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CCITT第十六研究组1977—1980研究期共有13个研究课题,先后召开过四次会议。末期会议于1980年3月27、28、31日在日内瓦召开。会议讨论了本研究期研究课题的进展情况和取得的成果,对有关建议提出了修改补充意见和新的建议草案,讨论了下一研究期需要继续研究的课题。现分课题扼要介绍如下。 课题1 电话交换网路中电路、交换和连接的传输特性 本课题研究:a)参考当量(包括相对电平、传输衰减);b)假设参考连接;c)串话;d)衰减和群时延失真等的现有建议是否需要修改。主要结果是: (1)关于参考当量:为了更加集中地引出与相对电平概念有关的定义,将G.141A.6节及其相应的注1转
CCITT Sixteenth Study Group 1977-1980 A total of 13 research projects during the study period, has held four meetings. The final meeting was held in Geneva on March 27, 28 and March 31, 1980. The meeting discussed the progress of the research project and the achievements made during the study period, proposed amendments to the relevant proposals and draft new proposals, and discussed the topics for further study in the next study period. The sub-topics are briefly described below. Topic 1 Transmission Characteristics of Circuit, Switching and Connection in Telephone Switching Network This research project: a) reference equivalent (including relative level and transmission attenuation); b) hypothetical reference connection; c) crosstalk; d) attenuation and group time Whether existing recommendations such as derogation need revision. The main results are: (1) With regard to the reference equivalence: In order to derive a more focused definition of the relative level concept, G.141A.6 and its corresponding note 1