共查询到19条相似文献,搜索用时 109 毫秒
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李洪力刘安斐窦晓晶刘京 《无线电工程》2020,(3):219-226
随着导航战的推进,卫星导航系统面临严峻的电磁干扰问题。地面站作为卫星导航系统的核心部分,负责整个系统导航业务的运行管理,其是否受到电磁干扰是制约系统稳定运行的关键因素。在综合考虑满足卫星导航RDSS业务和RNSS业务干扰监测与定位需求基础上,对地面站干扰监测与定位系统进行了总体设计和RDSS入站干扰监测与定位分系统、RNSS地面站场区干扰监测与定位分系统设计,实现了RDSS业务入站信号和地面站场区附近复杂电磁环境的干扰监测与定位,解决了系统无干扰监测与定位手段的问题,为干扰源排查与消除提供了有效支撑,最大程度地减小了干扰对系统的影响,确保了系统安全稳定运行。 相似文献
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随着卫星通信和卫星广播业务发展的要求,大量的卫星地面站急需兴建。建站过程中对卫星地面站站址选择的电测工作是不可缺少的步骤之一,而对电测系统灵敏度的要求计算是测试当中的一个重要项目。 相似文献
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采用卫星仿真工具包对全球卫星导航系统包括GPS、Galileo、Compass等导航卫星星座的地面站天线方位、俯仰跟踪特性进行了仿真分析,以大口径地面接收天线为例讨论了可行的地面站天线座架形式和跟踪体制.并综合常规卫星通信抛物面天线精度分析方法和测控雷达天线的精度分析方法对跟踪精度进行了系统的分析,分析结果可作为今后类... 相似文献
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VSAT卫星地面站在建站之前及建站之后,怀疑卫星信号遭受地面信号干扰时,需要对站址周围的电磁环境进行测试,以便确定地面站周围可能存在的干扰信号频率、强度、方向等数据,判定其是否对卫星信号构成影响,进而采取措施减小或避免干扰的发生。 相似文献
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多通道卫星导航系统专用测试设备是一种多功能、高精度、高可靠性的卫星导航系统专用测试设备。本文详细论述了该设备的研制思路、技术方案、系统组成和创新点等,重点对其软硬件设计进行了分析。 相似文献
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提出了对双系统组合定位的增强方法,详细研讨了双卫星导航增强系统方案。该方法提高了卫星导航系统信息的安全性,在特殊时期,在某一系统不能使用时(如GPS),仍能利用其它卫星导航系统提供定位服务;通过地面差分修正站播发双卫星导航系统之间的系统时差以及地面差分修正站视界内所有卫星的伪距修正量,提高了卫星导航设备的可用性和定位精度;同时增加了信号的完好性,提供的冗余信息增加,使接收机自主完好性监测(RAIM)方法更易鉴别出故障卫星。 相似文献
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提出了一种集成设计导航定位与数传通信的差分导航通信系统,以满足无人机对机载轻量化高精度导航定位的需求。该差分导航通信系统由地面站和机载设备组成:地面站完成差分卫导修正量生成与播发;机载设备接收地面站播发的差分卫导修正量,并结合本地卫导观测量实现高精度的实时动态定位。系统试验结果表明,该差分导航通信系统在50 km范围内具备亚米级精度的导航能力。 相似文献
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An operational orbit determination (OD) and prediction system for the geostationary Communication, Ocean, and Meteorological Satellite (COMS) mission requires accurate satellite positioning knowledge to accomplish image navigation registration on the ground. Ranging and tracking data from a single ground station is used for COMS OD in normal operation. However, the orbital longitude of the COMS is so close to that of satellite tracking sites that geometric singularity affects observability. A method to solve the azimuth bias of a single station in singularity is to periodically apply an estimated azimuth bias using the ranging and tracking data of two stations. Velocity increments of a wheel offloading maneuver which is performed twice a day are fixed by planned values without considering maneuver efficiency during OD. Using only single‐station data with the correction of the azimuth bias, OD can achieve three‐sigma position accuracy on the order of 1.5 km root‐sum‐square. 相似文献
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J. C. Camparo R. P. Frueholz A. P. Dubin 《International Journal of Satellite Communications and Networking》1997,15(3):135-139
Satellite navigation and communication systems often require precise synchronization among spacecraft clocks. In the traditional method for achieving synchronization, a ground station makes time-offset measurements to the various spacecraft clocks, and then updates the time and frequency of each satellite as needed. Though straightforward in its implementation, disadvantages to the traditional approach include the large workload placed on the ground station, the need for multiple ground stations to view satellites in different geosynchronous positions, and unaccounted-for delays in atmospheric propagation. In early 1996 Milstar became the first satellite system to employ crosslinks for precise satellite time synchronization. At that time, the crystal oscillator clock onboard FLT-1, the first Milstar satellite, had its time and frequency tied (i.e., slaved) to the rubidium (Rb) atomic clock carried onboard FLT-2, the second Milstar satellite. The FLT-2 Rb atomic clock was controlled by the ground, while the slaving of FLT-1 to FLT-2 was accomplished without ground intervention: all timing information required by the slaving algorithm was obtained through the FLT-1 to FLT-2 satellite crosslink. In this paper we will first show the timekeeping capabilities of the two satellite clocks when operating independently, which indicate that both clocks are performing well. Then, we will present ground station measurements of FLT-1 and FLT-2 timekeeping that demonstrate satellite synchronization to better than 150 nsec without ground intervention. As satellites are added to the Milstar constellation, crosslink slaving will minimize ground station timekeeping activities, thereby lowering system operating costs. © 1997 John Wiley & Sons, Ltd. 相似文献
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