导航星座网络路由算法研究  

Performance evaluation of routing algorithms in navigation constellation networks

作　　者：李子璇 严志博 赵康僆[1] 李文峰[1] Li Zixuan;Yan Zhibo;Zhao Kanglian;Li Wenfeng(School of electronic science and engineering,Nanjing University,Nanjing,210093,China)

机构地区：[1]南京大学电子科学与工程学院,南京210093

出　　处：《南京大学学报（自然科学版）》2018年第3期529-537,共9页Journal of Nanjing University（Natural Science）

基　　金：国家自然科学基金(61401194);中央高校基本科研专项资金(021014380064);江苏高校优势学科建设工程

摘　　要：导航星座网络具有拓扑动态变化,物理链路间断可用,时延较长,信道误码率较大,以及星间链路资源与星上处理资源有限等特点.在导航星座网络中,实际传输的数据流量种类多样,且往往分布不均.其链路调度一般都是事先规划好的,具有可预测性和周期性,相较一般的卫星通信网络,具有更强的规律性.如何应对导航星座网络中的各种问题并利用导航星座网络的独特特性,实现数据的高效传输,选用合适的路由算法十分关键.目前,针对卫星网络的路由算法多数基于通信卫星星座来开展研究,针对带有指向性天线分时隙通信的导航星座网络的算法不太多,对已提出的几种具有代表性的空间路由算法进行分析,并选取最短时延下最少跳数路由和连接图路由进行重点研究,通过OPNET(Optimized Network Engineering Tool)对路由机制的性能进行仿真评估,得出有关导航星座网络中路由算法的适用性准则,为导航星座网络中路由算法的设计和选用提供参考.Constellation network of Global Navigation Satellite System（GNSS）is characterized by particular features,such as dynamic topology,intermittent usability of physical link,long propagation delay,high bit error rate of channel,limited onboard processing capabilities,and restricted inter-satellite link resources.In navigation constellation network,different types of traffic are required to be transferred according to a variety of demands.The traffic distribution tends to imbalance under practical circumstances.Beyond that,Navigation constellation network topology has strong predictability and periodicity,on account of its strict and deterministic inter-satellite link scheduling.Compared to conventional satellite communication networks,it presents more distinct regularity.To make the best use of limited resources and attain the overall efficient transmission of data,it is critical to deploy an appropriate routing algorithm,dealing with all these challenges and exploiting characteristics particularly possessed by GNSS.So far,magnitude routing algorithms have been issued,mainly focused on satellite communication networks,while not many are particularly aimed at GNSS with time slot allocation of crosslinks equipped with directional antennas.Therefore,this paper targets at above-mentioned navigation constellation network with specific topological features and takes an analysis of several relevant and typical routing algorithms.Then route of minimum number of hops of the least delay and contact graph routing（CGR）are selected to be further studied,of which the performances are evaluated in different scenarios built by network simulation software optimized network engineering tool（OPNET）.End-to-end delay and routing calculations are chosen to be the two standards for assessment.Finally,some criterions about the applicability of routing algorithms in navigation constellation network are drawn,which can be good references to the adoption or development of the efficient routing algorithms in GNSS.

关 键 词：导航星座网络 路由算法 OPNET 端到端时延 路由计算次数 

分 类 号：V474.25[航空宇航科学与技术—飞行器设计]