1、QUESTION ITU-R 279/4*Satellite broadcasting of high-definition television(2009)The ITU Radiocommunication Assembly,consideringa) that a high-definition television (HDTV) service for direct satellite broadcasting is beingimplemented by some administrations;b) that a BSS plan needs to take into accoun
2、t the probable simultaneous presence ofstandard-definition television (SDTV) signals and HDTV signals;c) that considerable technical progress in space station technology, receiving equipmentperformance and in transmission methods has been made, and that this may improve the efficiencyof orbit and sp
3、ectrum use;d) that considerable technical progress in digital compression algorithms has been made,allowing broadcasting of multiple conventional TV programmes, and possibly more thanone HDTV programme in a single transponder,decides that the following Questions should be studied1 What are the optim
4、um HDTV system parameters and satellite channel configurationfor satellite transmission?2 What are the advantages and disadvantages of different digital coding and modulationschemes for HDTV satellite broadcasting in terms of spectrum efficiency and interference factors(inter- and intra-service shar
5、ing)?3 What are the provisions to achieve compatibility between HDTV and SDTV whichare required in the design of the space and ground segments for direct satellite broadcasting,with particular consideration to avoid prejudicing the existing satellite broadcasting Plans withinthe 11.7-12.7 GHz band,
6、for example: configuration of travelling wave tube amplifier to accommodate HDTV channels; spacecraft transponder channelization; receive terminal design features for the reception of HDTV and SDTV signals?NOTE 1 See Recommendation ITU-R BO.786 and Reports ITU-R BO.1075 and ITU-R BO.2007,further decides1 that the results of the studies on this Question should be included in appropriate Reports and/orRecommendations;2 that the above studies should be completed by 2011.Category: S1_* Former Question ITU-R 76/6.
