.110), only
the land station charge shall be debited.
4.8.2 Radiomaritime letters
4.8.2.1 When a radiomaritime letter fails to reach its destination due to the failure of the postal
service, only the charges in respect to the services not carried out are refundable.
4.8.2.2 Refund of charges is applicable when, through the fault of the telegraph or
radiotelegraph service, a radiomaritime letter has not reached its destination, taking into account
Recommendation D.43.
Part E – ITU-T Rec. D.90 499
4.8.3 Radiotelephone and radiotelex calls
4.8.3.1 When, through any fault of the service, the booking of a call is not followed by the
calling and called maritime mobile stations being placed in communication, no charge shall be
payable. If the amount of the charge has been paid, it shall be refunded.
4.8.3.2 In order to simplify operating and accounting procedures, Service Providers may
decide that no charge shall be payable when a requested connection has not been set up,
whatever the reason.
4.8.3.3 However, Service Providers may decide to collect charges in cases where there is no
fault of service. In that case the basis of charging shall be notified to the Radiocommunication
Bureau for inclusion in the List of Coast Stations [1].
4.8.3.4 When, through any fault of the service, difficulty is experienced in the course of a call,
the chargeable duration of the call shall be reduced to the total time during which transmission
conditions have been satisfactory, taking account the relevant ITU-T Recommendations.
4.8.4 Radiotelexograms
4.8.4.1 The principles for refunds for radiotelegrams and telex calls shall apply as appropriate.
5 International accounting and settlement
5.1 International accounting for maritime mobile traffic to/from maritime mobile stations
arises when maritime mobile communications involve the use of a land station in a country other
than the one in which either the called or calling party is located, or where two land stations in
different countries are involved in the call (cases 3, 4, 6 ) and covers:
a) the landline charge / accounting rate;
b) the land station charge / accounting rate where applicable (cases 4, 6).
5.1.1 Landline – The international call from the land station in one country to the called
party in another country, or between two land stations in different countries. This will be
accounted at the agreed international accounting rate applying in the international relation
concerned for the service used and shall be included in the relevant international traffic accounts
in accordance with the provisions of the International Telecommunications Regulations and
relevant ITU-T Recommendations.
5.1.2 Land station – The amount is set by the LSO
5.2 A single accounting rate covering both the landline and the land station elements may
be bilaterally agreed where the origin Administration is able to record all the necessary data.
5.3 The land station administration in a country other than that where a call originates is
considered for the purposes of the landline accounting to be the origin or destination country (as
appropriate) of the call, and not as a transit point.
500 Maritime Manual
5.4 Manual or Single-Operator (LSO) Service (see Case 3 and Case 4 – VHF/HF/MF)
5.4.1 In single-operator service, subject to bilateral agreement a terrestrial customer in one
country and an LSO in another country may call each other without the intermediary of an
operator in the first country (see Recommendation F.110).
5.4.2 For traffic to a maritime mobile station which originates in a country other than that of
the land station (case 4), the land station Administration shall, unless otherwise bilaterally
agreed, debit the originating Administration with the land station charges based on data gathered
by the LSO.
5.4.3 Except where calls are made collect, the call details are forwarded by the LSO at least
monthly to the originating Administration. The amounts due are included in the periodic
statement of accounts to the credit of the land station Administration.
5.4.4 When handled through a land station, the duration for international accounting of a
manual or single-operator call will be fixed at the end of the call by the land station: if two land
stations are participating in the handling of the call, the record of the land station that accepted
the call from the originating maritime mobile station will prevail.
5.5 Automatic and semi-automatic service (see Case 4 – satellite)
5.5.1 Traffic to a maritime mobile station which has originated in a country other than that
of the land station (case 4), both the landline and the land station charges shall be included in the
relevant traffic accounts by the origin Administration on the basis of its own record of
chargeable units.
5.5.2 Accounts for charges relating to the maritime mobile satellite services shall show the
country of origin/ destination ocean area and chargeable duration/words and if possible the
number of calls/messages. Such accounts shall include the total chargeable duration for any
broadcast calls sent over the international public switched network to a land (earth) station in the
maritime mobile satellite service, separately listed.
5.6 Collect calls where permitted by the service provider are, for accounting purposes,
regarded as originating in the destination country or destination maritime mobile station as
applicable. Collect calls will be identified separately in the international accounts.
5.7 Settlement of international accounts
5.7.1 Exchange and verification of international traffic accounts and payment of balances of
those accounts shall be carried out in accordance with the International Telecommunication
Regulations and the relevant ITU-T Recommendations.
Part E – ITU-T Rec. D.90 501
Annex A
Accounting authorities (This Annex forms an integral part of this Recommendation)
Background
Accounting authorities came into existence to reduce the number of bills, both issued by Service
Providers and received by shipowners and which required extensive administrative effort to
progress, e.g. identify calls, convert call charges in various currencies and reconcile charges.
The accounting authority acts as a billing intermediary between the maritime mobile station and
service providers.
A.1 Role of an accounting authority
A.1.1 The role of an accounting authority may be undertaken by:
a) an Administration;
b) a Recognized Operating Agency (ROA);
c) any other entity or entities designated for this purpose by the Administration
referred to in a) above.
A.1.2 When acting on behalf of a maritime mobile station for which it has accepted
responsibility, an accounting authority shall be responsible for:
A.1.2.1 obtaining payment of the collection charges for maritime mobile communications
from the maritime mobile station.
A.1.2.2 guaranteeing payment of the collection charges to the service providers for traffic
originated by the maritime mobile station, ensuring that these payments are made in accordance
with the ITU Regulations and Recommendation D.90.
A.1.2.3 maintaining up-to-date and accurate records of the maritime mobile stations for which
it has responsibility. Any change in status, shipowner if known, termination/commencement of
contract must be notified immediately to interested/regularly used service providers and to the
Administration that licensed the maritime mobile station. Where changes have occurred, a new
and updated list of maritime mobile stations should be issued by the accounting authority at least
every 90 days to interested/regularly used service providers and to the Administration who
licensed the maritime mobile station, with changes to the previously issued information clearly
indicated. Alternatively, a “no change” notification may be issued. The updated information
should consist of:
– satellite identity number/ships call sign;
– ship/mobile name;
– commencement date;
– termination date;
– previous Agent or new Agent, if known;
502 Maritime Manual
– shipowner, if known.
A.1.2.4 ensuring that its Accounting Authority Identification Code (AAIC) is known by all
Administrations recognizing it and all maritime mobile stations for which it is responsible.
A.1.3 An accounting authority should notify service providers and the Administration which
has licensed the maritime mobile station concerned, as soon as it has been established that it is
unable to collect payment from that maritime mobile station. This information will enable the
service providers to cease accepting calls from that maritime mobile station in order to prevent
the uncollectable debt from further increasing.
A.1.4 The licensing Administration may authorize accounting authorities recognized by it to
notify the Radiocommunication Bureau directly of additions, modifications and deletions to be
made in the List of Ship Stations as regards maritime mobile stations for which they have billing
responsibility. Such additions, modifications and deletions should contain whenever possible,
the full details required for the List (see A.1.2.3 above). When a licensing Administration gives
such authorization, it will notify the ITU that it has done so. Before an Accounting Authority
(AA) accepts responsibility maritime mobile station which has previously been the
responsibility of another AA, the new AA jointly with the previous AA should check the
maritime mobile station’s payment record.
A.2 Registration of an accounting authority
A.2.1 An accounting authority must be registered with their Administration. Registration
should be subject to a periodic review (for example, annual) by the Administration or national
Regulatory Body of the financial position and effectiveness of each accounting authority. Should
the registration be suspended or cancelled, the registering Administration shall inform the
Radiocommunication Bureau by means of a notice for inclusion in the ITU Operational Bulletin,
that the registration has been suspended or cancelled.
A.2.2 Each accounting authority will be allocated a discrete Accounting Authority
Identification Code (AAIC – see A.3.1 below) by the registering Administration.
A.2.3 The registering Administration shall notify the name(s) and address(es) of the
accounting authority(ies) with their respective identification codes to the Radiocommunication
Bureau for inclusion in the List of Ship Stations.
A.2.4 The number of accounting authorities responsible for maritime mobile stations
licensed by an Administration shall be limited as far as possible and should not exceed 25
(whether all are based in the licensing Administration’s country or based abroad – see A.3.2.3
and A.3.4.3 below).
A.3 Identification of accounting authorities – AAICs
A.3.1 Code format
The discrete Accounting Authority Identification Code (AAIC) consists of two parts:
a) the first part will be two letters denoting the country in which the accounting
authority is based, and must be in line with those given in the official service
Part E – ITU-T Rec. D.90 503
document which is published in accordance with Recommendation F.96 (List of
Indicators for the Telegram Retransmission System). In case of doubt,
information may be obtained from the Radiocommunication Bureau.
b) the second part will be numeric, denoting the particular accounting authority.
A.3.2 Code allocation
A.3.2.1 The AAIC will be allocated by the Administration of the country in which the
accounting authority is based, regardless of whether or not the accounting authority concerned is
responsible for maritime mobile stations licensed by that Administration.
A.3.2.2 An Administration may recognize an accounting authority based in another country to
have responsibility for maritime mobile stations which it has licensed. In such cases, the
recognizing Administration shall notify this fact to the Administration of the country in which
the accounting authority is based and ask for confirmation of its AAIC.
A.3.2.3 The limitation of accounting authorities to 25 refers only to the number of accounting
authorities which an Administration may recognize to act as an accounting authority for
maritime mobile stations which it has licensed (List a). It does not necessarily apply to the
number of accounting authorities based within that Administration’s country (List b), see
A.3.4.3 below. It is possible therefore that the number of AAICs for any one country will exceed
25.
A.3.2.4 Exceptionally, an Administration may agree that an individual maritime mobile station
to be licensed by it may retain its existing accounting authority even if this is not one of those on
the licensing Administration’s List a, provided:
– that the accounting authority is one of those recognized by the Administration of
the country in which it is based for its Lists a and b; and
– prior agreement is reached between the licensing Administration and the
accounting authority concerned.
A.3.3 Notification of AAICs
A.3.3.1 An accounting authority will notify its AAIC to the Administration of each country
recognizing it as an accounting authority for maritime mobile stations which it has licensed. The
Administration concerned must include the AAIC in any notification to the ITU concerning an
accounting authority, for example, notification of an accounting authority’s address for inclusion
in the List of Ship Stations.
A.3.3.2 Each accounting authority is responsible for ensuring that all maritime mobile stations
for which it is responsible are notified of its AAIC and that these maritime mobile stations are
aware of their responsibilities as regards using the AAIC when originating maritime mobile
communications.
A.3.3.3 When an accounting authority accepts responsibility for a maritime mobile station
which may previously have been the responsibility of another accounting authority, it must
ensure that the maritime mobile station is advised immediately of the new AAIC to be used.
504 Maritime Manual
A.3.4 Publication of AAICs
A.3.4.1 The Administration of the country in which the accounting authority is based is
responsible for notifying the ITU of the AAIC allocated.
A.3.4.2 An Administration that accepts an accounting authority outside its own country for
maritime mobile stations under its flag, is responsible for notifying the ITU of this fact and of
the AAIC allocated to that accounting authority.
A.3.4.3 The information should be published in the ITU List of Ship Stations, List V, in a
special section with the following sub-sections:
– Sub-section A – Alphabetical listing of all accounting authorities by order of their
AAICs, giving their names, addresses, telephone and telefax numbers.
– Sub-section B – Alphabetical listing of all accounting authorities by their names,
giving their AAICs and addresses, telephone and telefax numbers.
– Sub-section C – Alphabetical listing of countries, with the following entries under
each country:
• List a: accounting authorities, by AAICs code, responsible for maritime
mobile stations licensed by that country’s Administration (maximum of
25 AAICs);
• List b: accounting authorities, by AAICs code, based in that country (list
may exceed 25).
A.3.4.4 From these three sub-sections, it will be possible to:
i) extract the name and address of an accounting authority when only the AAIC is
known;
ii) find the AAIC when only the name and address are known; and
iii) determine which accounting authorities are recognized as acting for maritime
stations of a particular registry.
A.3.4.5 In the body of the ITU List of Ship Stations, the AAIC of the accounting authority
concerned should be shown against each maritime mobile station’s entry.
Part E – ITU-T Rec. D.90 505
A.3.4.6 Examples
Allocation of Accounting Authority Identification Code (AAIC)
BRM
List a* BE02 BM01 BM02
BM03 CY03 DP02
JP02 JP03
List b** BM01 BM02 BM03
* Indicates accounting authorities, by their discrete AAIC, authorized to account for Ship
Stations licensed by the Administration of the country and is limited to a maximum of 25.
** Indicates accounting authorities, by their discrete AAIC, based within the country and there
is no limit to the number of listing per country.
Country that licensed the maritime mobile
station
Country where the accounting authority is based and where the AAIC is allocated (see A.3.2.1)
Accounting authority is one of the maximum of 25 (A.2.4) designated by:
AAIC
Netherlands Netherlands Netherlands NL...
Netherlands United Kingdom Netherlands GB...
United Kingdom Netherlands United Kingdom NL...
Belgium Netherlands Belgium NL...
Belgium Belgium Belgium BE...
etc.
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Annex B
Specimen statement of maritime communication bill
“Summary” Page – see 4.4.3
(This annex forms an integral part of this Recommendation)
(Preferably on paper size 210 × 297 mm)
____________
1) “The Communications Information Statements” and the associated “Summary Statement” should be
identified by the same unique bill number.
2) This should be the actual date of dispatch and not the date when the bill is raised.
...............................: (Sender of bill) Date of dispatch2)
Accounting authority: (Recipient of bill)
STATEMENT OF MARITIME COMMUNICATION – SUMMARY Page:
Period (MMYY):
Bill number1):
Category:
Name of maritime mobile station
Call sign Maritime mobile
station ID Amount due*
ALFA 511 1234 100.00
HOTEL 311 1234 200.00
MIKE 111 1234 500.00
ROMEO 211 1234 200.00
ZULU 411 1234 200.00
Total amount due 1200.00
* Expressed in Monetary Unit: SDR or GFR (1 SDR is equivalent to 3.061 GFRs).
Part E – ITU-T Rec. D.90 507
Annex C
Specimen statement of maritime communication bill
“Communication Information” Statement – see 4.4.3 (This annex forms an integral part of this Recommendation)
(Separate statement for each mobile station)3)
For a description of service and facility codes to be used, see Annex A/D.91, Appendices I/D.91
and II/D.91.
____________
3) Exceptionally, this statement may contain data on more than one maritime mobile station where the
volume of traffic for each maritime mobile station is low.
4) This should be the actual date of dispatch and not the date when the statement was raised.
...............................: (Sender of bill) Date of dispatch4)
Accounting authority: (Recipient of bill)
Bill number: Page:
STATEMENT OF MARITIME STATION BILLS for Mobile Station: ALFA
Call sign: 5Bxxx
Maritime mobile station identification:
Date/time Land station Destination Chargeable unit
(Duration/words)Service
type Amount due*
Remarks*/special services
30.00
5.00
10.00
15.00
40.00
Total amount due 100.00
* Expressed in Monetary Unit: SDR or GFR (1 SDR is equivalent to 3.061 GFRs).
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Part E – ITU-T Rec. F.60 509
ITU-T Recommendation F.60
OPERATIONAL PROVISIONS FOR THE INTERNATIONAL TELEX SERVICE
(revised 1992)
3 Operation of the international telex service
TABLE 1/F.60
Expanded form of DER code expression
a) These characters may appear anywhere on the line preceding the DER signal and are an integral part of the expanded service signal.
b) Or technical failure presenting the same condition at the exchange.
Note 1 – The implementation of these expanded forms of the service signal is a national matter.
Note 2 – See also Recommendation U.45.
3.6 Subscribers’ operating procedure for telex calls
3.6.1 Administrations may wish to advise their customers on how to make best use of the
international telex service. To that end, an example for such provisions is given in Annex A.
Such instructions may also include information regarding the code expressions used in the
international telex service, which are listed in § 4.1 and which could usefully be inserted within
national telex directories.
4 Miscellaneous provisions
4.1 Code expressions used in the international telex service
4.1.1 The following code expressions may be used in operator-to-operator correspondence,
generated by the network or used by the originating subscriber for special purposes. In certain
Code
expression
Additional information
characters a)Meaning b)
EXM Out of order due to no text recording medium
DER NAB Out of order due to failure of answerback mechanism
PFL Out of order due to no power at the called terminal
510 Maritime Manual
cases, they may also be followed by the clear signal. Subscribers may also find it useful to use
some of these codes during a conversational call.
ABS Absent subscriber/office closed
ADD Please input your international telex number
ANUL Delete
BCT Broadcast call
BK I cut off
BMC No end of message or end of transmission received, therefore message
cancelled
CFM Please confirm/I confirm
CI4) Conversation impossible
COL5) Collation please/I collate
CRV Do you receive well?/I receive well
DER Out of order (see Table 1/F.60)
DF You are in communication with the called subscriber
EXM Connection cleared due to exhaustion of text recording medium at
either the called or calling terminal
FMT Format error
GA You may transmit/May I transmit?
IAB Invalid answerback from destination
IMA Input message acknowledgement
INF Subscriber temporarily unobtainable, call the information service
ITD Input transaction accepted for delivery
ITL I transmit later
JFE Office closed because of holiday
LDE Maximum acceptable message length or duration has been exceeded
MNS Minutes
MOM Wait/waiting
MUT Mutilated
NA Correspondence with this subscriber is not admitted
NC No circuits
NCH Subscriber’s number has been changed
_______________4)
This code expression is intended to be generated only by automatic means and not normally used in
service correspondence between operators.
5) Repetition of, for example, isolated figures, mixed figures or other sensitive information.
Part E – ITU-T Rec. F.60 511
NDN Non-delivery notification
NI No line identification available
NP The called party is not, or is no longer, a subscriber
NR Indicate your call number/My call number is . . .
OCC Subscriber is engaged
OK Agreed/Do you agree?
PPR Paper
R Received
RAP I shall call you back
RDI Redirected call
REF Reference of the message delivered to the telex side from a conversion
facility for telex/teletex interworking
REI Address validation failure/non-compliant answerback received
RPT Repeat/I repeat
RSBA Retransmission still being attempted
SSSS Change of alphabet
SVP Please
T6) Stop your transmission
(or figure 5)6)
TAX What is the charge?/The charge is . . .
TEST MSG Please send a test message
THRU You are in communication with a telex position
TMA Maximum number of addresses exceeded
TPR Teleprinter
TTX Designation of the conversion facility (CF) for telex-teletex
interworking
VAL Validation response
W Words
WRU Who is there?
XXXXX Error
_______________6)
To be repeated until the transmission is brought to a stop.
512 Maritime Manual
ANNEX A
(to Recommendation F.60)
Operating procedure for telex calls
A.1 Setting up a telex call
A.1.1 In the automatic service the subscriber selects the telex number required. The
establishment of a connection is recognized by the reception of the answerback from the wanted
subscriber. The caller should check whether the answerback he has received is in fact that of the
appropriate subscriber. If it is not, he should disconnect and reselect the number of the
subscriber required. When the caller has received the correct answerback he should release his
own answerback before starting the transmission of a message.
A.1.2 In the manual or semi-automatic service a connection is established through the
intermediary of an international telex position. The establishment of a connection is indicated by
the reception of the answerback from the called subscriber, followed by that of the calling
subscriber. The subscribers must not intervene during this procedure. The caller checks whether
the answerback he has received is in fact that of the wanted subscriber. If it is not, he should
disconnect and inform the international telex position accordingly.
A.1.3 If the called telex station is continuously unattended, e.g. automatic answering
equipment, store-and-forward equipment or other reception equipment, a dialogue with the
called telex station is impossible.
A.1.4 If the telex machine of the called subscriber is attended, a dialogue between
subscribers is possible, in which case the end of each transmission should be indicated by the
plus sign and question mark (+?) followed by a letter-shift, thus inviting the other party to
transmit in his turn.
A.2 Setting out the message
A.2.1 Where the recipient may be in doubt about the identity of the caller, it is recommended
that the calling subscriber indicate:
a) name and place of the sender, preceded by the word FROM;
b) name and place of the addressee, preceded by the word TO;
c) if required, name and place of information addressee(s), preceded by the word
COPY.
Practice has shown that the observation of this recommendation will often save
additional work for the recipient especially when messages have to be distributed for action.
A.2.2 After the exchange of answerbacks as set out in § A.1 and following the
recommendation in § A.2.1, the calling subscriber can transmit his message, for which the
following uniform procedure is recommended:
a) start a new line and mention own reference, if any, and the date of dispatch;
b) start a new line and indicate the priority of the message, if desirable, such as
URGENT, VERY URGENT, etc.;
Part E – ITU-T Rec. F.60 513
c) start a new line and indicate the subject if appropriate and/or the name of the
person or department for whose attention the message is intended;
d) start a new line and mention any references, such as REF YOUR TELEX 123
OF 15.7, REF YOUR LETTER 456 OF 25.7, REF OUR TELECON, etc.;
e) start a new line and transmit the text of the message;
f) after having completed the message, start a new line and transmit a plus sign (+)
indicating the end of the message or NNNN;
g) obtain the answerback of the called subscriber, check it in order to be sure that the
connection is still in good order and generate own answerback;
h) if there are more messages, they should be separated from each other by at least 8
line-feeds, after the exchange of the answerbacks as mentioned in g);
i) after transmission of the last message and the exchange of the answerbacks send
at least 8 line-feeds and give the clearing signal.
A.3 Additional instructions
A.3.1 When a group, or part of a group, is composed of a whole number and an ordinary
fraction, the fraction should be separated from the number by means of a dash without space.
Example: for one and three quarters: 1-3/4
A.3.2 In order to avoid misunderstanding, a whole number, a fractional number, or a fraction
followed by a % or %o should be transmitted by joining them up to the % or %o. sign by a dash,
or transmitted in full as appropriate.
Examples: for 2% transmit 2-0/0 or 2 PER CENT
Examples: for 4 ½ %o, transmit 4-1/2-0/00 or 4-1/2 PER MILLE
A.3.3 When important figures or words appear in the text it is desirable to repeat them
immediately after the group followed by a space either in brackets or preceded by the word
REPEAT.
Examples: 1500 (1500)
Examples: 1500 REPEAT 1500
Examples: NOT REPEAT NOT
A.3.4 To pass to the beginning of the next line, i.e. to start a new line, first press carriage-
return and then line-feed. Some terminals may also provide a new line key which combines
these functions.
A.3.5 An error is corrected in the following manner:
a) In manual transmission, by the sequence XXXXX (letter X repeated five times
and followed by a space)7) joined to the erroneous word.
_______________7)
It is to be noted that the sequence E E E (space and letter E repeated three times followed by a space
and repetition of the last correct word) is in use but is not preferred.
514 Maritime Manual
Example: PLEASE DISPATCH FITXXXXX FIVE PARCELS
b) In automatic transmission, when preparing perforated tape, by backspacing (if
necessary by counting the number of characters to be erased, including spaces
and shifts, and backspacing by that number) to the erroneous character and then
operating the letter-shift key to erase all the characters up to and including the last
punched character. Then start again with the character to be sent immediately
after the last correctly punched character.
c) If the procedure mentioned under b) for one reason or other cannot be followed,
an error could be corrected as indicated under a).
d) If an error is detected after the transmission of a message but before the exchange
of the answerbacks it should be corrected by clearly indicating under the text of
the message what change is required, e.g.:
CORRECT 4TH WORD 2ND LINE TO READ NOT REPEAT NOT
DELETE 4TH WORD 2ND LINE
INSERT THE WORD “WITH” BETWEEN THE 4TH AND 5TH WORD
OF 2ND LINE
A.3.6 If, for some reason or other, a message has to be cancelled during transmission this
should be clearly indicated on a new line by transmitting three times the word ANUL.
A.3.7 In preparing a perforated tape for automatic transmission, care should be taken that:
a) the signal Who are you? (figure case D) does not appear on the tape, in order to
prevent the text from being garbled by the returned answerback of the other party;
b) the procedure mentioned in § A.3.4 above is followed;
c) the tape is perforated to the end with a series of letter-shifts.
A.3.8 Since figure case signs or letters coupled with the letters F, G and H are not
universally standardized, they must not be used in international communications, but should be
transmitted in full, e.g. DOLLARS, POUNDS STERLING, etc.
A.4 Ineffective call attempts when calling from a manual terminal
A.4.1 If an attempt to set up a call is unsuccessful (for example, if the wanted subscriber is
engaged), the network will return a service code indicating the reason. It will also disconnect
automatically except in the particular cases of changed number interception and call redirection
as described in Recommendation U.41.
A.4.2 The commonly used service codes, their meaning and the appropriate action for the
subscriber to take are given in Table A-1/F.60.
A.5 Idle connections
A.5.1 To avoid incurring unnecessary charges, care should always be taken to clear the
connection once all messages have been sent (see § A.2.2).
Part E – ITU-T Rec. F.60 515
A.5.2 In some national telex networks a prolonged idle condition may cause a warning
message to appear followed, possibly after a short delay, by clearing. Normally, this action will
not commence until the idle condition has persisted for a period to be determined by the
Administration.
A.5.3 Should a subscriber wish to maintain an idle condition for a period in excess of that
stipulated by the Administration, it is advisable to make that intention clear by sending at least
one character periodically.
TABLE A-1/F.60
Procedure after ineffective call attempts when calling from a manual terminal
Note – Recommendation U.40 describes the procedure after ineffective call attempts when calling from an automatic telex terminal.
Service
code
Meaning What to do
OCC The called subscriber is engaged
NC No circuits (or equipment) are available at
the moment
Wait for at least one minute, then call
again
DER Called subscriber’s terminal is out of order,
or temporarily out of service whilst paper,
ribbon or tape is replaced
Check the number and try again after
about 5 minutes. If DER persists, refer
the problem to the Telex Enquiries
Service
ABS
NA
NP
NCH
Called subscriber is absent. Office is closed
Access to called service not admitted
The called number is not, or is no longer, a
working line
Called susbcriber’s number has been
changed (NCH may be followed by the new
number)
Check the number. If correct, try again.
If the same service signal is returned
refer the problem to the Telex
Enquiries Service
516 Maritime Manual
ITU-T Recommendation F.110
OPERATIONAL PROVISION FOR
THE MARITIME MOBILE SERVICE
(revised in 1996)
DIVISION A – GENERAL
3 Definitions
A4 3.1.1 controlling operator: The controlling operator is the first land-based
operator handling the radiotelegram, radiotelex call or radiotelephone call in the
direction from the mobile station.
A5 3.1.2 accounting authority identification code: An accounting authority
identification code is assigned to each accounting authority (defined in the
International Telecommunication Regulations [1]). In effect the accounting authority
acts as a billing intermediary between mobile stations and ROAs.
A6 3.1.3 recognized operating agency (ROA): The term is defined in the
International Telecommunication Constitution (Geneva, 1992) [2]. For the purpose of
this CCITT Recommendation an ROA is, in effect, any individual, company,
corporation or governmental agency that operates an international telecommunication
service to carry public correspondence (as defined in the Constitution). Each ROA is
authorized by an ITU Member, which imposes certain obligations on the ROA. (For
further details, see the Constitution.)
A12 3.1.9 ship station identity: Ship’s identification X1, X2 ... Xn identifying the ship
uniquely. The ship station identity may be transmitted on the radio path.
A13 3.1.10 coast station identity: The coast station identification X1, X2 ... Xn
transmitted on the radio path.
4 Order of priority
A15 4.1 The order of priority for communications in the maritime mobile service
shall be as follows, except where impracticable in a fully automated system in which,
nevertheless, communications described in A16 shall receive priority:
A16 a) distress calls, distress messages and distress traffic;
A17 b) communications preceded by the urgency signal;
A18 c) communications preceded by the safety signal;
Part E – ITU-T Rec. F.110 517
A19 d) communications relating to radio direction-finding;
A20 e) communications relating to the navigation and safe movement of aircraft engaged
in search and rescue operations;
A21 f) communications relating to the navigation, movements and need of ships, aircraft
and weather observations messages destined for an official meteorological
service;
A22 g) radiotelegrams relative to the application of the United Nations Charter
(ETATPRIORITE);
A23 h) government radiotelegrams with priority (ETATPRIORITE) and government
calls for which priority has been expressly requested;
A24 i) ordinary private radiotelegrams and RCT radiotelegrams for which urgent
transmission and delivery has been requested;
A25 j) service communications relating to the operation2) of the telecommunication
service or to communications previously exchanged;
A26 k) government communications other than those shown in A29 ordinary private
communications and RCT radiotelegrams;
A27 l) radiomaritime letters.
DIVISION B – RADIOTELEGRAMS
1 Preparation and handing-in of radiotelegrams
1.1 Indication of station of origin
B1 1.1.1 When, because of duplication of names, the name of a station is followed by
its call sign/ship station identity, the latter shall be joined to the name of the station by
a fraction bar.
Examples3): OREGON/OZOC (not OREGONOZOC);
ROSE/DDOR (not ROSEDDOR).
_______________2)
For the operational aspects of service telecommunications, see Recommendation F.17, which describes
basic principles, acceptable content for service telecommunications and the principle of reciprocity
regarding both service providers and services. More detailed provisions for specific telecommunication
services may be found in Recommendations F.105, F.1 and F.60.
3) In the provision regarding the non-voice services, letters, figures and signs that are transmitted
electrically are shown in bold font.
518 Maritime Manual
B2 1.1.2 When a land station retransmits a radiotelegram received from a mobile
station, it shall transmit, as office of origin, the name of the mobile station in which the
radiotelegram originated as this name appears in the List of Ship Stations [5], followed
by its own name. Where appropriate, B1 shall also apply.
B3 1.1.3 In order to avoid any confusion with a telegraph office or a fixed station of
the same name, the land station may, if desirable, complete the indication of the name
of the mobile station of origin by the word SHIP or AIRCRAFT, placed before the
station of origin.
1.2 Use of accounting authority identification codes by mobile stations
B4 1.2.1 The mobile station operator should, as a standard operating procedure, give
the Accounting Authority Identification Code (AAIC) at the end of the preamble line.
If the AAIC is missing, the land station operator should request QRC.
1.3 Time of handing-in
B5 1.3.1 In the transmission of radiotelegrams originating in a mobile station, the date
and time of handing-in at this station are given by two groups of figures in the
preamble line, the first indicating the day of the month (1 to 31) and the second
consisting of a group of figures (0001 to 2400) indicating the hours and the minutes.
B6 1.3.2 The time of handing-in is indicated in Coordinated Universal Time (UTC).
NOTE – For practical operating purposes, UTC may be considered as equivalent to Greenwich Mean Time (GMT).
1.4 Address
B7 1.4.1 The address of radiotelegrams destined for mobile stations should be as
complete as possible and must include:
B8 a) the name or the designation of the addressee, with supplementary particulars, if
necessary;
B9 b) the name of the mobile station followed, when necessary, by its call sign/ship
station identity, the latter joined by a fraction bar to the name of the station as
shown in the List of Ship Stations [5];
B10 c) the name of the land station through which the radiotelegram is to be forwarded,
as it appears in the List of Coast Stations [4].
B11 1.4.2 If the mobile station does not appear in the List of Ship Stations [5], the
sender should, if possible, indicate the nationality and route followed by the mobile
station.
Part E – ITU-T Rec. F.110 519
B12 1.4.3 However, the name and call sign/ship station identity required under B10
may be replaced, at the risk of the sender, by particulars of the passage made by such a
mobile station, indicated by the names of the ports or airports of departure and of
destination, or by any equivalent indication.
B13 1.4.4 Mobile stations may add to the name of the office of destination:
– the name of the territorial subdivision; and/or
– the destination country,
if it is doubtful whether, without such addition, the radiotelegram could be correctly
routed without difficulty.
B14 1.4.5 The controlling operator retains or deletes the particulars in B13 or further
amends the name of the office of destination as is necessary or sufficient for
forwarding the radiotelegram to its proper destination.
2 Counting of words
B15 2.1 The word count of the office of origin is decisive in the case of
radiotelegrams destined for mobile stations, and that of the controlling operator is
decisive in the case of radiotelegrams originating in mobile stations.
B16 2.2 If two land stations participate in the handling of a radiotelegram, the
decision of the controlling operator accepting the radiotelegram from the originating
mobile station will prevail and will be valid for international accounting.
3 Routing of radiotelegrams
B17 3.1 Radiotelegrams, originating in or destined to a mobile station should be
routed via the land station that is considered most suitable in relation to the mobile
station concerned in terms of the coverage and of the land station and radio conditions.
B18 3.2 However, to expedite or to facilitate the routing of radiotelegrams to a land
station, a mobile station may transmit them to another mobile station. The latter shall
dispose of such radiotelegrams in the same manner as if they originated with itself (see
B39 to B42).
B19 3.3 If the sender of a radiotelegram handed in at a mobile station has indicated
the land station to which the radiotelegram be sent, the mobile station shall, in order to
effect this transmission to the land station indicated, wait, if necessary until the
conditions specified in B17 and B18 are fulfilled.
B20 3.4 In order to facilitate disposal of traffic, and subject to such conditions as
individual ROAs may apply, land stations may, in exceptional circumstances and with
discretion, without incurring additional charges, exchange radiotelegrams and service
telegrams relating thereto.
520 Maritime Manual
4 Transmission of radiotelegrams
4.1 Routine repetition
B21A 4.1.1 Routine repetition means the repetition of isolated figures and mixed groups
containing figures in the address and text parts. Any such repetition should be given
after the text part and be preceded by the code COL.
B21B 4.1.2 In view of CCITT Recommendation F.1 (A103) routine repetition may be
used between land station and mobile station at the discretion of the sending station
where the transmission conditions warrant it.
B21C 4.1.3 Where a mobile station gives a routine repetition, the land station shall use
the repeated groups to check the received address and text parts, but should not
retransmit the routine repetition.
4.2 Doubtful reception
B22 4.2.1 In the mobile service, when communication becomes difficult, the two
stations in communication should make every effort to complete the radiotelegram in
course of transmission. The receiving station may request not more than two
repetitions of a radiotelegram of which the reception is doubtful.
B23 4.2.2 If this triple transmission is ineffective, the radiotelegram is kept on hand in
case a favourable opportunity for completing its transmission occurs.
B24 4.2.3 If the transmitting station considers that it will not be possible to re-establish
communications with the receiving station within twenty-four hours, it proceeds as
follows:
B25 4.2.4 If the transmitting station is a mobile station, it immediately informs the
sender of the reason for the non-transmission of his radiotelegram. The sender may
then request:
B26 a) that the radiotelegram be transmitted through another land station or through
other mobile stations; or
B27 b) that the radiotelegram be held until it can be transmitted without additional
charge; or
B28 c) that the radiotelegram be cancelled.
B29 4.2.5 If the transmitting station is a land station, it applies the provision of B43 to
B52 to the radiotelegram.
B30 4.2.6 When a mobile station subsequently transmits a radiotelegram thus held to
the land station that incompletely received it, this new transmission must bear the
service instruction AMPLIATION at the end of the preamble line of the
radiotelegram.
Part E – ITU-T Rec. F.110 521
B31 4.2.7 However, if the radiotelegram is transmitted to another land station operated
by the same ROA, the new transmission must bear, at the end of the preamble line, the
service instruction AMPLIATION VIA ... (insert here the call sign/coast station
identity of the land station to which the radiotelegram was transmitted in the first
instance) and the ROA in question may claim only the charges relating to a single
transmission.
B32 4.2.8 The other land station, which thus forwards the radiotelegram, may claim
from the mobile station of origin any additional charges resulting from the
transmission of the radiotelegram between itself and the office of destination.
B33 4.2.9 When the land station designated in the address as the station by which the
radiotelegram is to be forwarded cannot reach the destination mobile station and has
reason to believe that such mobile station is within the service area of another land
station of the ROA by which it is operated, it may, if no additional charge is incurred
thereby, forward the radiotelegram to this other land station.
B34 4.2.10 A station of the mobile service that has received a radiotelegram and has
been unable to acknowledge its receipt in the usual way must take the first favourable
opportunity to give such acknowledgement.
B35 4.2.11 When the acknowledgement of receipt of a radiotelegram transmitted
between mobile station and land station cannot be given directly, it is forwarded
through another mobile or land station by service advice (see Recommendation F.1,
Division D) if the latter is able to communicate with the station that has transmitted the
radiotelegram in question. In any case, no additional charge shall result.
4.3 Long distance radiocommunications
B36 4.3.1 An ROA may organize a long-distance radiocommunication service between
land station and mobile stations, with deferred acknowledgement of receipt or without
any acknowledgement of receipt.
B37 4.3.2 Each ROA designates the land station or stations participating in the long-
distance radio service. An indication to this effect shall appear in the List of Coast
Stations [4].
B38 4.3.3 When there is doubt about the accuracy of any part of a radiotelegram
transmitted under either of the systems mentioned in B36, the indication doubtful
reception is entered on the copy delivered to the addressee, and the doubtful words or
groups of words are underlined. If words are missing, blanks are left in the places
where these words should be.
4.4 Routine retransmission by mobile stations
B39 4.4.1 When a land station cannot reach the mobile station for which a
radiotelegram is destined, the land station may, in order to forward the radiotelegram
to its destination, have recourse to the help of another mobile station provided that the
latter consents. The radiotelegram is then transmitted to this other mobile station. The
help of the latter is given free of charge.
522 Maritime Manual
B40 4.4.2 The same provision is also applicable to traffic from mobile stations to land
stations, when necessary.
B41 4.4.3 The station assisting in the free retransmission in accordance with B39 and
B40 must enter the service abbreviation QSP ... (name or call sign/ship station identity
of the mobile station) at the end of the preamble line of the radiotelegram.
B42 4.4.4 In order that a radiotelegram thus forwarded may be considered as having
reached its destination, the station that has made use of this indirect route must have
obtained the regular acknowledgement of receipt, either direct or by an indirect route,
from the mobile station for which the radiotelegram was destined or from the land
station to which it was to be forwarded, as the case may be.
4.5 Period of retention of radiotelegrams at land stations
B43 4.5.1 When it has not been possible for a land station to transmit a radiotelegram
to a mobile station by the morning of the fifth day (not including the day of handing-
in), the land station treats the radiotelegram as undelivered and notifies the office of
origin accordingly.
B44 4.5.2 The sender of a radiotelegram destined for a mobile station may specify the
number of days during which the land station may hold the radiotelegram. In that case,
the service indication Jx (x days), specifying the number of days (ten at the most)
exclusive of the day of handing-in of the radiotelegram, shall be shown before the
address. When it has not been possible for a land station to transmit a radiotelegram
bearing the service indication Jx within the prescribed period, the land station treats
the radiotelegram as undelivered and informs the office of origin accordingly.
B45 4.5.3 The periods mentioned in B43 and B44 shall be ignored if the land station is
sure that the mobile station will soon come within its service area.
B46 4.5.4 On the other hand, the lapse of those periods is not awaited when the land
station is sure that the mobile station, being in course of a voyage, either has definitely
left its service area or will not enter it.
B47 4.5.5 If there is reason to believe that no other land station of the ROA by which it
is operated is or will be in touch with it, the land station cancels the radiotelegram as
far as concerns the section between itself and the mobile station and informs the office
of origin, which notifies the sender.
B48 4.5.6 In the contrary case, the land station forwards the radiotelegram to the land
station believed to be in touch with the mobile station, provided, however, that no
additional charge results therefrom.
B49 4.5.7 The land station that carries out the redirection alters the address of the
radiotelegram by placing after the name of the mobile station that of the new land
station charged with the transmission and adding at the end of the preamble line the
service instruction REDIRECTED FROM ... RADIO, which must be transmitted
throughout the course of the radiotelegram.
Part E – ITU-T Rec. F.110 523
B50 4.5.8 If, within the limits of the requisite period of retention of radiotelegrams, the
land station that has redirected a radiotelegram to another land station is subsequently
in a position to transmit the radiotelegram direct to the destination mobile station, it
does so by inserting the service instruction AMPLIATION at the end of the preamble
line.
B51 4.5.9 It shall then transmit to the land station to which the radiotelegram had been
redirected a service advice informing the latter of the transmission of the said
radiotelegram.
B52 4.5.10 When a radiotelegram cannot be transmitted to a mobile station owing to the
arrival of the latter in a port near the land station, the latter station may, according to
circumstances, forward the radiotelegram to the mobile station by other means of
communication, at the same time informing the office of origin by service advice of
the delivery.
5 Advice of non-delivery
B53 5.1 When, for any reason, a radiotelegram originating in a mobile station and
destined for a place on land cannot be delivered to the addressee, a service advice of
non-delivery is addressed to the land station or the telegraph office that received the
radiotelegram.
B54 5.2 After checking the address, the land station forwards the service advice,
when possible, to the mobile station, if necessary by way of another land station of the
same country or of a neighbouring country, as far as existing conditions or special
agreements permit.
B55 5.3 When a radiotelegram received at a mobile station cannot be delivered, that
station so informs the office or mobile station of origin by a service advice.
B56 5.4 In the case of a radiotelegram originating on land, this service advice is sent,
whenever possible, to the land station through which the radiotelegram passed, or, if
necessary, to another land station of the same country or of a neighbouring country, as
far as existing conditions or special arrangements permit.
B57 5.5 In such cases the name or call sign/ship station identity of the station from
which the radiotelegram was received is quoted.
6 Radiomaritime letters
B58 6.1 An ROA may organize a service of radiomaritime letters between mobile
stations and its land stations.
B59 6.2 Such correspondence is transmitted by radio between mobile and land
stations.
B60 6.3 They may be forwarded on the land section:
524 Maritime Manual
B61 a) wholly or partly by post (ordinary or airmail);
B62 b) exceptionally by telefax or other electronic means, but with low priority.
B63 6.4 Routine retransmission by mobile stations of radiomaritime letters is not
permitted.
B64 6.5 Radiomaritime letters shall be addressed only to places in the country in
which the land station is situated, unless the List of Coast Stations [4] indicates that the
station concerned will accept such traffic for onward transmission by post to places in
other countries.
B65 6.6 Radiomaritime letters bear the service indication SLT. This indication
precedes the address.
B66 6.7 Except as otherwise provided in B58 to B68, radiomaritime letters may be
accepted, taking into account ITU-T CCITT Recommendations relating to letter
telegrams if the telegram service is used to convey radiomaritime letters.
B67 6.8 The address must enable delivery to be effected without enquiry or requests
for information. Registered or abbreviated code addresses may be accepted where B62
above applies, exceptionally, radiomaritime letters are forwarded by means of
telegram on the land section.
B68 6.9 Radiomaritime letters rank, for radio transmission, after ordinary
radiotelegrams on hand. Those that have not been transmitted within 24 hours of
handing-in are sent concurrently with ordinary radiotelegrams.
7 Special services
B69 7.1 Telegrams with special services of urgent transmission and de luxe form are
admitted, provided that the ROAs concerned accept them.
8 Special conditions relating to the maritime mobile-satellite service
B70 8.1 In the maritime mobile-satellite service radiotelegrams should normally be
transmitted by radiotelex only.
B71 8.2 The radiotelegram service in B70 should be arranged in such a way that
automatic retransmission is possible.
Part E – ITU-T Rec. F.110 525
DIVISION C – RADIOTELEX
1 General
1.1 Routing of calls
C1 1.1.1 A radiotelex call, originating in or destined to a mobile station should be set
up via the land station that is considered to be most suitable in relation to the mobile
station concerned in terms of the coverage and of the land stations and radio
conditions.
C2 1.1.2 For radiotelex calls in the direction from land station to mobile station,
originator should give, if possible, the approximate geographical position and should
also indicate the land station to be used unless the ROA has established a specific
route to be followed. Such requests should be respected as far as is practicable.
C3 1.1.3 For radiotelex calls in the direction from mobile station to land station, the
mobile station may call a particular land station it desires to use. This land station
should either handle the call itself or advise the mobile station to use another land
station that is more suitable.
1.2 Information to be supplied, as necessary by the calling party
C4 1.2.1 Calls from a subscriber of the international telex service to a mobile station:
a) international telex number and/or answer-back code of the calling telex
subscriber;
b) telex number or mobile station number of the destination mobile station;
c) name or call sign/ship station identity of the destination mobile station;
d) international telex number and/or name of the land station to be used, or the
approximate geographical position of the destination mobile station;
e) priority when specifically requested.
C5 1.2.2 Calls from a mobile station to a subscriber of the international telex service:
a) telex number or mobile station number of the calling mobile station;
b) the Accounting Authority Identification Code (AAIC) in accordance with CCITT
Recommendation D.90 in the single-operator or manual operation;
c) destination country and/or network;
d) telex number and/or answer-back code of the destination telex subscriber;
e) priority when specifically requested.
C5A 1.2.3 C4 and C5 above apply to mobile station-to-mobile stations calls as
appropriate.
526 Maritime Manual
1.3 Call duration
C6 1.3.1 The chargeable duration of a call will be fixed at the end of the call:
a) by the controlling operator for a call originating from a mobile station;
b) for a call originating in the international telex service;
– by the land station operator in either manual or single-operator operation;
– by the operator of the international position of the originating country in the
semi-automatic operation.
C7 1.3.2 For a call originating from a mobile station and where two land stations
participate in the handling of the call, the decision of the controlling operator who has
accepted the call from the originating mobile station shall prevail.
C8 1.3.3 Should service difficulties be experienced in the course of a call, the
chargeable duration shall be reduced automatically or manually to the total time during
which transmission conditions were satisfactory, taking into account ITU-T
Recommendations (F.60 and F.61).
1.4 Validity of requests
C9 1.4.1 For a call to a mobile station where it becomes obvious that the required
mobile station cannot be reached by the land station, the originating telex subscriber
should be informed as soon as possible in order to have the opportunity to have the
call cancelled if required. In any event, the caller should be informed no later than in
the morning of the second day following the day on which the call request was made.
C10 1.4.2 In the automatic service any information concerning unsuccessful call
attempts shall be provided to the calling subscriber using the service signal format
described in Recommendation F.60. The period of validity for store-and-forward
messages in the automatic service shall be in accordance with Recommendation F.72.
1.5 Exchange of radiotelegrams by radiotelex
C11 1.5.1 Stations of the maritime mobile service that are equipped for radiotelex may
transmit and receive radiotelegrams by means of radiotelex.
C12 1.5.2 Stations of the maritime mobile-satellite service should normally transmit
and receive radiotelegrams by means of radiotelex only.
2 Traffic from mobile stations to subscribers of the international telex
service
2.1 Automatic operation
C13 2.1.1 Whenever possible, fully automatic procedures should be used.
Part E – ITU-T Rec. F.110 527
C14 2.1.2 For a call originating from a mobile station and after connection with the
desired land station is established, the mobile station should forward the international
telex number, including the telex destination code in accordance with
Recommendation F.69. The selection procedures for calls from a mobile station in the
maritime mobile-satellite service to a subscriber of the international telex service are
described in clause 6 of Division C.
2.2 Single-operator operation
C15 2.2.1 The land station operator should select the destination telex subscriber
directly via the international telex network if fully automatic procedures (C13) are not
possible.
2.3 Semi-automatic operation
C16 2.3.1 The destination telex subscriber should be automatically selected if fully
automatic procedures (C13) or single operator procedures (C15) cannot be applied.
2.4 Manual operation
C17 2.4.1 The land station operator should apply manual procedures if fully automatic
(C13), single-operator (C15) or semi-automatic (C16) procedures are not possible.
2.5 Store-and-forward service
C17A 2.5.1 The mobile station should transmit the message to the land station using
automatic procedures. The land station should forward the message via the
international telex network to the destination telex subscriber.
C17B 2.5.2 The procedures for store-and-forward in the operation international telex
network, as laid down in Recommendations F.72, U.80 and U.81, should be taken into
account.
2.6 Operational procedures
C18 2.6.1 The manual, semi-automatic and fully automatic procedures for the
international telex service, as laid down in Recommendations F.60 and F.61, should be
taken into account.
3 Traffic from subscribers of the international telex service-to-mobile
stations
3.1 Fully automatic operation
C19 3.1.1 Whenever possible fully automatic procedures should be used.
528 Maritime Manual
C20 3.1.2 A subscriber of the international telex service should forward the
international telex number of the destination mobile station including the mobile
station number and if necessary the telex destination code of the ocean region in which
the mobile station is thought to be located. The call will then be routed, through an
appropriate land station to the destination mobile station. The selection procedures for
calls from a subscriber of the international telex service to mobile earth station are
described in clause 6 of Division C.
C21 3.1.3 If the originating telex subscriber, for some technical reason, cannot use
fully automatic procedures to establish contact with the mobile station, semi-automatic
(C35) or single-operator (C24) procedures should be used.
C22 3.1.4 On international telex links a destination code in accordance with
Recommendation F.69 will be used unless otherwise agreed bilaterally.
C23 3.1.5 Normal telex procedure should be forwarded once the connection between
the subscriber of the international telex service and the mobile service and the mobile
station has been established.
3.2 Single-operator operation (direct access by a calling telex subscriber to a
foreign land station)
3.2.1 Booking
C24 3.2.1.1 If automatic operation (C19) is not possible and where an ROA allows its
subscribers to book a call directly with a land station in another country, the
originating telex subscriber should select the desired foreign land station, when
known, using automatic procedures and submit the call details to the land station
operator.
C25 3.2.1.2 The charges fixed by the land station operator should be levied on the calling
subscriber through international accounting.
C26 3.2.1.3 In addition to the information in C4, the calling subscriber should designate
the originating national telex network.
C27 3.2.1.4 As an alternative to C25 and C26, a land station may accept direct calls from
foreign subscribers in other countries provided that the calling telex subscriber
supplies the name and address of a party in the country in which the land station is
located who will take responsibility for the payment of charges.
C28 3.2.1.5 The procedures described in C25 and C27 may only be applied when an
appropriate bilateral agreement exists between the two ROAs concerned. If such an
agreement does not exist, the land station should refuse such calls to avoid accounting
difficulties.
C29 3.2.1.6 In C24 and C27 above, the call to the foreign land station will be charged as
an ordinary international telex call for its entire duration, regardless of whether it
merely serves the purpose of booking the radiotelex call or whether the land station
can extend the connection to the mobile station without having to recall the originating
subscriber.
Part E – ITU-T Rec. F.110 529
3.2.2 Setting-up
C30 3.2.2.1 When the connection to the destination mobile station can be immediately
established, the originating telex subscriber should be released by the land station.
When appropriate, the land station operator should recall the originating telex
subscriber using automatic procedures. In this particular case, the country in which the
land station is located is to be considered as the outgoing country for the call.
C31 3.2.2.2 In case C30, the land station should include in the maritime bill:
a) the landline charge;
b) the land station charge.
C32 3.2.2.3 When the connection to the destination mobile station can be immediately
established, the maritime bill made out by the land station operator should include
only the land station charge.
C33 3.2.2.4 All information regarding collection of charges for single-operator calls (see
C15) should be submitted by the land station ROA on a regular basis to be determined
by the ROAs involved.
C34 3.2.2.5 The methods to be used in collecting the charges are described in
Recommendation D.90.
3.3 Semi-automatic operation (access by a calling subscriber to one’s
international centre for the establishment of a direct connection)
C35 3.3.1 If fully automatic (C19) or single-operator (C24) procedures are not
possible, the telex operator of the outgoing international centre should receive the
booking and selects the mobile station directly. The procedures of Recommendation
F.60 should be applied.
3.4 Manual operation
3.4.1 Booking
C36 3.4.1.1 If fully automatic (C19), single-operator (C24) or semi-automatic (C35)
procedures are not available, the originating telex subscriber should make his booking
at the international telex centre of the outgoing country or network.
C37 3.4.1.2 Where conditions permit, the international telex position should select
directly the appropriate foreign land station. Alternatively, the international telex
position of the outgoing country or network should contact the international telex
position in the country or network in which the desired land station is located for the
necessary assistance to obtain contact with the land station.
3.4.2 Setting-up
C38 3.4.2.1 The land station operator will establish a connection with the originating
telex subscriber either directly or with the assistance of the own international telex
position in the country of the land station.
530 Maritime Manual
C39 3.4.2.2 Within 24 hours of the call’s termination, the land station shall pass the
following information to the international telex position of the origin country, where it
is recorded for charging and accounting purposes:
a) the calling subscriber’s telex number;
b) the mobile station’s call sign/ship station identity;
c) the chargeable duration of the call;
d) the land station charge to be collected.
3.5 Store-and-forward
C39A 3.5.1 The originating telex subscriber should select the appropriate land station
and deposit the message using the procedures desired in Recommendations F.72 and
U.80.
4 Traffic exchanged between mobile stations
C39B 4.1 Provisions from C13 to C39A apply to traffic exchanged between mobile stations.
5 Radiomaritime telex letter
5.1 Definition
C40 5.1.1 Radiomaritime telex letter: A message sent by radiotelex direct from a
mobile station to a selected land station or to a selected public telegraph office for
delivery by mail or any other appropriate means.
5.2 Operational procedures
C41 5.2.1 The mobile station should select the access code allocated for the
radiomaritime telex letter service, or the access code allocated for the fully automatic
telex service followed, if appropriate, by the telex number of the selected land station
telegraph office.
C42 5.2.2 The mobile station should supply the following information:
a) international telex number of the mobile station or mobile station number (as
provided in Recommendation F.125);
b) the Accounting Authority Identification Code (AAIC);
c) destination name and address;
d) the words “RADIOMARITIME TELEX LETTER”.
Part E – ITU-T Rec. F.110 531
DIVISION D – RADIOTELEPHONE
1 General
1.1 Language to be used
D1 1.1.1 Where applicable and where language difficulties exist, the abbreviations
and signals in related provisions of Radio Regulations [3] should be used in
radiotelephone communications between land stations and mobile stations.
1.2 Priority
D2 1.2.1 Apart from the general order of priority shown in A15 to A27,
radiotelephone calls shall have precedence in the terrestrial network, so far as possible,
over other telephone calls of the same class.
1.3 Routing of calls
D3 1.3.1 A radiotelephone call, originating in or destined to a mobile station, should
be set up via the land station that is considered to be the most suitable in relation to the
mobile station concerned in terms of the coverage and of the land station and radio
condition.
D4 1.3.2 For radiotelephone calls in the direction from land station to mobile station,
the caller should give the one approximate geographical position if possible and may
also indicate the land station to be used unless the ROA has established a specific
route to be followed. Such requests should be respected as far as is practicable.
D5 1.3.3 For radiotelephone calls in the direction from mobile station to land station,
the mobile station may call a land station it desires to use. This land station shall either
handle the call itself or advise the mobile station to use another land station that is
more suitable.
1.4 Information to be supplied, as necessary, by the calling party
D6 1.4.1 Calls from a telephone subscriber to a mobile station:
a) complete telephone number of the calling subscriber;
b) appropriate identification of the mobile station;
c) name of the land station to be used or the approximate geographical position of
the destination mobile station;
d) name of the called party, if applicable. All calls to mobile stations in the maritime
mobile service are treated as personal calls, with the possible exception of the
maritime mobile-satellite service;
e) priority when specifically requested.
532 Maritime Manual
D7 1.4.2 Call from a mobile station to a telephone subscriber:
a) appropriate identification of the mobile station;
b) the Accounting Authority Identification Code (AAIC) in accordance with
Recommendation D.90 in the single-operator or manual operation;
c) the information specified in Article 63 of the Instructions for the International Telephone Service;
d) priority when specifically requested.
D7A 1.4.3 D6 and D7 above apply to mobile station-to-mobile station calls as
appropriate.
1.5 Call duration
D8 1.5.1 The chargeable duration of a call shall be fixed at the end of the call:
a) by the controlling operator for a call originating from a mobile station;
b) for a call originating in the terrestrial telephone network;
– by the land station operator in manual or single-operator operation;
– by the operator of the international position of the outgoing country in the
semi-automatic operation.
D9 1.5.2 For a call originating from a mobile station where two land stations
participate in the handling of the call, decision of the controlling operator that has
accepted the call from the originating mobile station shall prevail.
D10 1.5.3 Should service difficulties be experienced in the course of a call, the
chargeable duration shall be reduced automatically or manually to the total time during
which transmission conditions were satisfactory, taking into account ITU-T
Recommendations.
1.6 Validity of requests
D11 1.6.1 If not cancelled by the caller or refused by the called party, requests for calls
from land to mobile stations:
a) in the VHF and MF bands shall remain valid until 0800 local time on the day
following the day on which the request was made;
b) in the HF band shall remain valid until 0800 local time on the second day
following the day on which the request was made.
D12 1.6.2 However, if it becomes obvious that the required mobile station is outside
the coverage area of the land station, the caller shall be informed as soon as possible in
order to have the call cancelled.
D13 1.6.3 All requests for calls from mobile to land stations shall be cancelled where
the call is not immediately attended to or on completion of the successive attempts
provided for by the rules of each ROA, unless there has been an express request to the
Part E – ITU-T Rec. F.110 533
contrary by the calling mobile station, which shall be able to determine the waiting
period for listening in on the land station frequency with a view to making a further
attempt to set up the call.
1.7 Exchange of radiotelegrams by radiotelephony
D14 1.7.1 Stations of the maritime mobile service that are equipped for radiotelephony
may transmit and receive radiotelegrams by means of radiotelephony. Stations of the
maritime mobile-satellite service should normally transmit and receive radiotelegrams
by means of radiotelex only.
2 Traffic from mobile stations to telephone subscribers
2.1 Automatic operation
D15 2.1.1 Whenever possible, fully automatic procedures should be used.
D16 2.1.2 For a call originating from a mobile station and after connection with the
desired land station has been established, the mobile station should forward the
appropriate telephone country code (Recommendation E.164) and the number of the
subscriber of an ROA’s telephone network. The selection procedures for calls in the
maritime mobile-satellite service, see clause 4 of Division D.
2.2 Single-operator operation
D17 2.2.1 The land station operator should select the called subscriber directly via the
automatic telephone networks if automatic procedures (D15) are not possible.
2.3 Semi-automatic operation
D18 2.3.1 The called telephone subscriber should be automatically selected by a
telephone operator in the country in which land station is situated if fully automatic
(D15) or single-operator (D17) procedures cannot be applied.
2.4 Manual operation
D19 2.4.1 The land station operator should apply manual procedures if fully automatic
(D15), single-operator (D17) or semi-automatic (D18) procedures are not possible.
2.5 Operational procedures
D20 2.5.1 The fully automatic, semi-automatic and manual procedures for the
terrestrial telephone network, as laid down in Recommendations E.105 and E.140 and
the Instructions for the International Telephone Service [6] should be taken into
account.
534 Maritime Manual
3 Traffic from telephone subscribers to mobile stations
3.1 Fully automatic operation
D21 3.1.1 Whenever possible, fully automatic procedures should be used.
D22 3.1.2 The subscriber of an ROA’s telephone network should select the appropriate
international telephone number, which would include the mobile station number. The
call routing will be determined by the appropriate country code which is chosen and
which will form part of the international telephone number (see D41). The call will
then be routed through an appropriate land station to the destination mobile station.
The selection procedures for calls from a subscriber of the international telephone
service are described in clause 5 of Division D.
D23 3.1.3 If the calling subscriber, for some technical reason, cannot use fully
automatic procedures to establish contact with mobile station, semi-automatic or single
operator procedures should be used.
3.2 Single-operator operation (direct access by a calling subscriber to a
foreign land station)
3.2.1 Booking
D24 3.2.1.1 If fully automatic operation is not possible and where an appropriate
bilateral agreement between ROA’s allows its subscriber to book a call directly with a
land station in another country, the calling telephone subscriber should select desired
foreign land station, where known, using automatic procedures and submit the call
details to the land station operator. If such an agreement does not exist, the land station
should refuse such calls to avoid accounting difficulties.
D25 3.2.1.2 The charges fixed by the land station operator should be levied on the calling
subscriber through international accounting.
D26 3.2.1.3 In addition to the information in D6, the calling subscriber must designate
his country and national telephone number.
D27 3.2.1.4 As an alternative to D25, land stations may accept direct calls from
telephone subscribers in other countries provided that the calling telephone subscriber
supplies the name and address of a party in the country, in which the land station is
located, who will take responsibility for the payment of charges.
D28 3.2.1.5 The procedures described in D25 and D27 may only be applied when an
appropriate bilateral agreement exists between the two ROAs concerned.
D29 3.2.1.6 D24 and D27 above, the call to the foreign land station will be charged as an
ordinary international telephone call for its entire duration, regardless of whether it
merely serves the purpose of booking the radiotelephone call or whether the land
station can extend the connection to the mobile station without having to recall the
originating subscriber.
Part E – ITU-T Rec. F.110 535
3.2.2 Setting-up
D30 3.2.2.1 When demand operation cannot be used, the calling telephone subscriber
will be disconnected by the land station. When the land station operator then recalls
the caller using automatic direct selection, the land station country is considered as the
outgoing country for the call.
D31 3.2.2.2 In case D30, the land station includes in the maritime bill:
a) the land-line charge;
b) the land station charge.
D32 3.2.2.3 When demand operation has been used, the maritime bill made out by land
station operator includes only:
– the land station charge.
D33 3.2.2.4 All information regarding collection of charges for single-operator calls (see
D17) should be submitted by the land station ROA on a regular basis to be determined
by the ROAs involved.
D34 3.2.2.5 The methods to be used in collecting the charges are described in
Recommendation D.90.
3.3 Semi-automatic procedure (access by a calling subscriber to one’s
international centre for the establishment of a direct connection)
D35 3.3.1 If automatic (D21) or single-operator (D24) procedures are not possible, the
telephone operator of the international centre of the outgoing country receives the
booking and selects the mobile station directly. Normal international semi-automatic
telephone procedures shall be applied.
3.4 Manual operation
3.4.1 Booking
D36 3.4.1.1 If automatic (D21), single-operator (D24) or semi-automatic (D35)
procedures cannot be applied, the subscriber should make his booking at an
international centre in the outgoing country.
D37 3.4.1.2 If conditions permit, an international position should select the foreign land
station in question directly. Otherwise an international position in the land station
country should be selected to give the necessary assistance to obtain contact with the
land station in question. Alternatively, the international telephone position of the
outgoing country or network should contact the international telephone position in the
country of network in which the desired land station is located for the necessary
assistance to obtain contact with the land station.
536 Maritime Manual
3.4.2 Setting-up
D38 3.4.2.1 The land station operator will establish a connection with the originating
telephone subscriber either directly or with the assistance of his own international
telephone position.
D39 3.4.2.2 After the termination of the call, the land station shall pass the following
information to the international telephone position of the country of origin, where it is
recorded for charging and accounting purposes:
a) the calling subscriber’s telephone number;
b) the mobile station’s name and/or appropriate identification;
c) the chargeable duration of the call;
d) the land station charge to be collected.
D40 3.4.2.3 Alternatively all information regarding collection of charges should be
submitted to the caller’s ROA on a regular basis to be determined by the ROAs
involved.
DIVISION E – RADIOTELEXOGRAM
1 General
1.1 Definition
E1 1.1.1 A radiotelexogram is a message sent by telex or telefax direct from an
originator subscriber to a foreign land station for transmission to a mobile station or a
message sent from a mobile station to a land station for transmission directly to a
telefax or telex subscriber (see Note in E5).
1.2 Provision of service
E2 1.2.1 Operating, charging and accounting procedures should be subject to a
bilateral agreement between the ROAs concerned. If such an agreement does not exist,
the land station should refuse such radiotelexograms in the shore-to-ship direction.
E3 1.2.2 Alternatively, land stations may accept radiotelexograms from foreign
originators provided that the calling subscriber supplies the name and address of a
party in the land station country that will take responsibility for the payment of
charges.
1.3 Validity of requests
E4 1.3.1 If it becomes obvious that the required mobile station is outside the coverage
area of the land station, the originator shall be informed as soon as possible in order to
have the radiotelexogram cancelled.
Part E – ITU-T Rec. F.110 537
2 Operational procedures
E5 2.1 The transmission of radiotelexograms should be in accordance with
Divisions B and C or other ITU-T Recommendations as appropriate except as
specified below or where varied through bilateral agreement.
NOTE – A radiotelexogram is different from a radiotelex or telefax call. In particular, a radiotelexogram is normally transmitted between the mobile station and the land station as a radiotelegram by Morse telegraphy or by radiotelephony.
E6 2.2 Information to be supplied to the land station, as necessary, by the
originator.
E7 2.2.1 Radiotelexogram to a mobile station:
a) international telex number and/or answer-back code or the telefax number of the
calling subscriber;
b) the date and time of origin;
c) the word RADIOTELEXOGRAM;
d) name or designation of the addressee with supplementary particulars if necessary;
e) the name of the mobile station followed, when necessary, by its call sign/ship
station identity or where this is not known, the particulars of the passage made by
the mobile station;
f) any specific delivery instructions.
E8 2.2.2 Radiotelexogram from a mobile station:
a) name and/or call sign/ship station identity of the mobile station;
b) identification of the accounting authority;
c) the date and time of origin;
d) the word RADIOTELEXOGRAM;
e) destination country and/or network;
f) called subscriber’s telex number and answer-back code or telefax number.
Bibliography
[1] International Telecommunication Regulations, ITU, Geneva, 1992.
[2] International Telecommunication Constitutions, ITU, Geneva, 1992.
[3] Radio Regulations, ITU, Geneva, 1994.
[4] List of Coast Stations, ITU, Geneva, 1993.
[5] List of Ship Stations, ITU, Geneva, 1995.
[6] Instructions for the International telephone service, ITU, Geneva, 1993.
538 Maritime Manual
ITU-T Recommendation F.120
SHIP STATION IDENTIFICATION FOR VHF/UHF AND
MARITIME MOBILE-SATELLITE SERVICES
1 Introduction
1.1 The purpose of this Recommendation is to specify a method by which an internationally
unique ship station identification may be assigned to all the ships participating in the Maritime
Mobile Services.
1.2 Terminology
The following terms are used in this Recommendation:
1.2.1 Maritime Mobile (Terrestrial) Service
F: service mobile maritime (de Terre)
S: servicio móvil marítimo (terrenal)
Conventional Maritime Mobile Services such as the HF Maritime Service, the MF
Maritime Service and the VHF Maritime Service (as defined in the Radio Regulations [1]).
Maritime Mobile-Satellite Service
F: service mobile maritime par satellite
S: servicio móvil marítimo por satélite
As defined in the Radio Regulations [1].
1.2.2 coast station
F: station côtière
S: estación costera
A land station in the Maritime Mobile Service.
Part E – ITU-T Rec. F.120 539
coast earth station
F: station terrienne côtière
S: estación terrena costera
An earth station in the Fixed-Satellite Service or, in some cases, in the Maritime Mobile-
Satellite Service, located at a specified fixed point on land to provide a feeder link for the
Maritime Mobile-Satellite Service.
Note – In this Recommendation the term coast station is also intended to include, for
simplicity, coast earth station.
1.2.3 ship station identity
F: identité de la station de navire
S: identidad de estación de barco
The ship’s identification X1, X2 … Xk identifying the ship uniquely. The ship station
identity may be transmitted on the radio path.
ship station number
F: numéro de station de navire
S: número de estación de barco
The number that identifies a ship for access from a public network and forms part of the
international number to be dialled or keyed by a public network subscriber.
Note 1 – The formats of the ship station number are defined in other E and F Series
Recommendations:
− Recommendation E.215 for telephone and ISDN numbering in the Maritime
Mobile-Satellite Service;
− Recommendation F.125 for telex numbering in the Maritime Mobile-Satellite
Service;
− numbering plans for maritime mobile (terrestrial) systems are for further study.
Note 2 – In this Recommendation the term ship station is intended to also include, for
simplicity, ship earth station.
540 Maritime Manual
1.2.4 coast station identity
F: identité de la station côtière
S: identidad de estación costera
The coast station identification X1, X2 … Xk transmitted on the radio path.
Note – In this Recommendation the term coast station identity is intended to also
include. for simplicity, coast earth station identity.
1.3 Basic considerations
The considerations that form the basis of this ship station identification system are:
a) that every ship shall have a unique ship station identity;
b) that the same unique ship station identity should be used in both VHF/UHF and
Maritime Mobile-Satellite Systems;
c) that the same unique ship station identity should be used for all telecommunication
services;
d) that it is desirable that the ship station number and the ship station identity are
related in a simple and unambiguous manner;
e) that the capacity of the ship station identification system shall be sufficient to admit
all ships wanting, or required, to participate in the various Maritime Mobile Services
at present and in the foreseeable future;
f) that the ship identity system shall be a numerical system, and should use the full
range of decimal digits;
g) that two or three of the digits, X1X2X3, of the ship station identity shall indicate the
ship's nationality.
2 Ship station identification
Ship station identity is established as nine digits.
X1X2X3X4X5X6X7X8X9
The initial three digits define the nationality of the ship as indicated in the following
sections.
Since the whole or a part of the ship station identity is used in the ship station number,
certain restrictions may be imposed on the allocation of ship station identities for the Maritime
Mobile-Satellite Service. Such restrictions are identified in Recommendations E.215 and F.125.
The use of the ship station identity in maritime mobile (terrestrial) systems is for further study.
Part E – ITU-T Rec. F.120 541
3 Assignment of ship station identification
3.1 Assignment of blocks of numbers
Blocks of numbers should be assigned to countries so that individual Administrations
may systematically assign ship station identities within those blocks.
3.2 Identification of ship’s geographical region
The first digit of each ship station identity is intended to identify the geographical region
to which the nationality (registry) of the ship relates. Only the digits 2 through 7 are used for this
purpose to identify easily the world's regions as follows:
2 – Europe
3 – North America
4 – Asia (except Southeast Asia)
5 – Oceania and Southeast Asia
6 – Africa
7 – South America.
Arrangements may therefore be made to systematically assign a ship station identity to
each ship as soon as national blocks are allocated. The digits zero (0), one (1), eight (8) and nine
(9) are allocated for other purposes as indicated below.
The digits eight (8) and nine (9) are not used for identification of geographical regions.
However, for maritime VHF/UHF systems, the digits 8 and 9 may be used to expand network
access as shown in § 8.2. The allocation of the first digit of the ship station identity is
summarized in Table 1/F.120.
TABLE 1/F.120
Allocations of first digit (X1) in the ship station identity
First digit (X1) of ship station identity Use
0 Group call/coast station identity
1 Reserved for future expansion
2 Europe
3 North America
4 Asia (except Southeast Asia)
5 Oceania and Southeast Asia
6 Africa
7 South America
8 See § 8.2
9 See § 8.2
542 Maritime Manual
3.3 Identification of ship’s nationality
Since blocks of the ship station identities would be systematically assigned by country, a
ship’s nationality can be determined by analysing the first three digits of its ship station identity.
The digits to be analysed are called Maritime Identification Digits (MID). Examples of
the maritime identification digits for ships are given in Table 2/F.120.
TABLE 2/F.120
4 Assignment of maritime identification digits
Each MID represents a discrete capacity assigned according to a plan that relates
assigned capacity to ship population. A plan has been developed by the World Administrative
Radio Conference for the Mobile Services (MOB-83) [2] and is contained in Appendix 43 to the
Radio Regulations [1]. The Radio Regulations make provision for the allocation of additional
MIDs for a specific country when necessary.
5 Group calls
X1 = 0, X2 = 1 to 9 and X1 = 0, X2 = 0, X3 = 0, X4 = 0 to 9 are assigned to indicate a
group call to a group of ships having a community of interest. Such calls may be barred in the
public switched network and/or at the coast stations. Control of group calls may also be achieved
by the use of special group service access to the coast stations. The group call numbering
scheme used in the INMARSAT system is given in Annex B to Recommendation E.215 and in
Annex B to Recommendation F.125.
Country Maritime identifications
digits (MID)
Ship station identity
P 231 from 231 000 000
to 231 999 999
Q 233, 234 from 233 000 000
to 234 999 999
R 236, 237, 238 from 236 000 000
to 238 999 999
S 240 to 249 from 240 000 000
to 249 999 999
Part E – ITU-T Rec. F.120 543
6 Coast station identity
X1 = 0, X2 = 0, X3 = 1 to 9 are assigned to indicate coast station identities in maritime
mobile (terrestrial) systems.
7 Future expansion of the ship station identification system
X1 = 1 as in the format 1 XXXXXXXX has been reserved for future expansion.
Note – X1 = 1 is used in the INMARSAT standard A system for identification of ship
earth stations (see Recommendations F.125 and E.215).
8 Considerations related to ship station identity assignment
8.1 The ship station identity, or part of it, will be included in the INMARSAT mobile
number. The way in which this is done for INMARSAT mobile numbers is described in
Recommendations E.215 and F.125.
The relationship between the nine-digit ship station identity and the part of it which is
used in the ship station number is illustrated in Table 3/F.120. If the part of the identity used in
the number is shorter than nine digits, then the corresponding identity is obtained by adding
trailing zeros to form nine-digit ship station identities. This principle must be observed when
allocating ship station identities for ships in the Maritime Mobile-Satellite Service (see
Recommendations E.215 and F.125).
TABLE 3/F.120
8.2 Numbering plans for the maritime mobile (terrestrial) services are for further study. The
principle of § 8.1 is likely to apply for these services also.
Part of ship station identity
used in ship station number
Digits on the
automatic network
Ship stations identity Digits in the ship
station identity
MID X4X5X6 6 MID X4X5X6 000 9
MID X4X5X6X7 7 MID X4 X5X6X7 00 9
MID X4X5X6X7X8 8 MID X4X5X6X7X8 0 9
MID X4X5X6X7X8X9 9 MID X4X5X6X7X8X9 9
544 Maritime Manual
For maritime mobile (terrestrial) services, additional ship station numbering techniques
may be used to expand network access to more ship stations on a regional and national basis as
follows:
Ship station number
(or part thereof)
Ship station identity
8Y X4X5X6X7 MyIyDy X4X5X6X7 00
9 X4X5X6X7X8 MnInDn X4X5X6X7X8 0
In this arrangement, the digits 8Y may be 80 to 89 to define as many as ten foreign
MIDs (shown as MyIyDy) to permit automatic calling of ships of particular nationalities. The
coast station would be required to translate a given 8Y to a particular foreign MID. The digit 9
may be used to indicate the maritime identification digits for ships of the same nationality as the
network and the coast station. The coast station would be required to translate 9 to one particular
national MID (shown as MnInDn).
References
[1] Radio Regulations, ITU, Geneva, 1982, revised in 1985, 1986 and 1988.
[2] Final Acts of the World Administrative Radio Conference for the Mobile Services(MOB-83), ITU, Geneva, 1983.
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