1、Op. ITU-R 51 OPINION ITU-R 5 1 * 1 STUDY OF DIGITAL TECHNIQUES BY CCIR STUDY GROUPS AND THE CMTT (1974) The CCIR, CONSIDERING (a) 11 and the CMTT: that the study of digital techniques will be an important part of the future work of CCIR Study Groups 4, 9, 10, (6) by CCITT; that CCITT Study Group XVI
2、II has been assigned all questions relating to pulse-code modulation under study (e) that CCITT Study Group XVIII will establish performance requirements for transmission systems and, for this work, will need to know the likely digit rates for the various services to be carried by digital networks a
3、nd performance capabilities of various transmission media, including terrestrial radio and satellite systems, IS UNANIMOUSLY OF THE OPINION 1. that the work of CCIR Study Groups 4 and 9 on digital transmission systems should be closely coordinated with the work of CCITT Study Group XVIII. The Direct
4、or, CCIR, should transmit the relevant documents of Study Groups 4 and 9 directly to CCITT Study Group XVIII; 2. that Study Groups 10 and 11 should study the methods of digital encoding and error protection appropriate to the broadcasting, recording and studio processing of sound programme and telev
5、ision signals respectively, and to study methods for the reduction of redundancy in these signals; 3. that the CMTT should study the methods of digital encoding, transcoding and error protection appropriate to the long distance transmission of sound programme and television signals. The CMTT should
6、also provide the necessary coordination to ensure that the work of Study Groups 10,ll and the CMTT is transmitted to CCITT Study Group XVIII in a unified manner through the Director, CCIR; 4. concerned through the Director, CCIR. that the results of the work of CCITT Study Group XVIII should be transmitted to the CCIR Study Groups * The Director, CCIR, is requested to bring this Opinion to the attention of the IEC and the CCITT.
