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作 者:张煦
出 处:《电信快报》1998年第8期3-6,共4页Telecommunications Information
摘 要:主要说明无线通信将应用于移动通信、个人通信和全球通信。数字蜂窝网将增设微蜂窝区 ,频率从 90 0MHz升至 1 .8~ 2GHz ,向宽带和多媒体方向发展 ,数据速率从 1 44kb /s升至 2Mb /s。手机将是TDMA /CDMA双模。蜂窝网不仅用于移动通信 ,而且用于固定用户的市内接入网。卫星通信将加快发展低轨道 /中轨道卫星通信网 ,而同步卫星仍需利用。移动卫星网可通电话 ,可进行多媒体通信 ,速率为 2Mb /s,并通过地面信关站 ,与陆地固定通信网结合一起 ,实现全球个人通信。The paper briefly describes the rapid development of wireless applications to the mobile,personal,and global communication services.The digital cellular network would be expanded to microcellular,with frequency band raised from 900MHz to 2 GHz,and ultimately toward wide band and multimedia communication,with data rate raised from 144kb /s to 2 Mb /s.The handset may be of dual mode,for use either with TDMA or with CDMA.The cellular principle may also be applied to fixed subscribers through wireless local access network.New development of satellite communication would be emphasized on the satellite networks of low /medium earth orbit planes in addition to the traditional geosynchronous earth orbit.The mobile satellite communication is not only for telephone,but also for multimedia,with bit rate of 2 Mb /s.Through the gateway stations on the earth,mobile satellite network and terrestrial fixed network would be integrated,to realize the global personal communication.
分 类 号:TN927.2[电子电信—通信与信息系统]
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