低轨卫星星座通信系统星间路径选择

Choosing inter-satellite paths in the LEO satellite constellation network

现有的低轨卫星星座路由算法在选择星间路径时,根据算法特征分别选用最短传输延时路径(LDP)和最小跳数路径(LHP),但是对选用LHP的合理性缺乏详细分析。针对低轨卫星星座系统中LDP与LHP的关系问题,该文通过遍历仿真验证,LDP属于LHP集合,且LHP集合中各条路径传输延时差别不大,可以用LHP代替LDP以降低计算复杂度,便于路由算法的分布式实现。此外,基于LHP传输延时的变化特征,提出了星间路径选择的策略,减少了路由切换次数,为进一步优化分布式路由算法奠定了基础。

Routing algorithms for low earth orbit （LEO） satellite constellation networks select the least delay path （LDP） or the least hop path （LHP） according to the algorithm＇s characteristic, but the rationality of choosing the LHP has not been proven in detail. This work focuses on the relationship between LDP and LHP in the LEO satellite network. Traversal simulations show that the LDP belongs to the LHP set in the LEO network and that the delay variation in the LHP set is acceptable. Therefore, the LHP criterion can be used instead of the LDP criterion to reduce the computational complexity and achieve a distributed approach. The transmission delay characteristics of the LHP are used to choose an inter-satellite path to reduce handover costs. The results show how to optimize the distributed routing algorithm in the LEO satellite network.