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美国航宇局最近请求联邦通信委员会批准建立大型移动卫星通信系统,为地面运行中的车辆和移动用户提供无线电和电话通信业务,以便把UHF波段的移动通信服务扩展到广大农村地区。所谓陆地移动通信就是为行驶中的车辆提供无线电广播和电话通信服务。据航宇局的研究表明,在现有的技术条件下,现有陆地移动通信设施只能为城市服务,根本无法为居住在美国318个标准都市区之外的5710万人提供移动电话服务。航宇局经调查发现,如果在这部分人口中的0.5％要求提供移动电话服务,将会得到拥有285,500个用户的
NASA recently asked the Federal Communications Commission to approve the establishment of a large mobile satellite communications system to provide radio and telephone communications services to ground-based vehicles and mobile subscribers to extend UHF mobile communications services to vast rural areas. The so-called land mobile communications provide radio broadcasting and telephony services to moving vehicles. According to NASA’s research, under the existing technical conditions, the existing land mobile telecommunications facilities can only serve the urban areas and it is impossible to provide mobile phone services to 57.1 million people living outside the 318 standard metro areas in the United States. NASA’s investigation found that if 0.5% of this population is required to provide mobile phone services, it will receive 285,500 users