1、C:DOCUMENTS AND SETTINGSQGV33745MY DOCUMENTSDOWNLOADSR-QUE-SG06.53-1993-MSW-E.DOC 22.10.03 15.07.10 QUESTION ITU-R 53/6 Standards for the transmission of several sound signals in one television channel in terrestrial or satellite broadcasting including high-definition and enhanced definition televis
2、ion systems (1990-1993) Q. ITU-R 78-1/10 The ITU Radiocommunication Assembly, considering a) that there is a requirement to transmit more than one sound signal including stereophony with a television picture; b) that within a television channel as used in present systems several sound channels could
3、 be accommodated; c) that the use of some of these additional possibilities could necessitate changes to the present television standards; d) that changes affecting existing transmissions can only be introduced if compatibility with existing receivers, at least during a sufficiently long transition
4、period, is retained; e) that a prerequisite of a new system is that the sound signals should serve at least the same coverage area as the vision signal; f) that a new system could also provide for the transmission of sound programmes, independent from the picture, or in place of a television picture
5、; g) that the technical quality of the sound transmission can be improved; h) that the improvements in picture quality associated with high-definition and enhanced definition television may warrant examination of the sound system needed to keep in step with the higher level of realism available in t
6、he picture, decides that the following Question should be studied 1 What are the unified standards for the transmission of several sound signals to be incorporated in one television channel (see Note 1) in terrestrial or satellite broadcasting including the use of digital modulation and the case whe
7、re some of those sound signals are to be integrated into the video waveform? NOTE 1 In this context the term “unified” implies that the standards to be defined should as far as practicable apply both to terrestrial and to satellite broadcasting. NOTE 2 See Recommendation ITU-R BS.707, further decides 1 that the results of the above studies should be included in (a) Recommendation(s); 2 that the above studies should be completed by 2005. _
