1、C:DOCUMENTS AND SETTINGSQGV33745MY DOCUMENTSDOWNLOADSR-QUE-SG06.29-2002-MSW-E.DOC 22.10.03 15.07.10 QUESTION ITU-R 29/6 Transmission of supplementary information with a single transmitter in frequency-modulation sound broadcasting (1990-2002) Q. ITU-R 71/10 The ITU Radiocommunication Assembly, consi
2、dering a) that the broadcasting with a single transmitter of information supplementary to the sound programmes is technically feasible, particularly through the use of digital signals modulating a sub-carrier; b) that the use of many types of supplementary information for various applications can be
3、 foreseen; c) that the transmission of such information with no direct relationship to the main programme can be accomplished by such techniques; d) that it is desirable to encourage development of compatible or possibly common systems; e) that Recommendation ITU-R BS.643 specifies a “system for aut
4、omating tuning and other applications in FM radio receivers for use with the pilot tone system”, decides that the following Question should be studied 1 What are the applications that can be envisaged? 2 What are the minimum demands on the transmission channel for these applications, e.g. informatio
5、n rate, access time, coverage compared with that of the monophonic service, acceptable loss- and error-ratios? 3 What are the possibilities of using the same transmission channel for future applications? 4 What transmission systems satisfy the preceding minimum demands, in particular, what is the fr
6、equency of sub-carrier, type of modulation, information rate, digital frame structure, error-detecting and/or correcting systems, sensitivity to the content of the main programme and to the reception conditions? 5 What compatibility with existing broadcasting services can be achieved? 6 What informa
7、tion and method of presentation of some of the undefined groups in an RDS system can be recommended with regard to applications such as text and graphic transmission? NOTE 1 See Recommendations ITU-R BS.643, ITU-R BS.1194 and ITU-R BS.1350, further decides 1 that the results of the above studies should be addressed to: update and complement Recommendations ITU-R BS.643 and ITU-R BS.1350; prepare (a) new Recommendation(s); - 2 - 6/1-E C:DOCUMENTS AND SETTINGSQGV33745MY DOCUMENTSDOWNLOADSR-QUE-SG06.29-2002-MSW-E.DOC 22.10.03 15.07.10 2 that the above studies should be completed by 2005. _
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