report mobile trial 26jul06-25jan07 v3 · 2019-05-10 · television broadcasts limited...
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Television Broadcasts Limited
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Report of Mobile TV Technical Trial
DVB-H Standard
Test period
26th July 2006 to 25th January 2007
Prepared by:
Transmission Network
Transmission Department
Engineering Division
Television Broadcasts Limited
Version: 3
Issued: 8th October 2007
Ref.: MobileTVTrial_01_2606-2501
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Introduction
TVB conducts Mobile TV technical trial as part of the DTT trial permit applied from OFTA in the
period from 9th July 2006 to 25th January 2007. This Report firstly presents the DVB-H test platform
setup, secondly provides field strength measurement in the studied coverage area and finally finding of
trial and follow up work are given.
Objective of Mobile TV field trial in first stage
In the preliminary test system setup, single DVB-H transmission test gear was installed at Temple Hill
station providing DVB-H signal source from hilltop site for signal strength measurement in the urban
area. The result of field strength measurement will provide useful data and test environment for enable
the study of radio propagation and penetration loss in different category of materials under DVB-H
signal operating in UHF frequency band.
Apparatus for DVB-H test transmission
The measurement include 4 classes of receiving conditions referring to ETSI TR 101 190 v1.2.1. The
target test area includes high density urban areas in Kowloon and Hong Kong north. The setup and trial
test in phase one include single station at Temple Hill. The second phase will extend DVB-H stations
include Golden Hill, Kowloon Peak and Mt. Nicholson to form a SFN system for DVB-H trial test.
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Figure 1: Single Temple Hill DVB-H transmitter station
The conceptual combined coverage area of DVB-H formed by 4 SFN stations is illustrated in following
Figure 2.
Figure 2: Proposed SFN overlapping areas formed by 4 DVB-H transmitter stations. Detail overlapping
coverage is subject to detailed design.
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System Overview
Based on Native DVB-H in non-hierarchical transmission setup, the system is designed to provide a
DVB-H stream to the Thomson Thales transmitter referring to diagram in Figure 3 below.
Figure 3: Diagram of DVB-H Transmitter and head-end equipment setup at Temple Hill station
Methodology
Field strength level, position data and demodulator status are recorded by Z-technology DSS-5600T
DVB-T Measurement/Mapping System, which is connected to a calibrated dipole antenna (length was
tuned to UHF channel 47) and is installed vertically on the roof of 24-seat lightweight bus at around 3
meter above ground level.
Assumption
1. Transmitting parameters of DVB-H signal
a. Modulation: QPSK CR:1/2, MPE FEC: 3/4
b. ERP: 1000W, single transmitting panel in vertical polarization
c. Transmitting from Temple Hill Station only
2. Minimum required C/N for demodulating DVB-H QPSK CR:1/2, MPE FEC: 3/4
a. 6.9dB1 for Portable Reception (neglects Doppler Effect)
b. 12.5dB2 for Mobile Reception (Doppler Effect is taken into account)
1 TR 102 377 V1.2.1 DVB-H Implementation Guidelines, page 77 & adds 3dB for
implementation headroom
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3. Receiver Noise Figure
a. 6dB3 for handheld device (5dB for receiver + 1dB for filter)
4. Antenna Gain
a. -7dBi4 for handheld antenna at 698MHz
b. -1dBd5 for vehicle mobile antenna in Band V
5. Location and Coverage Correction Factor (macro-scale)
a. 9dB6 for outdoor reception, good reception (coverage target >95%)
b. 14dB7 for indoor reception, good reception (coverage target >95%)
c. 13dB8 for mobile reception, good reception (coverage target >99%)
Hence, we have
2 TR 102 377 V1.2.1 DVB-H Implementation Guidelines, page 78 & 80, ‘Typical’ reference
receiver 3 TR 102 377 V1.2.1 DVB-H Implementation Guidelines, page 81 & 75 4 TR 102 377 V1.2.1 DVB-H Implementation Guidelines, page 79 5 TR 102 377 V1.2.1 DVB-H Implementation Guidelines, page 87 6 TR 102 377 V1.2.1 DVB-H Implementation Guidelines, page 84 7 TR 102 377 V1.2.1 DVB-H Implementation Guidelines, page 86 8 TR 102 377 V1.2.1 DVB-H Implementation Guidelines, page 87
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DVB-H Class APortableOutdoorQPSK, CR: 1/2,MPE FEC 3/4
DVB-H Class BPortable IndoorQPSK, CR: 1/2,MPE FEC 3/4
DVB-H Class CMobile OutdoorQPSK, CR: 1/2,MPE FEC 3/4
DVB-H Class DMobile IndoorQPSK, CR: 1/2,MPE FEC 3/4
Frequency MHz 682 682 682 682Bandwidth MHz 7.61 7.61 7.61 7.61Noise Power at receiver input (kTB) dBm -105.2 -105.2 -105.2 -105.2
Receiver Noise Figure dB 6 6 6 6
Required C/N dB 6.9 6.9 12.5 12.5
dBm -92.3 -92.3 -86.7 -86.7dBµV 16.5 16.5 22.1 22.1
Feeder Loss dB 0 0 0 0dBd -9.2 -9.2 -1.0 -9.2dBi -7.0 -7.0 1.2 -7.0
Minimum Required Field Strength atReceiving Antenna
dBµV/m 48.6 48.6 46.1 54.2
Building Penetration Loss dB - 11 - -Vehicle Entry Loss dB - - - 7Minimum Required Field Strength usedin FS Prediction at Open Area
dBµV/m 48.6 59.6 46.1 61.2
Location Correction Factor dB 9 14 13 13
Required Minimum Median FieldStrength (The target level for achiving theconfidence of 95/99% coverage area has theabove min. req, field strength)
dBµV/m 57.6 73.6 59.1 74.2
Min. Required Input Power at ReceiverInput
Antenna Gain
Table 1: Calculation of required minimum median field strength for Class A, B, C & D Mobile TV
reception under DVB-H
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Therefore, the required minimum Median Field Strength for DVB-H (QPSK 1/2, MPE FEC 3/4) is:
Class A & C: 58 dBµV/m
Class B & D: 74 dBµV/m
Remark:-
1. Since Field Strength were measured at the roof of moving vehicle, the expected FS at pedestrian
walkway should be lower due to complex circumstance in Hong Kong, some additional correct
factor may need taking into account in Class A reception;
2. Location and coverage correction factor is quoted from ETSI documentation which is a statistical
correction factor for predication in foreign country; it may need higher value of location and
coverage correction factor (macro-scale) due to special complexity in Hong Kong circumstance.
3. The required C/N ratio for DVB-H demodulation is needed to verify, and it may not be consistent
with Thales EyePhone.
Measurement Data
Field strength measurement along the test routes was carried out based on the transmission parameter
setup described in the above; the data was collected for analysis. The measurement data is summarized
below:
Number of count are selected from the collected field strength equal and larger than 58 dBµV/m in the
test route: 7955
Maximum field strength: 90.4 dBµV/m
Mean field strength: 69.8 dBµV/m
Standard Deviation: 7.34 dB
A. Test routes of DTT survey mobile with field strength collected in range from 58 dBµV/m to 90
dBµV/m include:
1. Kwun Tong bypass highway, Kowloon Bay, Kowloon City and Kowloon East;
2. West Kowloon expressway, Nathan Road and Cheung Sha Wan Road, and
3. Traffic road facing to Victoria harbour in North Hong Kong Island between Shau Kei Wan and
Sai Wan.
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B. Test routes of DTT survey mobile with field strength collected in range from 74 dBµV/m to 90
dBµV/m continuously include:
1. Part of Kwun Tong Bypass, Kowloon Bay, Kowloon City, and
2. Hong Kong Island North in section from Shau Kei Wan to Causeway Bay along the Island
Eastern Corridor
For Class A & C (Portable Outdoor and Mobile Outdoor) the required minimum median field strength
for DVB-H (QPSK 1/2, MPE FEC 3/4) distributes in the whole test route. On the other hand, the
required minimum median field strength for Class B & D (Portable indoor and Mobile indoor)
distribute in limited area along the test route because of building shadow causing minimum median
field strength can not be reached.
Conclusion
Single DVB-H transmitter station at Temple Hill with 1kW E.R.P. can provide attractive field strength
along the test routes for Class A & C services (Portable Outdoor and Mobile Outdoor) in dense urban
area based on minimum median field strength requirement. Because of building shadow and extra 16
dB to be required for Class B & D services (Portable indoor and Mobile indoor), the coverage area is
needed to be improved by means of more hill-top DVB-H stations and even more roof-top gap-filler
stations in order to provides useful coverage areas in environment of Hong Kong.
Follow up work
In order to collect useful measurement data and radio propagation characteristic to enable Mobile TV
network planning, it is required to conduct further trial test by means of increasing number of DVB-H
stations including hill-top and roof-top under SFN configuration.
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FIGURES
Figure 1: Single Temple Hill DVB-H transmitter station ......................................................................... 3
Figure 2: Proposed SFN overlapping areas formed by 4 DVB-H transmitter stations. Detail
overlapping coverage is subject to detailed design. .................................................................................3
Figure 3: Diagram of DVB-H Transmitter and head-end equipment setup at Temple Hill station ..........4
TABLE
Table 1: Calculation of required minimum median field strength for Class A, B, C & D Mobile TV
reception under DVB-H............................................................................................................................6
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