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一、前言随着汽车电话的普及。通信容量不可避免地要增大,为此,日本电电公司横须贺电气通信研究所研制了大容量通信系统,大容量系统和中容量系统的不同之处在于①信道间隔窄带化,从现有的25kHz减少到12.5kH;②采用分集接收技;③缩小区域半径,从现在的标准5公里缩短到3公里。该系统还将使用能和现有的中容量系统基地台相连接、且具有可兼容服务功能和性能的车载移动机(其大小在1000cm~3以下)及可装拆式/便携式移动机(其
First, the preface With the popularity of car phones. Therefore, the Yokosuka Electric Communication Research Institute of Nippon Electric Company has developed a large-capacity communication system. The difference between a large-capacity system and a medium-capacity system is that narrowing of the channel spacing, from the existing 25kHz reduced to 12.5kH; (2) the use of diversity reception technology; (3) reduce the radius of the region, from the current standard 5 km shortened to 3 km. The system will also use on-board mobile machines that are capable of interfacing with existing mid-capacity system base stations and that have compatible service features and capabilities, with sizes below 1000cm-3, and removable / mobile machines,