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目前,我国公众无线移动通信网经历了第一代模拟移动通信、第二代数字移动通信,正在跨进第三代多媒体移动通信时代的大门,而无线移动通信的对讲机却一直停留在模拟通信阶段,不仅功能单一,而且频率利用率不高,早已不能满足各行各业对通信的要求。因此,研发生产新一代支持话音、
At present, China’s public wireless mobile communications network has experienced the first generation of analog mobile communications, the second generation of digital mobile communications, is entering the door of the third generation of multimedia mobile communications era, and wireless mobile communications walkie-talkie has been stuck in the analog communications phase , Not only a single function, and the frequency of utilization is not high, has long been unable to meet the communication requirements of all walks of life. Therefore, research and development to produce a new generation of support voice,