1、HTTP:/WWW.ITU.INT/DMS_PUB/ITU-R/OPB/QUE/R-QUE-SG06.9-2001-MSW-E.DOC 18.09.03 15.07.10Radiocommunication Study Group 6QUESTION ITU-R 9/6*Universal transmitters and retransmitters for both analogue anddigital terrestrial TV broadcasting(2001)The ITU Radiocommunication Assembly,consideringa) that intro
2、duction and implementation of digital terrestrial TV broadcasting should berealized taking account of existing terrestrial broadcasting;b) that digitalization of TV distributional network leads to a radical increase in the number ofprograms delivered by the network and thus to the need for additiona
3、l transmitters andretransmitters to be installed;c) that most of additional transmitters and retransmitters are currently being installed forexisting terrestrial broadcasting;d) that there are advantages in reuse of currently installed transmitters and retransmitters,i.e. their further use for digit
4、al terrestrial TV broadcasting;e) that such reuse is especially important when digital terrestrial TV broadcasting are beingimplemented not in addition to existing terrestrial TV broadcasting but as their replacement,because of the lack of frequencies;f) that the reuse of currently installed transmi
5、tters and retransmitters for digital terrestrial TVbroadcasting should be preferably realized with a minimum alteration or no alteration at all;g) that signal transfer into the broadcasting frequency band, amplification and transmission arecommon function for both analogue transmitters (with amplitu
6、de modulated PAL/NTSC/SECAMinput signal) and digital transmitters (with multiprogram digital TV signal modulated for digitalbroadcasting, or HDTV, as input signal);h) that part of the functions of present analogue transmitters and retransmitters i.e. amplitudemodulation of the TV signal and sideband
7、 filtering can be shifted to the digital decoders of the_* This Question should be brought to the attention of the International StandardizationOrganization/International Electrotechnical Commission (ISO/IEC).INTERNATIONAL TELECOMMUNICATION UNIONRADIOCOMMUNICATIONSTUDY GROUPSDocument 6/1-E8 June 200
8、3Original: English- 2 -6/1-EHTTP:/WWW.ITU.INT/DMS_PUB/ITU-R/OPB/QUE/R-QUE-SG06.9-2001-MSW-E.DOC 18.09.03 15.07.10distributional network, which will implement these procedures digitally and with a higher quality byproducing amplitude modulated PAL/NTSC/SECAM signals with a partly suppressed sideband
9、andalso frequency modulated audio;j) that in case if newly installed transmitters and retransmitters will only have to transfer theamplitude modulated PAL/NTSC/SECAM signals (produced by above mentioned digital decoders)into the broadcasting frequency band, to amplify and to transmit them, they also
10、 would be able torealize this task with a multiprogram digital TV signal modulated for digital broadcasting (orHDTV signal);k) that such simplified universal transmitters and retransmitters must transfer, amplify andtransmit a multiprogram digital TV signal, modulated for digital broadcasting, such
11、a way that itwill not interfere with the adjacent frequency channels;l) that such universal transmitters and retransmitters for both analogue and digital terrestrialbroadcasting and also digital decoders (producing amplitude modulated PAL/NTSC/SECAMsignals with a partly suppressed sideband and frequ
12、ency modulated audio), should meet specialrequirements,decides that the following Question should be studied1 What are the special requirements for amplitude modulated PAL/NTSC/SECAM signalwith a partly suppressed sideband, produced by digital decoder of the distributional network forfurther transfe
13、r, amplification and transmission by universal transmitter and retransmitter used forexisting terrestrial broadcasting?2 What are the special requirements for frequency modulated audio signal, produced bydigital decoder of the distributional network for further transfer, amplification and transmissi
14、on byuniversal transmitter and retransmitter used for existing terrestrial broadcasting?3 What are the special requirements for a universal transmitter used for digital terrestrial TVbroadcasting to provide its non interference with existing terrestrial broadcasting?4 What kind of additional pre-cor
15、rection and filtering is necessary, in case when a universaltransmitter is used for digital terrestrial TV broadcasting, to provide its complete non interferencewith existing terrestrial broadcasting?5 What are the requirements for TV studio equipment to make it compatible with universaltransmitter
16、in case when such transmitter is being feeded directly by TV studio output signal?6 For what range of output RF broadcasting power the use of transmitters and retransmittersis possible without alteration of feeder and antenna systems?further decides1 that the results of the above studies should be included in (a) Recommendation(s);2 that the above studies should be completed by 2005._
