al plus_alc plus overwiew

AL plus and ALC plus Copyright Siae Microelettronica S.p.a.1

AL plusALC plus

PDH radio

Instructor : Monthien Satantoranin

SIAE Microelettronica South East Asia & Pacific


Training itemsTraining items1. AL plus2. SCT3. LCT4. AL Plus Ethernet5. ALC Plus6. ALC Plus Ethernet7. AL Troubleshooting: alarms and loops8. Propagation: one easy example of hop calculation


PDH AL plus: hardware and circuitry

1


Line Interface Module: Up to 32xE1, 4x10/100 BaseT + 24E1

Main Controller (Service channels, LCT connection, Alarms IN/OUT)

Radio Interface Module 1 and 2 (Cable Interface + Power Supply)

IDU AL plusIDU AL plus


IDU AL plus 1RU IDU AL plus 1RU AL Plus 1+1 32xE1

Equipment Controller

LIMRIM 1A

RIM 2A

AL Plus 24E1 +4xEth


IDU AL plus 2RUIDU AL plus 2RU

AL Plus 1+1 53xE1

AL Plus 2x(1+1) Matrix Stm1


ALC PlusALC Plus

ALC Plus EthernetALC Plus Ethernet


ODUODU

Unprotected ODU

1+1 ODU


ODU with separated antenna

1+0 pole mounting

waveguide flange

antenna


ODU with separated antenna

1+1 wall mounting

waveguide flange


1+1 hot stand-by= FHIGH

= FLOW

= Stand-by= Active

Both radios, working at the same frequency, are active in Rx but only one is active in Tx:

1 antenna – Branching losses are inserted in link budget

2 antennas –Link is in space diversity (and without branching losses)

Best performance for d=150 (d=distance between antennas)

ODU ODU

ODU ODU

IDUIDU

1 1

2 2


1+1 frequency diversityODU ODU

ODU ODU

IDUIDU

1 1

2 2

All radios, working at different frequencies, are active in Rx and Tx

1 antenna – Branching losses are inserted in link budget

2 antennas –Link is in space diversity (and without branching losses)

= F1HIGH

= F1LOW

= F2HIGH

= F2LOW


Software Keys

Following functionalities are enabled through a software key:

• Capacity changing

• Modulation changing

• Way side traffic

• OSPF Option

• Fade Margin Test Option

• Ethernet


AL plus : main facilitiesAL plus : main facilitiesNodal versionPRBS generatorATPCAdaptive modulationBase 5 hierarchy Fade margin


Available versionAvailable versionNew pdh AL is available in many versionsConfiguration can be set via software : Modulation: 4QAM, 16QAM, 32 QAM Capacity: 2, 4, 8,16,32xE1, 5, 10, 21xE1 (1RU)

42xE1, 53xE1 (2RU)4xLAN+24xE1

Configuration: 1+0, 1+1 h.s.by or eterofreq.

IDU is frequency, capacity and modulation independentIDU is frequency, capacity and modulation independentODU depends by frequency onlyODU depends by frequency only


Modulation

User InterfacesCapacity [Mbit/s]

4 QAM 16 QAM 32 QAM

- 2xE1/4xE1/16xE1

- 10/100BaseT + NxE1

41016203242

- 32xE1

- 10/100BaseT + NxE1

6484

-10/100BaseT + NxE1-53xE1

100106

User interfacesUser interfaces


Equipment structureEquipment structure


ControllerController


LIM LIM Tx directionTx direction


LIM LIM Rx directionRx direction

FEC *

(block code)

errors

*FEC = Forward Error Corrector

Example: Without BER=10-6

With BER=10-13 (+2.5 dB)


RIMRIM

140 MHz


ODUODU


ATPC ATPC (Automatic Tx Power Control)(Automatic Tx Power Control)

40 dB

ATPC range


Characteristics : examples(1)Characteristics : examples(1) Tx power (4QAM/16QAM/32QAM) in dBm : 4 GHz +29 / +24 / +22 7 GHz +27 / +22 / +20 15 GHz +25 / +20 / +20

18 GHz +20 / +15 / +15 23 GHz +20 / +15 / +15 Tx/Rx spacing in MHz: 4 GHz 100 7 GHz 154/161/168/196/245

15 GHz 315/322/420/490/72818 GHz 1010

23 GHz 1008/1200/1232/ Power consumption in W (for frequencies > 15GHz): 1+0 < 32 1+1 < 55

4x(1+0) < 106


Characteristics :examples (2)Characteristics :examples (2) Rx 10-6 thresholds (4QAM/16QAM) guaranteed, dBm: - in 21x2 4 GHz -81.5 / -77.5 7 GHz -80.5 / -76.5 15 GHz -80 / -76

18 GHz -79.5 / -75.523 GHz -79.5 / -75.5

- in 4x2 4 GHz -89 / -85 7 GHz -88 / -84 15 GHz -87.5 / -83.5

18 GHz -87 / -83 23 GHz -87 / -83

Max Rx power - 20 dBm


Setup with SCT/LCTSetup with SCT/LCT

1. Set modulation and capacity2. “Dynamic/adapt. Modulation” disabled3. “Tx Switch on remote alarm” disabled4. Set the same Link Id on local and remote 5. Enable the same tributaries on local and remote 6. Select the same RF Channel on local and remote7. Set Tx power at Max value, Tx power control manual8. Check antenna aiming on local and on remote


Setup with SCT/LCT (2)Setup with SCT/LCT (2)1. Set Lan IP Ethernet port address and netmask2. Set the Agent (copy Ethernet port address)3. Set all the other ports as Unnumbered, press:

4. Do the same on remote side5. Into Subnetwork configuration wizard add station and

local and remote Agents, select Send

Set values Store Restart


IDU AL plusIDU AL plus

IDU-ODUcable connector :

SMA type

E1 way side (only for 16E1

and 32E1)

Service channelsconnectors : RJ 45 type

Alarms LEDs : IDU ODU REM TEST

Processor FAIL alarm LED

75/120 ohm E1 connectors: SCSI type

LAN Connectors: RJ 45 type Duplex and Activity on LAN interfaces


ODU installation (1)ODU installation (1)

REF.


Frequency signals:Tx IF 330 MHzRx IF 140 MHzTelemetry IDUODU 17.5 MHzTelemetry ODU IDU 5.2 MHz

Max length (1/4 inch cable)Maximum distance between IDU-ODU 370 mRequired Cable Return Loss: Better than 22 dB from

100 MHz to 400 MHz

Interconnection cable


Switch modes Auto Preferential: operator can select which branch must be

operative without alarms. Wait Time = time before coming back to the preferential

branch when alarms disappear. In this way the controller doesn’t switch continuously in case of fleeting alarms.

Reset = Wait Time is not respected Full auto: both branches have same priority

Manual forcing Operator can select which branch must be operative

despite alarms


Tx switch criteria1. RIM PSU alarm2. Manual forcing3. Cable short/ Cable open alarm Modulator failure ODU unit failure alarm VCO failure alarm IF unit alarm

ODU PSU alarm Tx power low alarm4. Rx failure on both remote radios 5. Revertive Tx

Highest priority

lowest priority


Rx switch criteria1. RIM PSU alarm2. Manual forcing3. Cable short/open alarm

Base band unit failure alarm Demodulator failure ODU unit failure alarm VCO failure alarm IF unit alarm

ODU PSU alarm High BER alarm (selectable: BER>10-3,-4,-5)4. Low BER alarm (selectable: BER >10-6,-7,-8) 5. Early warning alarm (selectable: BER >10-9,-10,-11,-12) 6. RF input low (selectable from -40dBm to -99dBm)7. CRC pulse8. Revertive Rx

Highest priority

lowest priority


Management LAN into a StationVery easy Cabling of Local Station LAN : Integrated miniswitch on equipment No need of an HUB (difficult to power supply) 2 LAN ports functionally equivalent No need of crossed cables (auto detect)


EQUIPMENT FEATURE MANAGEMENT


Configuration upload/downloadUpload (from equipment)From Tool menu, open the proper TemplateSelect Upload operation and the equipment you want to upload information fromSave them in a file (*.cfg)

Download (to equipment)From Tool menu, open the proper file (*.cfg)Select Download operation and the equipment you want to download information to

Uploaded parameters and *.cfg file are editable using

Equipment Configuration Wizard.


Configuration TemplateConfiguration template: it is relevant to equipment radio parameters as frequency, attenuation, capacity, thresholds,…

Address configuration template: it is relevant to management parameters as port IP addresses, routing tables, remote elements tables, OSPF.

Both configurations are necessary during first installation or when Controller module is substituted with a spare one: you can use a file to download or set every parameter manually.


Full backup

The whole amount of parameters (equipment parameters, address parameters and remote element table) can be uploaded from equipment, saved in a file (*.bku), downloaded to equipment.

These parameters cannot be editated.


LCT:

AL plus

3


Configurator AL plus


LCT: AL plus nodal


AL plus nodal: ConfiguratorAL plus nodal: Configurator

A button to show the other two radios


Line-up: Radio parameters

These parameters can be set locally only… all changes must be performed first on remote …and after on the local equipment

Radio parameters to have the traffic working are:

1. RF channel

2. Modulation

3. Capacity

4. Link ID


Modulation/Capacity

Capacities for selected modulation


Configuration parameters

Link ID 0 not usedLink ID 0 enable

LinkIDLOC LinkIDREM (always)

After Controller unit replacement, the configuration mismatch (Application alarm on) can be solved in the following way:

1) download the old configuration file: old setup is downloaded on the controller

2) push Apply Configuration button: old setup is downloaded on the equipment


Adaptive modulation During bad propagation periods the system changes modulation to increase system gain keeping constant the transmitted bandwidth and reducing transmitted capacity, increasing system availability (for priviledged traffic)

Modulation has been varied and capacity has been reduced

Below this PRx threshold, remote PTx increases (as ATPC feedback) when in reduced modulation. This offset is the number of dB from PRx @10-9. Default 2dB

Tx power increase of 3db if 16QAM. Enable only if permitted by rules in your country.

PTx power increase , amount of additional output power with reduced modulation. Default 5dB

ATPC hysteresis in dB for 16QAM recovery. Default 0dB

Seconds of stable PRx before recover to 16QAM. Default 10sec

Changes can be done only with Adap. Mod disabled

Adaptive mod. Enabling


Adaptive modulationWhen happens?

Request of modulation change from 32/16QAM to 4QAM if, at worst receiver (B):

1. PTx(AtoB) = PTx | MAX (ATPC on, and Tx at max value)

2. PRx(B) is lower than ATPC Low Thresholds (Remote needs more power)

3. BER at (B) receiver lower than 10-9

Recovery of modulation from 4QAM to 16/32QAM if, at both ends:

1. PTx at 4QAM = MAX possible for 16/32QAM

2. ATPC not requiring remote TX power increase

3. BER no errors in the last seconds (default 10 sec)


Adaptive modulation

If PTx Max|4QAM=20dBm and PTx Max|16QAM =15dBm, difference is 5 dB so

PTx boost can be 0÷5dB

If ATPC value are not correct Dyn/adaptive modulation is not activated

Adap. Mod now active and with reduced Mod

Warning : No configuration change must be done with SCT/LCT when Dyn/Adaptive Modulation is activated ! If you need a loop or any other change please first deactivate Dyn./A.M.


Adaptive modulation: half traffic is preserved

16/32QAM capacity 4QAM capacity- 4x2 @16QAM, 5x2 @16QAM no adaptive mod.

- 8x2 @16QAM 4x2 @4QAM

- 10x2 @16QAM 5x2 @4QAM

- 16x2 @16QAM 8x2 @4QAM

- 21x2 @16QAM 10x2 @4QAM

- 32x2 @16QAM 16x2 @4QAM

- 42x2 @16QAM 21x2 @4QAM

- 53x2 @32QAM 21x2 @4QAM

Capacity decrease is pointed out by Reduce Capacity Alarm


What IDU PLUS offers:


Differences between AL and AL Differences between AL and AL plusplus

Out of standard capacities

Nodal configuration

Dynamic/Adaptive modulation

STM-1 input (see next slides)

Two Q3 ports


General preset:thresholds

HBer,LBer, EWL thresholds

Rx Power Low thresholds


General preset:Rx switches

1+1

1+0

In case of Hber, Lber, EWL, first CRC correction

In case of no Rx


General preset:Tx switch

If both remote radios don’t receive, on local side Tx switch is performed


General preset:Miscellaneous


Radio branch: Frequencies

RF channel must be set.

Tx frequency is in RED


ATPC threshold 10-15 dB higher than BER 10-3 threshold

Radio branch:ATPC

orManual Ptx setting


Radio branch:Settings

Traffic ok with: Carrier only = Off , Tx Transmitter = On, Rt PSU = On

On no modulator (no traffic)

Off traffic ok

On traffic ok

Off Radio receives only

On Radio works (48Vdc in the cable)

Off Cable can be disconnetted (no 48Vdc)


PRBS (Pseudo Random Bit Sequence)

Alarm on “Checked signal” lineMeasure results and duration

Tributary selection if checked is Signal 2MBit

P.R.B.S replaces the traffic on selected channelP.R.B.S. test is pointed out as Manual Operation (subject to timeout)

Checked signal selection

Measure status

Pattern type

Sync Los events during test


Fade MarginFade Margin Fade margin:Problems for executing the test


Fade margin


1) Fade margin : Remote link

Remote terminal must be declared as “Remote link”

In “equipment 2” we want to perform Fade margin measurement


2) Fade margin : summary2) Fade margin : summary

Input data : Expected F.M. (calculated by the customer directly, basing on nominal output power and nominal LBER threshold)

External Atten. : all the losses between radio and antenna (excluding Branching)

Curr. Step : four step (TxL1RxL1 , TxL2RxL2 , TxL2RxL1 , TxL1RxL2)

Real F.M. : value based on expected F.M. adjusted with real output power, real LBER threshold (and External Atten.) measured at Final Test Departiment in SIAE and stored in ODU

Real F.M.v. : value calculated decreasing Local Output power (1 dB step) until Remote LBER alarm activation. This value should be compared with declared one (Input data)


64Kbit/s

SOH Bytes structure

RSOH

MSOH


R S T mode : RSOH


A1, A2, J0

If A1 and A2 are recognised by aligner and if J0 is the correct one, RSOH bytes are extracted from SOH.

In case of: - no input (alarm is LOS) - failed recognition of A1,A2 (alarm is LOF) - J0 not correct (alarm is Path Trace Mismatch)then:

1. MS AIS signal is inserted on MSOH and on Payload

2. Local restart is enabled


B1, D1, D2, D3, E1, …

B1:Byte Interleaved parity: carries link quality info (relevant to G.826)

D1, D2, D3: DCC data communication channel for supervision and management (192 Kbit/s); DCC loss is reported by QECC alarm

E1 and 3X: bytes for EOW and low speed data channel


Nodal IDU AL plus Nodal IDU AL plus

High Speed (311 Mbps) Nodal Interconn. (up to 3 IDUs Full cross connection capability)

Single IDU: 4x(1+0) 2x(1+1) 1+0/1+1 Mixed configuration

Multiple IDUs (up to 3) 12x(1+0) 6x(1+1) 1+0/1+1 Mixed configuration

A

B

C


16E1 Add/Drop

Site A

IDU NETWORK APPLICATIONS:IDU NETWORK APPLICATIONS:STM-1 Line interface – Typical ApplicationSTM-1 Line interface – Typical Application

53E1

53E1 Add/Drop

Site B

STM-1

SDH network

Directly from E1 one side to STM1 on the other side without the need of an additional ADM and cabling


IDU NETWORKIDU NETWORK APPLICATIONS:APPLICATIONS:

STM-1 Line interface and Nodal Interfaces – Typical ApplicationSTM-1 Line interface and Nodal Interfaces – Typical Application

53E1

16E1 Add/Drop

Site A

Site B

Site C

53E1

SDH network

STM-1

Directly from E1 one side to STM1 on the other side without the need of an additional ADM and cabling


Nodal IDUs exampleNodal IDUs example

53E1

53E1

53E1

53E1

53E1

53E1

53E1

53E1

53E1

53E1

53E1

53E1

3xSTM-1 (1+1 MSP) + 48E1

Up to 12 radio direction (53x2 each)Up to 3xSTM-1 interfacesUp to 48E1 physical interfacesFor a total of 873E1 crossconnected into the

node (unblocking)


Nodal IDU

Node configuration: now the node is made of 3 x 2RU = 3Elems

Node A

Only D/I

Drop Insert & Nodal

- - - Terminal

Nbus ring protection on E1s


Syncronization: SETS

Synchronization Sources

Equipment clock

Source priority:

• 1Max • 2min • 4min …..• disabled

Selected: available synch. with higher priority.

Available: present and not degraded

Synch. status

White: not forced

Blue: forced

White: no alarms

Red: alarmed (drift and/or LTI)

2MHz output clock


Syncronization: SETS

Enabled selected: sync source used, with shown priority

Enabled unselected: sync source disabled , not used


Nodal IDU VC4 Settings Nodal IDU VC4 Settings

Must be defined in case of configuration change


Nodal IDU VC12 Settings Nodal IDU VC12 Settings

Must be defined in case of configuration change


Nodal IDU Cross connection Nodal IDU Cross connection


Nodal IDU Cross connection 1 Nodal IDU Cross connection 1


Nodal IDU Cross connection 2Nodal IDU Cross connection 2


Nodal IDU Cross connection 5Nodal IDU Cross connection 5Nodal configured as RadioA=RadioB= 2x(1+0)


Tributaries

Line loop

Internal (radio) loop

Line enabled

53E1= 32+21


ALCplus WEB LCTALCplus WEB LCTALC plus can be configured using a WEB Browser

in three different ways:

1) Starting from SCT

2) From the WEB browser via LAN

3) From WEBLCT console via USB

WEBLCT is very similar to standard LCT integrated with SCT Equipment menu

In order to have the whole link in one page only, local equipment is declared “managed by SCT”, remote one is declared “remote link”

AL plus and ALC plus Copyright Siae Microelettronica S.p.a.87ALCplus WEB LCTALCplus WEB LCT

This is the software to manage a single ALC plus.

All the commands are the usuals…with a different style


Equipment menu: a mix of SCT equipment menu and LCT command list


WEBLCTWEBLCT

Traffic parameters (without RF channel)

Link alarms (RF input and quality) Rx switch


E1 settings

Tributary setting: a line can work only if enabled (local and remote side)

Line loop

Internal loop


Traffic parameters: Tx power and RF channel

RF channel (and freq. in MHz)

Manual operation

Tx power


Ethernet port settings 1

Interface parameters


Ethernet port settings 2

802.1q VLAN parameters

802.1p priority parameters


AL Ethernet : 16E1 +3xEthAL Plus Ethernet 24E1+ 4xEthALC Plus Ethernet* : 32E1+3xEth

___________________________________

*ALC plus: Ethernet traffic works with not hierarchical capacity only

Ethernet IDUs: available interfaces


Ethernet switch*

MAC Address Table size

Emptying algorithm of queues: 8421 WFQ

or strictly priority

Life of info in

MAC Addr. tablePacket size

Queue assignement depending 802.1p: depending on input priority, the packet is sent to the selected queue of a port (level 2)

Queue assignement (level 3) depending on PTOS or DSCP

VLAN management

Setting of waiting time before Link Loss Forwarding (010 sec.)

*only on Ethernet LIM !

(512/1024/2048)

(1522/1536)


Queue selection

Depending on priority TOS the queue is selected.

View filter

PTOS values

(64 = 26)

DifferentialServiceCodePoint values 14 = 1 + 4x3 + 1 AF=Assured Forwording (4 classes and 3 values)

PrecedenceRoutine

Priority

Immediate

Flash

Flash override

Critic/ECP

Internet Ctrl

Network Ctrl

DelayNormal

Low

ThroughputNormal

High

ReliabilityNormal

High


VLAN map (level 2)Port 1 Port 2 Port 3 RadioPor

t

VLAN 760 doesn’t transit through port 2

760

VLAN 760 exits through port 2 untagged

VLAN 760 exits through port 2 with tag 760

VLAN 760 exits through port 2, with the same tag it has at input (unmodified)

VLAN tag given to untagged packet


VLAN management

Example of VLAN list: VLAN tag of input packet is not included, see Virtual LAN card in “LAN-x” [x = 1, 2, 3]

Not assigned


LAN settings: Interface

Cable: straight or crossed

Port status

LAN SpeedFlow control

LLF status

LAN status

In ALCplus the bitrate of each port can be set


LAN settings: Virtual LAN

Untagged frame in output:Unmodified, Tagged, Untagged

Output ports of packets in input at LAN1

Tag added to untagged frame if

output is tagged

Disable 802.1q: no Tag filter, “LAN per port” rules

Fallback: if input is tagged, Virtual LAN map rules will be followed; if input tag is not present in the map or input is untagged, Lan per port rules will be followed

Secure: if input is tagged, Virtual LAN map rules will be followed; if input tag is not present in the map or input is untagged, packets will be dropped

1


LAN settings: Priority

How to manage input priority:

-Disable (No check): forcing of default values- 802.1p (level 2)- IpToS (level 3)- First 802.1p then IpToS- First IpToS then 802.1p

default Queue and default Priority added to output if input is without priority


Local LAN1 – Remote LAN14 settings:1) LAN1Internal LOCAL

2) Internal LAN 1 LOCAL

3) Internal LAN1 REMOTE

4) LAN1 Internal REMOTE

ANYENABLED


Local LAN1 – Remote LAN1Local LAN2 – Remote LAN2Local LAN3 – Remote LAN3

SEGREGATED!

LAN1, LAN2, LAN3, Internal : Enabled“LAN per Port” : LAN1Internal, LAN2 Internal, LAN3 Internal, InternalLAN1/2/3Default Vid(local/remote): LAN1=1/6, LAN2=2/7, LAN3=3/8, Internal=4/5Ingress Filtering Check: FallBackUntagged frame Egress mode: LAN1/2/3=Untagged, Internal Port=TaggedVirtual lan map

Local

Remote


Normal operating conditionNormal operating condition

Rx level on both ODU match values given by hop calculation.

Rx level accuracy: -40 dBm -75 dBm range ± 3dB -30 dBm -40 dBm range ± 4dB


Faulty condition: alarm notificationFaulty condition: alarm notificationA faulty condition is pointed out by IDU front panel LEDs:

- FAIL: controller self test failed- IDU: alarms from LIM and/or RIM- ODU: alarms from radio transceiver - REM: any alarm from other end- TEST: manual operation active

SCT window:- Log history area (with alarm correlation)- Equipment view current alarms (with alarms grouping)


Alarms grouping : Current AlarmsAlarms grouping : Current Alarms


ALARMSThere are two directions of alarms: Tx and Rx

Tx – This line starts in LIM and arrives to output flange: when a situation of more alarms is occurring, the most significative alarm of them is at the beginning of Tx chain, all the others after are due to this

Rx – This line starts in output flange and arrives to LIM: when a situation of more alarms is occurring, the most significative alarm of them is at the beginning of Rx chain, all the others after should be caused by this

Most Significant alarmRx

Tx

RIM

LIM

ODU

LIM

RIM

ODU

4


Synthesis, Local/Remote group

Alarms are divided in groups: the name of the group is the name of the module where alarms come from, or the name of a specific characteristic of these alarms

A “Synthesis …” alarm, with the name of relevant group, is the OR of alarms of that group (AL only).

If an alarm occurs, also relevant LOCAL synthesis occurs (…while REMOTE synthesis occurs in remote equipment)


Alarms grouping : COMMON

Alarms not related to a specific part of the equipment but relevant to the link.

Example:

– EOC radio alarm (relevant SCT management)– Link telemetry fail (relevant traffic, ATPC info, man op)

If both alarms are ON, the link is interrupted. Investigation must be made on a possible condition of bad

propagation, or equipment failure


No link between Local and Remote station. Traffic is cut.

Link telemetry is inserted in main radio frame in Bit Insertion circuit inside LIM, and contains commands for the remote station: switch off the radios on remote side in case of local RF loop, Link ID, ATPC info.

Telemetry link is a connection between local and remote IDUs.

TEST - if this alarm occurs, a double IDU loop (both branches) can be done: if this alarm disappears, local IDU is OK and the problem is after (propagation, local radios, remote equipment).

Link telemetry fail


Communication Radio EOC Data link

No link between Local and Remote station or wrong port address configuration.

EOC is the channel involved in management communication.

If EOC radio link is active:

- Traffic is OK

- Management is cut (no remote)


Communication 2Mb EOC Data link

No EOC channel is present on selected tributary in selected timeslot : wrong port address configuration or no tributary input (LOS).EOC is the channel involved in management communication.

If EOC 2Mb link is active:

- Management is cut (no remote)

- If relative LOS is active, traffic on that tributary is out


PRBS FailWhen PRBS is working and no signal is received on checked signal, in PRBS window the field Sync Los Alarm is active together with PRBS Fail in Current alarms window

Every ON-OFF transitionincreases the field

PRBS Fail Alarm Counter


Revertive

When a branch is declared preferential, the switch on opposite branch gives Revertive alarm.

The return to preferential branch, when available again, happens after “Wait Time” period.


2Mb/s G.704 (Trib.x) Radio Fail/AIS and/or Line Fail/AISWhen management messages come via tributary timeslot, further checks are performed on both directions of used tributary


Tx FailTx Fail

When on remote side both radios don’t receive, on local side a Tx switch command is performed and Tx fail alarm is enabled.

When this alarm is on,check local ODU in stand by

This functionality is enabledin LCT – General PresetThe alarm remains activeuntil Reset is given


Link IDLink IDAlarm is on if Link ID check is enabled (Link ID 0) and remote Link ID is different from the local one.

Traffic is cut but signal is received and measured. Output = AIS

This alarm causes:


Alarms grouping : LIMAlarms grouping : LIM

These alarms come fromExternal fault: tributary LOSLIM failure: -Multiplexer/demultiplexer failure -Modulator/demodulator failure Warning: modulator/demodulator

circuitry is spread into LIM and RIM modules.

RIM or ODU alarms propagation (seen in LIM as Baseband RX alarm)


Tributary-1 Signal loss

Loss Of Signal alarm is active when a situation opposite to that foreseen by configuration is performed on tributary interface:

No input or

orcable disconnected

Tributary connected

TRIB. STATUS

Tx


Multiplexer fail

The alarm is given during multiplexing of input tributaries by

Overflow stuffing memories

Overflow is due to bad clock of one tributary (too fast: >+50ppm) or hardware failure

In case of Multiplexer Fail the signal forwarded to the radio is N x AIS (from all the N tributaries)

Tx


Branch-x Modulator Fail

This alarm is active when at cable interface Tx IF modulated signal (330 MHz) is missing or is under a certain value; this is due to: Modulator faulty

Cable IDU-ODU open (that produces high VSWR value)

Traffic is cut

Tx


Branch-x ODU-IDU Communication fail

This alarm occurs when on carrier used to receive information from ODU, or remote commands from other side, are detected:

CRC errors

Loss of frame

This carrier is separated from carrier used for opposite direction (IDUODU) and from TX or RX carriers


Branch-x Demodulator Fail

Traffic is cut

This alarm is active when average deviation of symbol recognition is higher of a certain level.

Every problem in constellation gives Demodulator alarm: Problem of digital conversion of received signal from RIM I or Q signal missing High level of interference (bad quality but good Rx level) No Rx IF modulated signal (140 MHz) from ODU (no Rx, ODU faulty, IDU/ODU cable open)

Demodulator alarm causes:

Rx quality alarms (HBER, LBER, EWL) Rx signal alarms (BaseBand Rx)

Rx

Branch Rx quality alarm (software settable)


Branch-x BaseBand RxThis alarm is active when

Bit Extraction does not work (in LIM)

Demodulator does not work (in LIM)

Demodulator does not receive from RIM or ODU

BaseBand Rx causes:

Demultiplexer Fail

Traffic is cut

Rx


Demultiplexer Fail

The alarm is given during demultiplexing by:

Frame Alignment Word not recognised (LOF - loss of frame)

Overflow destuffing memories

Overflow memories of hitless Rx switch

BaseBand Rx alarm

In case of Demultiplexer Fail, output is AIS (from all the tributaries)

Rx


Alarms grouping : NODE


Node (1 or 2) Signal Loss Alarm

NBUS cable, connecting different Nodal IDU of the same node, is

missing

IF IDU is a “no Nodal” unit, alarm is disabled

NBUS cable F03471*, despite RJ45 connector, is not an Ethernet cable

*Siae code


Node (1 or 2) Signal Lof Alarm

The FAW, Frame Alignement Word in the signal on NBUS

connection, has not been recognized


Node (1 or 2) MsAIS Alarm

The payload in the frames of the signal in NBUS connection does not contain the 126 E1 streams but AIS signal: a LOS or LOF alarm is present in another NBUS connection.

(Not active at the moment)


Node (1 or 2) Check Alarm

The Nodal IDUs connected through NBUS cable don’t have the same Identifier. Identifier is not modifieble by the user

Correct node setup

1 2

2

22

211

1 1

2 units node 3 units node


Alarms grouping : SETS


BaseBand Sets STM1 (T0) Drift Alarm

Drift: clock frequency is out of range


BaseBand Sets STM1 (T0) LTI Alarm

LTI: Loss of Timing Input The input the clock is extracted from, is missing


BaseBand Sets T4 Fail alarm

BaseBand Sets T0 Fail alarm

Sync input: no synchronismous source (in input) is available or without problem

Sync output: T4 synchronismous generation is not available


Alarms grouping : SNTP

(Not active at the moment)


Alarms grouping : STM1


92

STM-1 line side alarms STM-1 Los: loss of signal (no input), AIS is inserted on tributary lines (Tx). STM-1 Lof: loss of frame (failed recognition of A1,A2). Perform a STM-1 loop

and if alarm persists, replace LIM (Tx). STM-1 J0 Trace Identifier Mismatch: J0 received is not the expected one. AIS

inserted on VC12. Check configuration and network (Tx).In case of: LOS, LOF, J0 TIM

then:- MS AIS signal is inserted on MSOH and on Payload- Local restart is enabled

STM-1 B2 Signal Degraded: BER on MSOH B2 is higher than configured threshold. Check the network.

STM-1 B2 Excessive BER: HBER on MSOH B2. Check the network STM-1 MsAIS: AIS detected in input. Check the network. External fault. STM-1 MsRDI: K2 carries Remote Defect Indication in input from remote ADM.

External fault. STM-1 Qecc: ECC interrupted line side. Check radio link and IP addresses

settings.

What to do with a STM1 line side alarm:


Alarms grouping : RIM

These alarms come from External fault: demodulator fail alarm and

ODU alarm are generated when ODU becomes faulty

RIM failure: PSU alarm with cable open/short alarm or modulator/demodulator alarms are active

Warning: modulator/demodulator circuitry is spread into LIM and RIM modules.


Branch-1 Power SupplyThis alarm is active when the PSU (Power Supply Unit) of one

RIM is switched off or is in failure condition

If the PSU is off, all the alarms of that RIM are activated:this alarm causes allRx Branch-1 alarms except those relevantRadio1 (is OFF)

Analysis order is:

PSUAll alarmedfrom now on

RT

IDU


Branch-1 Cable open/shortThis alarm is active when the following situations occur:- Cable open alarm no current through cable interface: ODU is not supplied… so situation looks like PSU alarm (Rx alarms) with cable alarm instead PSU alarm- Cable short alarm overcurrent/low voltage through cable interface

Caused by high VSWRvalue of damaged cable

Cable opensituation

If both alarms are active, 48 V source has no enough current


Alarms grouping : RT

These alarms come fromExternal fault: Rx power low alarm is

generated because of bad propagation or by remote terminal faulty

ODU failure: PSU fail alarm or RF VCO alarm or RF IF alarm is activated


Branch-x IDU-ODU Communication fail

This alarm occurs in ODU when on carrier used to receive command from IDU, are detected:

CRC errors

Loss of frame

This carrier is separated from carrier used for opposite direction (ODUIDU) and from TX or RX carriers


Branch-1 RT Radio Power Supply

This alarm is active when the Power Supply section of the radio doesn’t work properly or is in failure condition (voltage in input out of range).

Depending voltage value, radio can work.

When the under/over voltage is too high, radio is off and other alarms (cable open) cover this.


Branch 1 RT VCO fail

This alarm occurs when VCO in RF unit is not able to lock any frequencies.

Every problem in VCO causes alarms in both directions: RF unit is not able to convert IF Tx in RF Tx (Tx Power Low alarm) and RF Rx in IF Rx .

In this situation the alarm is active together with Tx Power Low and all Rx alarms because RF channel is not locked.

Tx & Rx


Branch 1 RT If fail

This alarm occurs when is not present IF signal inside ODU. There are two different IF signals but one alarm only.

IF Tx: the alarm is on with Tx Power Low

IF Rx: the alarm is on with all Rx alarms

When VCO is faulty, RF unit gives a IFRX signal made up of noise: this is enough to mantain IF fail alarm off.


Branch 1 RT Tx Power Low

This alarm occurs when Tx power is 3 dB under standard output of ODU-RF unit.

ATPC or manual attenuation do not affect this alarm that is given by internal failure of the radio.

This alarm can be activated by a manual operation also: Tx Transmitter off in Radio Branch - Settings

If both Rx Power Low and Tx Power Low are active, RF unit inside ODU is faulty

Tx


Branch 1 RT Rx Power LowThis alarm occurs when Rx power is under a defined threshold

Threshold value can be set for both branches in range - 40 dBm- 99 dBm in LCT - General preset

The alarm Rx Power Low is a branch alarm and it is used to drive Rx switch

Rx


Alarms grouping : UNIT

This group generates alarms when one of the units, the equipment consists of, is faulty or does not respond to controller polling:

Unit failUnit is not respondingUnit is missingUnit hardware mismatchUnit software mismatch


OTHERALARMS


Performance alarmsEvery performance measure can drive the relevant alarm if threshold is exceeded.

Threshold in sec. relevant 15 minutes alarm

Threshold in sec. relevant 24 hours alarm

Threshold in dB of Rx alarm

alarm counter reset

15 minutes alarms severity

If 0, alarm is disabled


Performance monitoring

15 min.

alarms

24 hours

alarms

P RX > -5

5 dBmPRX < -70 dBm

R = 15 minutes


Performance monitoring

15 min.

alarms

24 hours

alarms

Unavailable seconds for 16QAM

Practically seconds at 4QAM

R = 15 minutes


Recorder : Prx

date time dBm

LCT


Measures “ Performances ” is a group of measures, 15 minutes by 15 minutes, day by day, recorded by the equipment itself and downloaded on the PC.

These measures remain active also with SCT (and PC) disconnected.

“ Recorder Prx “ is the recording of Rx power on a log file inside the PC: every time a new value is measured a new “record” is written inside the log file with info of when (day, hour, minutes and seconds) and how much (dBm measured).

This recording remains active until SCT is connected to the equipment.


MU

X-D

EM

UX

RF

E1 LOOP

BASEBAND LOOP

IDU LOOP

RF LOOP

LIM

RIM 1 ODU 1

AL : available loops data direction: - towards the equipment that has enabled the loop (baseband, IDU, RF) - selectable for E1 loop - only local loops

MOD- DEMOD

LOOPSLOOPS

MUX-DEMUX

RF

E1 LOOP

BASEBAND LOOP

IDU LOOP RF LOOP

LIM

RIM 1 ODU 1

AL : available loops data direction: - towards the equipment that has enabled the loop (baseband, IDU, RF) - selectable for E1 loop - only local loops

MOD- DEMOD

Line side

Radio side

Branch 1

BASEBAND LOOP


loop:loop:external PRBSexternal PRBS

E1 loop line side : loop works with line enabled or not

E1 loop radio side : loop works with line enabled on local side and on remote side

Base Band, IDU, RF loop : loop works if line used is enabled local side and on remote side

Line side Radio side


loop:loop:internal PRBSinternal PRBS

E1 loop line side : …is before PRBS checking pointE1 loop radio side :loop works with line enabled on

remote side, indifferent* on local side.Base Band, IDU, RF loop : loop works any status of

local* and remote line__________________________ * PRBS enables automatically the local side of used line

Alarm OFF: signal is back!


Loop timeoutLoop timeout

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