美军卫星通信系统的发展及其技术研究

随着信息技术的快速发展,美军为满足未来战争需要不断地规划研发新的通信卫星系统。文中主要讨论了美军卫星通信系统的现状和未来发展,归纳了相关的关键技术,最后总结了目前卫星通信的重要性并指出了今后研究的方向。研究美军在这一领域的新发展和成果,目的是为我国构建空间信息网络奠定必要的基础。     

美军E频段通信技术发展述评

美国国防高级研究计划局(Defense Advanced Research Projects Agency,DARPA)采用E频段通信,设计、建立并验证了移动设备与机载平台间的自组织、可扩展的数据回传网络及稳健的、大容量骨干网络。对美军E频段通信的发展情况进行了梳理,针对“移动热点”与“100 Gb/s”两个典型项目从应用场景、性能指标、进度安排、关键技术等方面进行了分析,最后给出了对我国相关领域技术创新的启示与思考。     

Who Makes U.S. Government Policy in World Communications?

Fragmentation among government agencies strengthens the already large role of private industry and makes it difficult to inform the public of the "crisis" ahead.     

美国电话回叫技术的发展

本文介绍了电话回收技术的起因，运作方式和发展情况，分析了这种技术对国际长途电话业务带来的影响，并举例说明了一些国家就此采取的相关策略。     

U.S. Television Programs in the International Market: Unfair Pricing?

A microeconomic analysis demonstrates that the low level of prices charged by the United States when exporting expensive-to-produce drama is attributable to the low incremental cost of supplying additional copies of programs to other countries rather than to "damping" or any other unfair pricing practice.     

美国数字战略的演进与发展

20世纪90年代以来,全球信息技术飞速发展.作为信息技术的重要创新者和引领者,美国政府从克林顿时期即开始实施以"国家信息高速公路"为代表的一系列重大战略,对支持和促进数字技术和数字经济发展发挥重要作用.本文对美国政府的数字战略进行系统梳理,从发展历程、主要举措、实施路径等多方面分析美国联邦政府数字战略的主要特点,以期有...     

美国军事卫星通信系统发展研究

美国的军事卫星通信系统结构复杂、功能先进、造价不菲,它们代表了当今军事卫星通信系统的最高水平和最新发展趋势。随着宽带、窄带、抗毁三个系列通信卫星的陆续发射,美国军事卫星通信系统的作战能力也在逐步形成,同时,美军还引入商业卫星通信系统作为补充。文中主要介绍了美国军事卫星通信系统的发展现状、面临的问题,及其未来在探索解聚的卫星通信体系结构、引入软件可重新编程栽荷技术,以及提高商业卫星通信系统的可靠性等方面的发展方向。     

The U.S. filings for multimedia satellites: a review

The United States Federal Communications Commission (FCC), in response to industry pressure, has conducted four Notice of Proposed Rule Making (NPRM) sessions in which companies could apply for licenses for satellite systems operating at new frequencies (Ka‐ or Q/V‐band) or in new, non‐geostationary orbits at Ku‐band. The first NPRM resulted in the award, in May 1997, of licenses for 13 systems operating at Ka‐band. Of these, seven propose to offer global or near‐global service. The FCC opened a second window for companies to file for Ka‐band systems, which closed in December 1997 and resulted in nine additional filings, seven of which are for global systems. Thus far, none of these systems have been licensed. In parallel with the second Ka‐band window was one for systems operating at still higher frequencies, in the Q‐ and V‐bands. This resulted in 16 filings, 14 of which are for global systems. Still more recently (January 1999), the FCC concluded an NPRM for non‐geostationary satellite systems operating at Ku‐band. Applications were filed for six systems—all intended for global service. Nearly all of the above systems are intended to serve small offices and consumers by providing broadband services such as multimedia distribution and Internet access. The proposed global systems are reviewed, and the technical approaches taken to provide this type of service at low cost to the user are discussed. Fielding any of the global systems entails significant technical challenges and a large degree of business risk. This seems likely to hamper efforts to raise capital and may defer the completion of any of the systems beyond their announced dates of initial operation (2001–2003). Copyright © 2000 John Wiley & Sons, Ltd.     

U.S. Global telecommunications: The popcorn principle

The telecommunications policies of the United States have mostly been spearheaded through the “Free Market Philosophy.” The Federal Communications Commission has been most influential in leading this effort. This philosophy has permeated U.S. international telecommunications, and its effects are producing interesting results worldwide.     

美军航天测控企业级地面体系的发展

美国军事航天地面测控系统采用为每种军事卫星系统配套专用测控系统的方式构建,形成"烟囱"式割裂的格局,造成资源和人力的极大浪费.空间威胁的日益严峻迫使美军进行地面系统的转型.美军提出构建"企业地面体系"(EGA),用通用的测控系统完成所有军事卫星的测控,通过云技术提高网络安全性,通过自动化和商业化减少操作人员,提高系统效率,降低运维成本,腾出更多人力完成有效载荷的部署与操控,以应对日益迫近的太空作战.虽然美军EGA的具体方案还未出台,但通过对其发展背景、总体设想、拟采用的关键技术及发展现状进行跟踪分析,总结了美军构建通用军事测控系统的总体设计思路及设计原则,对我国航天测控系统的发展提出了建议.