导航星座星间链路设计研究-导航、制导与控制专业毕业论文.docx

摘 要
导航卫星的星间链路技术是提高导航卫星星座系统生存能力的一个重要方面,卫星的不断运动会使卫星之间的链路距离不断发生变化,从而导致卫星可见性的变化,这对星间链路的选择带来了一定的挑战。
本文旨在建立和完善导航卫星星座星间链路的体系,研究具有同轨及异轨星间链路的星座网络,根据星座结构设计合理的链路方案,用较短的时延和较小的切换建立星座的星间链路用于测距和通信,对星间链路的理论和方法进行仿真分析,最终实现导航卫星间的互通互联,组成星间信息网,保证导航星座的全连通。主要的研究工作如下:
1、系统研究了导航星座星间链路的基础理论,对星间链路的频段选择作了说明,并介绍了星间链路的分类以及构建星间链路的条件和方法。
2、针对分布式处理和集中式处理两种信息处理方式的特点,本文选取了集中式处理方式, 在星座中选取一颗卫星作为主星。主星具有处理数据的能力,计算工作量大,从星负责转发和测距。
3、分析了最短路径算法和 K 短路径算法这两种链路选择方案各自存在的优缺点,提出了链路优化方案。
4、以 GPS 星座中的卫星作为星间链路的仿真对象,并以 IGS 精密星历作为仿真数据,用 Matlab 语言仿真验证本文所提方案具有时延和切换都较小的优点,评估链路维持时间等性能, 并对三种方案进行比较,证明链路优化方案的可行性。
5、对导航卫星天线的多波束情况进行了分析,研究了星间链路的可用性,用三种方案对三波束、四波束、五波束和六波束天线情况进行了仿真。
关键词:导航星座,星间链路,星座网络,链路算法,天线波束
Abstract
The technology of inter satellite links between navigation satellites is an important aspect to improve the survival ability of the navigation satellite constellation system. Constant movements of the satellites in the constellation make the distance between satellites changes constantly and cause visibility change. The choice of inter satellite links is met by a challenge from it.
This article aims to establish and perfect the system of inter satellite links and research the navigation work which has links in the same or different orbital planes. Then design reasonable link schemes according to the constellation structure, establish inter satellite links in a relatively shorter period of time delay and less switching for ranging munication, analysis the theory and method of inter satellite links, and finally realize the connection between satellites pose work to guarantee full connectivity in the navigation constellation. The main researches are as follows:
1、The basic theories of inter satellite links in the navigation constellation are systematically
expounded, including band selection, the classification of the links and methods of link construction.
2、Introduce the features of distributed processing mode and centralized processing mode, this article selects the centralized processing approach. Sel