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该文回顾了国际移动卫星组织航空卫星通信系统的发展历史,对其航空卫星通信系统的组成及应用作了概括介绍。 相似文献
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国外海军卫星通信系统发展综述 总被引:1,自引:0,他引:1
文章全面介绍了西方主要国家的海军卫星通信系统的发展及其应用历程.重点叙述了几个现役的和在研的通信卫星系统和应用情况,并对其海军卫星通信系统的未来发展方向进行了探讨。 相似文献
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卫星通信和星上抗干扰技术 总被引:1,自引:0,他引:1
首先回顾了卫星通信和抗干扰技术的发展历史及其原因,然后对卫星通信系统的组成作了简单介绍,最后介绍了现阶段星上抗干扰的主要技术手段、扩频体制目前遇到的问题及其解决办法,并重点介绍了直扩体制下抗窄带干扰的两种主要方法。 相似文献
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文章针对无星际链路的低轨卫星通信系统,利用OPNET软件设计了低轨卫星通信系统在透明转发模式下的核心网构成,并进行了性能仿真。首先介绍核心网的构成、功能和拓扑,在此基础上实现了呼叫处理和切换的仿真,统计了呼叫时延、切换时延等性能指标,分析了仿真结果,为低轨道卫星通信系统的设计奠定了一定的参考价值。 相似文献
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外军卫星通信的发展与启示 总被引:1,自引:0,他引:1
介绍外军卫星通信在信息化战争中的重要地位和作用;外军卫星通信系统(DSCD-Ⅲ、Milstar)、战场态势卫星通信系统(GBS)和军事小卫星通信系统(MacSat)等系统的现状和技术发展趋势;卫星通信技术发展的几点启示。 相似文献
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简要介绍了卫星通信系统面临的几种干扰威胁以及各种干扰的威胁程度,简单介绍了一些抗干扰技术,最后重点介绍了一种综合抗干扰系统,它利用跳频技术和智能天线技术来提高系统的抗干扰能力。 相似文献
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介绍日本新型的8字形卫星通信系统的设计和应用,内容包括卫星轨道设计、移动卫星通信构成、地球站构成、与同步卫星在国定卫星通信中的频率共享、基于卫星的定位系统、极区地球观测。 相似文献
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简述了卫星通信系统及其组成与作用,论述了星上通信分系统的测试与方法,分析和介绍了部分相关卫星通信标准以及我国卫星通信标准体系的建立情况,并提出了建议。 相似文献
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为满足越来越高的航天任务要求,卫星系统必须具有一定程度自主性;但自主卫星系统是复杂系统,研究困难,仿真往往成为唯一的有效手段.本文提出使用基于agent的建模与仿真(ABMS)方法研究自主卫星系统的策略.首先分析了3个有代表性的自主航天任务系统,然后详细讨论了卫星系统的自主性,最后介绍了作者独立开发的支持自主卫星系统ABMS的模型体系结构和软件平台--ABSSA和absimlib,为仿真研究自主卫星系统提供了理论和实践支持. 相似文献
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Wolfgang Keydel 《Acta Astronautica》1984,11(1):3-14
(Possibilities and Limitations of Microwave Systems for Satellite Remote Sensing)—Microwaves are applied in satellite remote sensing in both active, i.e. radar systems and in passive, i.e. microwave radiometer systems. The advantages and disadvantages of active and passive microwave systems in comparison to each other and to optical systems are discussed shortly. It becomes evident that radar has advantages over microwave radiometry due to its ranging and velocity-measurement capability, due to its SAR-capability with its extremely fine resolution and due to the fact that no major theoretical limitations exist for the obtainable measurement accuracy.The most important radar systems for Earth and ocean observations from satellites are altimeter, scatterometer and imaging radars with real or synthetic aperture. The physical and technical basics of these types of radar are presented together with some applications. Examples for remote sensing data and results obtained from different microwave remote sensing systems show the present state of the art and the present possibilities and limitations of microwave systems for satellite remote sensing. 相似文献
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Theoretical and experimental aspects of design of service devices and systems using burning and explosion energy to separate automatic spacecraft constructions are considered. The main dependences necessary for their calculation are presented. The areas of rational application of one or another type of separation devices are determined, and the results of ground tests of separation systems are given. The practical recommendations on designing the described systems for separation of high-precision automatic spacecraft for planetary and astrophysical investigations are presented. 相似文献
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In the history of human space exploration, many failures of launch vehicles and spacecraft tare caused by vibration. At first, the periods in which the space products are in a vibration environment are discussed and the need for vibration testing is then introduced. As the main content of this paper, the current situation of shaker systems is elaborated in detail. In this part, electrodynamic shakers, as the most widely used vibration generators, are illustrated in detail including structures, principles and performances. Special inventions worldwide in the development of electrodynamic shakers such as induction ring shakers, high force shakers, multi-axial vibration testing systems and combined environmental testing systems are presented. At last, the recent progress and outlook of shaker systems are summarized. 相似文献