1、 Recommendation ITU-R BT.1368-12 (02/2015) Planning criteria, including protection ratios, for digital terrestrial television services in the VHF/UHF bands BT Series Broadcasting service (television) ii Rec. ITU-R BT.1368-12 Foreword The role of the Radiocommunication Sector is to ensure the rationa
2、l, 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 Radiocommu
3、nication Sector are performed by World and Regional Radiocommunication Conferences and Radiocommunication Assemblies supported by Study Groups. Policy on Intellectual Property Right (IPR) ITU-R policy on IPR is described in the Common Patent Policy for ITU-T/ITU-R/ISO/IEC referenced in Annex 1 of Re
4、solution ITU-R 1. Forms to be used for the submission of patent statements and licensing declarations by patent holders are available from http:/www.itu.int/ITU-R/go/patents/en where the Guidelines for Implementation of the Common Patent Policy for ITU-T/ITU-R/ISO/IEC and the ITU-R patent informatio
5、n database can also be found. Series of ITU-R Recommendations (Also available online at http:/www.itu.int/publ/R-REC/en) Series Title BO Satellite delivery BR Recording for production, archival and play-out; film for television BS Broadcasting service (sound) BT Broadcasting service (television) F F
6、ixed service M Mobile, radiodetermination, amateur and related satellite services P Radiowave propagation RA Radio astronomy RS Remote sensing systems S Fixed-satellite service SA Space applications and meteorology SF Frequency sharing and coordination between fixed-satellite and fixed service syste
7、ms SM Spectrum management SNG Satellite news gathering TF Time signals and frequency standards emissions V Vocabulary and related subjects Note: This ITU-R Recommendation was approved in English under the procedure detailed in Resolution ITU-R 1. Electronic Publication Geneva, 2015 ITU 2015 All righ
8、ts reserved. No part of this publication may be reproduced, by any means whatsoever, without written permission of ITU. Rec. ITU-R BT.1368-12 1 RECOMMENDATION ITU-R BT.1368-12 Planning criteria, including protection ratios, for digital terrestrial television services in the VHF/UHF bands (1998-1998-
9、2000-2002-2004-2005-2006-2007-2009-2011-2013-2014-2015) Scope This Recommendation defines planning criteria for various methods of providing digital terrestrial television services in the VHF/UHF bands. Keywords DTTB, ATSC, DVB-T, ISDB-T, DTMB, planning criteria, protection ratio, overload threshold
10、 The ITU Radiocommunication Assembly, considering a) that systems have been developed for the transmission of digital terrestrial television services (DTTS) in the VHF/UHF bands; b) that the VHF/UHF television bands are still occupied by analogue television services; c) that the analogue television
11、services will remain in use in some administrations for a considerable period of time; d) that the availability of consistent sets of planning criteria agreed by administrations will facilitate the planning of digital terrestrial television services; e) that parts of the VHF/UHF television bands are
12、 shared with other primary services; f) that sharing between digital terrestrial television broadcasting (DTTB) and some other primary services is an evolving situation; g) that the protection ratios established for the protection of digital terrestrial television need to be at the threshold of sign
13、al failure, recommends 1 that the relevant protection ratios (PRs) and the relevant minimum field strength values given in Annexes 1, 2, 3 and 4 and the additional information given in Annexes 5, 6, 7 and 8 should be used as the basis for frequency planning for digital terrestrial television service
14、s. Introduction This Recommendation contains the following Annexes: Annex 1 Planning criteria for ATSC digital terrestrial television systems in the VHF/UHF bands Annex 2 Planning criteria for DVB-T digital terrestrial television systems in the VHF/UHF bands Annex 3 Planning criteria for ISDB-T digi
15、tal terrestrial television systems in the VHF/UHF bands Annex 4 Planning criteria for DTMB digital terrestrial television systems in the VHF/UHF bands Annex 5 Other planning factors 2 Rec. ITU-R BT.1368-12 Annex 6 Subjective comparison method (SCM) with a reference interferer for assessment protecti
16、on ratios for analogue television systems Annex 7 Failure point assessment methods Annex 8 Tropospheric and continuous interference General The RF protection ratio is the minimum value of wanted-to-unwanted signal ratio, usually expressed in decibels at the receiver input. The reference level of the
17、 digital signal is defined as the r.m.s. value of the emitted signal power within the channel bandwidth. It should preferably be measured with a thermal power meter. Historically, protection ratio values for wanted digital signals were measured with a 60 dBm receiver input power. Where possible, pro
18、tection ratios for digital TV systems are derived from measurements using a range of signal levels. The reference level of the analogue vision-modulated signal is defined as the r.m.s. value of the vision carrier at peaks of the modulation envelope. All protection ratio values for wanted analogue si
19、gnals are measured with a receiver input power of 39 dBm (70 dB(V) at 75 ). 1 Wanted digital terrestrial television systems The protection ratios for digital terrestrial television systems apply to both continuous and tropospheric interference. The protection ratios refer to the centre frequency of
20、the wanted digital terrestrial television system. Because a digital television receiver needs to operate successfully in the presence of high level analogue signals on nearby channels, a high degree of receiver front-end linearity is required. The protection ratios for digital terrestrial television
21、 systems as the interfering system are those for the case where the wanted and unwanted signals are not synchronized and/or do not have a common programme source. Results relevant to single frequency networks (SFN) are yet to be developed and simple aggregate power sum calculations taking into accou
22、nt transmitter sites and propagation for each transmitter in the network may be used as an initial guide. For the digital terrestrial television system, ATSC, the protection ratios are measured for a BER = 3 106 at the input of the MPEG-2 demultiplexer. For the digital terrestrial television systems
23、 (digital video broadcasting-terrestrial (DVB-T) and integrated service digital broadcasting-terrestrial (ISDB-T) the protection ratios are measured between the inner and outer codes, before Reed-Solomon decoding, for a BER = 2 104; this corresponds to a BER 1 1011 at the input of the MPEG-2 demulti
24、plexer. For domestic receivers it may not be possible to measure the BER before Reed-Solomon decoding. The BER for such cases is under study. For digital television terrestrial multimedia broadcasting (DTMB), the protection ratios are measured at the output of BCH, BER = 3 106 at the input of demult
25、iplexer. To reduce the number of measurements and tables, it is proposed that protection ratio measurements for DVB-T systems should preferably be made with the following three modes shown in Table 1. Protection ratio values for the different required operational modes for fixed, portable or mobile
26、reception can be calculated from the given measured values. The tabulated scaling values for varying reception channel qualities from Gaussian, through Ricean, to Rayleigh are provided in Table 50 4 of Annex 2. Rec. ITU-R BT.1368-12 3 TABLE 1 Proposed preferable DVB-T mode types for measurements on
27、protection ratios Modulation Code rate C/N(1) (dB) Bit rate(2) (Mbit/s) QPSK 2/3 6.9 7 16-QAM 2/3 13.1 13 64-QAM 2/3 18.7 20 (1) The figures are given for a Gaussian channel (including a typical implementation margin) for a BER 1 1011. (2) For a guard interval of 1/4. To reduce the number of measure
28、ments and tables, it is proposed that protection ratio measurements for DTMB systems should preferably be made with the following 11 modes shown in Table 2. TABLE 2 Proposed preferable DTMB mode types for measurements on protection ratios Modulation Code rate C/N(1) (dB) Bit rate(2) (Mbit/s) 4-QAM 0
29、.4 2.5 5.414 16-QAM 0.4 8.0 10.829 64-QAM 0.4 14.0 16.243 4-QAM 0.6 4.5 8.122 16-QAM 0.6 11.0 16.243 64-QAM 0.6 17.0 24.365 4-QAM-NR 0.8 2.5 5.414 4-QAM 0.8 7.0 10.829 16-QAM 0.8 14.0 21.658 32-QAM 0.8 16.0 27.072 64-QAM 0.8 22.0 32.486 (1) The figures are given for a Gaussian channel at BCH output
30、BER 3 106. (2) For a guard interval of 1/9 and RF bandwidth 8 MHz. 2 Wanted analogue terrestrial television systems Measurements of protection ratios for the vision signal of a wanted analogue terrestrial television system should preferably be made with the subjective comparison method with a sine-w
31、ave reference interferer described in Annex 6. 4 Rec. ITU-R BT.1368-12 The values of protection ratio quoted apply to interference produced by a single source. Except where otherwise stated, the ratios apply to tropospheric, T, interference and correspond closely to a slightly annoying impairment co
32、ndition. They are considered to be acceptable only if the interference occurs for a small percentage of the time, not precisely defined but generally considered to be between 1% and 10%. For substantially non-fading unwanted signals, it is necessary to provide a higher degree of protection and ratio
33、s appropriate to continuous, C, interference should be used (see Annex 8). When the wanted signal is an analogue television signal, two or more protection ratio values should be considered, one for the protection ratio of the vision signal and others for the protection ratios of sound signals. The m
34、ost stringent value should then be used. Significantly strong wanted input signals can require higher protection ratio values because of non-linear effects in the receiver. For 625-line systems, the reference impairment levels are those which correspond to co-channel protection ratios of 30 dB and 4
35、0 dB, when two-thirds line offset is used, see Recommendation ITU-R BT.655. These conditions approximate to impairment grades 3 (slightly annoying) and 4 (perceptible but not annoying) and apply to tropospheric, T, and continuous, C, interference, respectively. Rec. ITU-R BT.1368-12 5 Table of Conte
36、nts Page 1 Wanted digital terrestrial television systems 2 2 Wanted analogue terrestrial television systems 3 Annex 1 Planning criteria for ATSC digital television systems in the VHF/UHF bands . 17 1 Protection ratios for ATSC wanted digital terrestrial television signals 17 1.1 Protection of an ATS
37、C digital terrestrial television signal interfered with by an ATSC digital terrestrial television signal . 17 1.2 Protection of ATSC digital terrestrial television interfered with by analogue terrestrial television 18 2 Protection ratios for wanted analogue terrestrial television signals interfered
38、with by unwanted ATSC digital terrestrial television signals . 19 2.1 Protection ratios for 525-line television systems 19 2.2 Protection ratios for 625-line television systems 20 3 Protection ratios for sound signals of wanted analogue terrestrial television signals interfered with by unwanted ATSC
39、 digital terrestrial television signals 21 3.1 Protection for NTSC sound signals (BTSC MTS system and SAP) interfered with by an ATSC digital television signal (see Note 1) . 21 4 Minimum field strengths for ATSC terrestrial digital television . 22 Attachment 1 to Annex 1 Derivation by the figure of
40、 merit method 23 Annex 2 Planning criteria for DVB-T digital television systems in the VHF/UHF bands . 24 1 Protection ratios for DVB-T wanted digital terrestrial television signals 24 1.1 Protection of a DVB-T digital terrestrial television signal interfered with by a digital terrestrial television
41、 signal . 25 1.2 Protection of DVB-T digital terrestrial television interfered with by analogue terrestrial television 28 1.3 Protection of DVB-T digital terrestrial television signal from CW or FM signals . 31 1.4 Protection of DVB-T digital terrestrial television signals from T-DAB signals 32 1.5
42、Protection of DVB-T from wideband signals other than terrestrial broadcasting 33 2 Protection ratios for wanted analogue terrestrial television signals interfered with by unwanted DVB-T digital terrestrial television signals . 43 2.1 Protection ratios for 625-line television systems 44 6 Rec. ITU-R
43、BT.1368-12 Page 3 Protection ratios for sound signals of wanted analogue terrestrial television signals interfered with by unwanted DVB-T digital terrestrial television signals 47 3.1 Protection for FM, AM and NICAM sound signals of analogue television systems interfered with by DVB-T digital terres
44、trial television signals . 48 4 Correction factors for different wanted DVB-T system variants and different reception conditions 49 5 Protection ratios for a T-DAB signal interfered with by an unwanted digital terrestrial television signal 51 6 Minimum field strengths for DVB-T terrestrial digital t
45、elevision, fixed reception . 51 7 Minimum median field strength for mobile DVB-T reception 52 7.1 Required average C/N for mobile reception . 52 7.2 Receiver noise figure 54 8 Minimum median field strength for hand held pedestrian indoor, pedestrian outdoor and mobile DVB-H reception . 54 8.1 Channe
46、l models for hand held pedestrian indoor and outdoor reception . 54 8.2 Channel model for mobile reception 56 8.3 Required average C/N for hand held indoor and outdoor reception . 56 8.4 Required average C/N for hand held indoor and outdoor reception . 57 8.5 Receiver noise figure 58 Attachment 1 to
47、 Annex 2 Calculation of minimum field strength and minimum median equivalent field strength . 59 Attachment 2 to Annex 2 . 60 Attachment 3 to Annex 2 65 Annex 3 Planning criteria for ISDB-T digital television system in the VHF/UHF bands 65 1 Protection ratios for ISDB-T wanted digital terrestrial te
48、levision signals 65 1.1 Protection of an ISDB-T digital terrestrial television signal interfered with by digital television signals . 66 1.2 Protection of an ISDB-T digital terrestrial television signal interfered with by analogue terrestrial television signals . 68 2 Protection ratios for wanted an
49、alogue terrestrial television signals interfered with by unwanted ISDB-T digital terrestrial television signals. 71 2.1 Protection ratios for 525-line television systems 71 2.2 Protection ratios for 625-line television systems 72 Rec. ITU-R BT.1368-12 7 Page 3 Protection ratios for sound signals of wanted analogue terrestrial television systems interfered with by ISDB-T unwanted digital terrestrial television system . 72 3.1 Protection for NTSC sound signals interfered with by an ISDB-T digital television signal
