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一、问题的提出近十几年来,全晶体管化的地下同轴电缆载波通信设备已和微波中继通信一道,成为世界各国国内通信的骨干.为满足数传、电视等业务的需要,地下同轴电缆载波设备的容量,已从300路发展到10800路.由于传输容量的增长,导致了增音段距离的缩短,按照C.C.I.T.T.建议的原则,话路数每增加3倍,增音段长度应减少一半.所以大容量10800路设备的增音段长度只有1.5公
First, the issue put forward Over the past decade, all transistor-based underground coaxial carrier communication equipment and microwave relay communications have become the backbone of all countries in the world communications.To meet the needs of data transmission, television and other services, underground with The capacity of the axis cable carrier device has been developed from 300 to 10800. Due to the increase of transmission capacity, the distance between the segments is shortened. According to the principle of CCITT, the length of the segment should be increased by 3 times each Reduce by half.Therefore, the capacity of 10800 high-capacity devices only has a length of 1.5 kilometers