低轨卫星网络动态路径切换技术

面向星座式低轨（LEO）卫星网络，针对动态路由技术重构时间长导致的资源利用率下降问题，提出了一种基于预测的路径切换机制.依据卫星飞行轨迹，预测星间链路的可用时间，从而判断当前传输路径的可用寿命.在当前路径断开之前及时触发路由重构，为当前传输寻找备用路径，避免路由重构导致传输中断.提出了新型路径选择方案，根据当前路径代价和网络全局负载状态设计了综合代价函数，用于选择最优路径.仿真结果表明，所提出的路径切换技术可有效降低数据转发的丢包率，提升网络整体吞吐量.

Dynamic Path Switching Technology for LEO Satellite Networks

For constellation low earth orbit (LEO) satellite networks, aiming at the problem of resource utilization decline caused by long reconfiguration time of dynamic routing technology, a path switching mechanism based on prediction is proposed. According to the satellite flight trajectory, the duration of inter-satellite link is predicted, so the available lifetime of the current transmission path can be estimated. With the proposed routing strategy, the route reconfiguration is initiated in time before the current path is disconnected, therefore. The transmission interruption by changing to another newly established path can be avoided. Moreover, according to the current path cost and the global load state of the network, a path cost metric is designed to select an optimal path. Simulations show that the proposed routing scheme can effectively reduce the packet loss rate of data forwarding and improve the overall throughput of the network.