1、 Recommendation ITU-R BS.1660-7 (10/2015) Technical basis for planning of terrestrial digital sound broadcasting in the VHF band BS Series Broadcasting service (sound) ii Rec. ITU-R BS.1660-7 Foreword The role of the Radiocommunication Sector is to ensure the rational, equitable, efficient and econo
2、mical 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
3、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 Resolution ITU-R 1. Forms to be use
4、d 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 information database can also be found. Ser
5、ies 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 Fixed service M Mobile, radiodeter
6、mination, 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 systems SM Spectrum management SNG Sat
7、ellite 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 rights reserved. No part of this publ
8、ication may be reproduced, by any means whatsoever, without written permission of ITU. Rec. ITU-R BS.1660-7 1 RECOMMENDATION ITU-R BS.1660-7* Technical basis for planning of terrestrial digital sound broadcasting in the VHF band (Question ITU-R 56/6) (2003-2005-2005-2006-2011-2012-2015) Scope This R
9、ecommendation describes the planning criteria, which could be used for planning of terrestrial digital sound broadcasting in the VHF band, for Digital Systems A, F and G of Recommendation ITU-R BS.1114. The ITU Radiocommunication Assembly, considering a) Recommendations ITU-R BS.774 and ITU-R BS.111
10、4; b) ITU-R Digital Sound Broadcasting Handbook Terrestrial and satellite digital sound broadcasting to vehicular, portable and fixed receivers in the VHF/UHF bands, recommends 1 that the planning criteria as described in Annex 1 for Digital System A and Annex 2 for Digital System F and Annex 3 for
11、Digital System G could be used for planning of terrestrial digital sound broadcasting in the VHF band. Annex 1 Technical basis for planning of terrestrial digital sound broadcasting System A (T-DAB) in the VHF band 1 General This Recommendation contains relevant T-DAB system parameters and network c
12、oncepts, including a description of single frequency networks (SFNs). The receiving antenna, which is assumed to be representative for mobile and portable reception, has a height of 1.5 m above ground level, omnidirectional with a gain slightly lower than a dipole. The field strength prediction meth
13、od relies on curves for 50% locations, 50% time for the wanted signal and 50% locations, 1% time for the unwanted signal. For the calculation of tropospheric (1% time) and continuous (50% time) interference, see Recommendation ITU-R BT.655. * The Administration of the Syrian Arab Republic is not in
14、a position to accept the content of this Recommendation, nor for it to be used as a technical basis for the planning of sound broadcasting in the VHF band, at the forthcoming Regional Radiocommunication Conferences planning of the digital terrestrial broadcasting service in parts of Regions 1 and 3.
15、 2 Rec. ITU-R BS.1660-7 The required location percentage for T-DAB services is 99%. Therefore, taking a standard deviation of 5.5 dB, an increase of 13 dB (2.33 5.5 dB) shall be applied to the field strength values (50% locations) in order to obtain the 99% location values required for planning a T-
16、DAB service. The propagation curves used for planning relate to a receiving antenna height of 10 m above ground, whereas a T-DAB service will be planned primarily for mobile reception, i.e., with an effective receiving antenna height of about 1.5 m. An allowance of 10 dB is necessary to convert the
17、minimum required T-DAB field strength at a vehicle antenna height of 1.5 m to the equivalent value at 10 m. 2 Minimum wanted field strength used for planning Table 1 contains values for VHF Band III with the inclusion of a correction of 13 dB for location percentage and of 10 dB for height gain. The
18、 below given minimum median equivalent field strength represents the minimum wanted field strength used for planning. The values shown in Table 1 are applied to mobile reception. TABLE 1 Minimum median equivalent field strength (dB(V/m) at an antenna height of 10 m Frequency band Band III Minimum eq
19、uivalent field strength (dB(V/m) 35 Location percentage correction factor (50% to 99%) (dB) +13 Antenna height gain correction (dB) +10 Minimum median equivalent field strength for planning (dB(V/m) 58 3 Unwanted emissions 3.1 Spectrum masks for T-DAB out-of-band emissions The out-of-band radiated s
20、ignal in any 4 kHz band should be constrained by one of the masks defined in Fig. 1. The solid line mask should apply to VHF transmitters operating in critical cases. The dashed line mask should apply to VHF transmitters operating in uncritical cases or in the 1.5 GHz band and the dotted line mask s
21、hould apply to VHF transmitters operating in certain areas where frequency block 12D is used. The level of the signal at frequencies outside the normal 1.536 MHz bandwidth can be reduced by applying an appropriate filtering. Rec. ITU-R BS.1660-7 3 FIGURE 1 Out-of-band spectrum masks for a transmissi
22、on signal of System A BS .1660-01100908070605052454030201001009050784030201002656607071801061 101201261303 2 1 1 2 3f00.772.5 1.5 0.5 0.5 1.5 2.52.21.750.970.770.971.752.2Ratioofout-of-bandpowermeasuredin4kHzbandwidthtoin-bandpowermeasuredin4kHzbandwidth(dB)Ratioofout-of-bandpowermeasuredin4kHzbandw
23、idthtototalpowerin1.5MHzofaSystemAblock(dB)F r e que nc y di f f e r e nc e f r om c e nt r e f r e que nc y ( M H z )S pe c t r um m a s k f or V H F S ys t e m A t r a ns m i t t e r s ope r a t i ng i n unc r i t i c a l c a s e sor i n t he 1.5 G H z ba ndS pe c t r um m a s k f or V H F S ys t
24、e m A t r a ns m i t t e r s ope r a t i ng i n c r i t i c a l c a s e sS pe c t r um m a s k f or V H F S ys t e m A t r a ns m i t t e r s ope r a t i ng i n c e r t a i n a r e a s w he r ef r e que nc y bl oc k 12D i s us e d4 Rec. ITU-R BS.1660-7 Out-of-band spectrum table for a transmission s
25、ignal of System A Frequency relative to the centre of the 1.54 MHz channel (MHz) Relative level (dB) Spectrum mask for VHF System A transmitters operating in uncritical cases or in the 1.5 GHz band 0.97 26 0.97 56 3.0 106 Spectrum mask for VHF System A transmitters operating in critical cases 0.77 2
26、6 0.97 71 1.75 106 3.0 106 Spectrum mask for VHF System A transmitters operating in certain areas where frequency block 12D is used 0.77 26 0.97 78 2.2 126 3.0 126 Appendix 1 to Annex 1 Planning criteria as used by a group of countries in the Wiesbaden 1995 Special Arrangement 1 Position of frequenc
27、y blocks in Band III Table 2 shows a harmonized channelling plan. This is based on tuning increments of 16 kHz and guardbands of 176 kHz between adjacent T-DAB frequency blocks. Within each 7 MHz television channel, four T-DAB frequency blocks are accommodated. In order to enhance compatibility with
28、 the sound carrier(s) in 7 MHz TV systems, the guardbands for T-DAB frequency blocks A in Channel N and D in Channel N-1 are 320 kHz or 336 kHz. The position of T-DAB frequency blocks within Channel 12 is shown as an example in Fig. 2. Rec. ITU-R BS.1660-7 5 TABLE 2 T-DAB frequency blocks T-DAB bloc
29、k number Centre frequency (MHz) Frequency range (MHz) Lower guardband(1) (kHz) Upper guardband(1) (kHz) 5A 174.928 174.160-175.696 176 5B 176.640 175.872-177.408 176 176 5C 178.352 177.584-179.120 176 176 5D 180.064 179.296-180.832 176 336 6A 181.936 181.168-182.704 336 176 6B 183.648 182.880-184.41
30、6 176 176 6C 185.360 184.592-186.128 176 176 6D 187.072 186.304-187.840 176 320 7A 188.928 188.160-189.696 320 176 7B 190.640 189.872-191.408 176 176 7C 192.352 191.584-193.120 176 176 7D 194.064 193.296-194.832 176 336 8A 195.936 195.168-196.704 336 176 8B 197.648 196.880-198.416 176 176 8C 199.360
31、 198.592-200.128 176 176 8D 201.072 200.304-201.840 176 320 9A 202.928 202.160-203.696 320 176 9B 204.640 203.872-205.408 176 176 9C 206.352 205.584-207.120 176 176 9D 208.064 207.296-208.832 176 336 10A 209.936 209.168-210.704 336 176 10B 211.648 210.880-212.416 176 176 10C 213.360 212.592-214.128
32、176 176 10D 215.072 214.304-215.840 176 320 11A 216.928 216.160-217.696 320 176 11B 218.640 217.872-219.408 176 176 11C 220.352 219.584-221.120 176 176 11D 222.064 221.296-222.832 176 336 12A 223.936 223.168-224.704 336 176 12B 225.648 224.880-226.416 176 176 12C 227.360 226.592-228.128 176 176 12D
33、229.072 228.304-229.840 176 (1) In arriving at these values, it has been assumed that the T-DAB transmitting and receiving equipment must allow for the use of adjacent T-DAB frequency blocks in adjacent areas, i.e., using a 176 kHz guardband. 6 Rec. ITU-R BS.1660-7 FIGURE 2 Position of T-DAB blocks
34、in channel 12 BS .16 60 -02 2 T-DAB reference network Reference networks are used for the planning of allotments. The characteristics of the reference networks represent a reasonable compromise between the density of the transmitters required to support the desired coverage and the potential to reus
35、e the same frequency block with other programme content in other areas. A reference network is a tool for developing appropriate values for separation distances and for estimating how much interference a typical SFN might produce at a given distance. 2.1 T-DAB transmitter network structures T-DAB st
36、ations or networks consist of one of three basic models or combinations thereof: a single transmitter; an SFN using non-directional transmitting antennas, also referred to as an “open network”; an SFN using directional transmitting antennas along the periphery of the coverage area, also referred to
37、as a “closed network”. 2.2 Definitions The reference point is the point on the boundary of a reference network from which outgoing interference is calculated, see also Fig. 4. Incoming interference is calculated at the same point. In the following text, two distances are defined; see also Fig. 3. Th
38、e separation distance is the distance required between the borders (or peripheries) of two coverage areas served by either T-DAB services or by two different services. There will often be two separation distances, one for each service, because of different field strengths to be protected or because
39、of different protection ratios for the two services. In such cases the longer of these two distances shall be used. The transmitter distance is the distance between adjacent transmitter sites in an SFN. Rec. ITU-R BS.1660-7 7 FIGURE 3 Definition of distances for different network structures (SFN, si
40、ngle transmitter) BS .1660-03T r a ns m i t t e r di s t a nc eS e pa r a t i on di s t a nc eT r a ns m i t t e rW i dt h of t he c ove r a ge a r e aA r e a t o bec ove r e dT r a ns m i t t e rS e pa r a t i on di s t a nc eT r a ns m i t t e rA r e a t o be c ove r e dW i dt h of t he c ove r a
41、ge a r e aW a nt e d S F N( 7 t r a ns m i t t e r s )U nw a nt e d S F N( 7 t r a ns m i t t e r s )W a nt e d t r a ns m i t t e r U nw a nt e d t r a ns m i t t e r8 Rec. ITU-R BS.1660-7 FIGURE 4 Information related to the interfering field strength calculation for the reference network BS .1660-
42、04R e f e r e nc e po i ntI nt e r f e r i ng f i e l d s t r e ngt h i sc a l c ul a t e d a l ong t hi s l i neD i s t a nc e f r om t hebor de r of t he S F NL a nd L a nd or s e a6 0km2.3 T-DAB reference SFN In interfering field strength calculations the contributions from all transmitters of th
43、e reference network are added using the power sum method. In the case of mixed land-sea paths, field strengths are first calculated individually for an all-land path and an all-sea path, each of the same distance as the mixed path concerned. A linear interpolation is then performed between the field
44、 strengths for all-land and all-sea paths at the required distance from the border of the SFN according to the following formula: )(LSTSLM EEddEE where: EM : field strength for a mixed land-sea path EL : field strength for an all-land path ES : field strength for an all-sea path dS : length of the s
45、ea path dT : length of the total path. All field strengths are in dB(V/m). In all-sea path calculations it is assumed that the reference network and its coverage area are on land and that the sea starts from the edge of the coverage area. For land paths a terrain roughness of 50 m is assumed. 2.3.1
46、Reference network structure The reference network suitable for the frequency allotment process is defined as follows (see also Fig. 4): Hexagonal structure: closed Transmitter distance: 60 km Transmitting antenna height: 150 m Rec. ITU-R BS.1660-7 9 Central transmitter effective radiated power (e.r.
47、p.): 100 W Radiation pattern of the central transmitter: omnidirectional Peripheral transmitter e.r.p.: 1 kW Radiation pattern of peripheral transmitters: see Fig. 5 Main lobe of directional antennas: in the direction of the central transmitter. FIGURE 5 Radiation pattern of the peripheral transmitt
48、ers BS .16 60 -05A ngl e ( de gr e e s )e.r.p. comparedwiththemaximume.r.p.(dB)100 0 2080 60 40 20 40 60 80 100024681012When using the field strength prediction method described in this Appendix, the reference network produces the required coverage inside the network. The effective wanted field stre
49、ngth on the border of the reference network is about 3 dB higher than the minimum field strength for planning. This makes it possible to allow 3 dB more interference at the edge of the network. Thus the maximum interfering field strength from another co-channel T-DAB service on the border of the reference network is: 3 PCPREE M i nWM a xI where: MaxIE : maximum interfering field strength on the border of the reference network MinWE : minimum median wanted field st
