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移动通信与3G 移曲通信的最终目标是实现无线个人通信(Wireless Personal Communications),即利用各种网络和通信手段最终实现任何人在任何时间、任何地点与任何人进行任何形式的信息交换。目前移动通信已经发展到了第二代。第一代蜂窝移动通信系统是模拟系统,采用频分多址技术,如AMPS和TACS等系统,其容量较小。第二代移动通信系统为数字系统,采用TDMA和窄带CDMA(IS95 1.25Mhz)方案。如目前普遍应用的欧洲的GSM系统、英国的DCS-1800、北美的D-AMPS(IS54/IS136)、日本的PDC和北美的CDMA(IS95)。第二代系统主要以语音业务为主,可以提
The ultimate goal of mobile communications and 3G mobile communications is to achieve Wireless Personal Communications, which uses a variety of networks and communications to ultimately enable anyone to exchange any form of information with anyone, anytime, anywhere. At present, mobile communication has been developed to the second generation. The first generation of cellular mobile communication system is an analog system, using frequency division multiple access technology, such as AMPS and TACS systems, its smaller capacity. The second generation of mobile communication system is a digital system, using TDMA and narrowband CDMA (IS95 1.25Mhz) program. Such as GSM systems currently in use in Europe, DCS-1800 in the United Kingdom, D-AMPS (IS54 / IS136) in North America, PDC in Japan and CDMA (IS95) in North America. The second generation of the main voice-based systems business, you can mention