基于低轨移动星座的高速星载路由器设计

High speed onboard router based on LEO constellation

随着地面网络流量不断增长,实现星地一体化要求星间网络能够提供基于IP的大流量数据传输。而星载路由器作为连通星间网络的关键设备,其转发速率和服务质量等指标决定了整个星间网络的吞吐量和时效性。考虑到现有星载路由器吞吐量低的现状,提出一种适用于低轨移动通信星座的高速星载路由器设计方案,在基于拓扑快照的路由基础上补充3层动态路由,在保证交换速率的同时减少网络故障导致的丢包,实现"一次路由,多次交换"。采用共享内存式的交换存储单元,利用Spacewire和Serdes高速接口单元,理论上星间数据吞吐量能够达到最高5.1 Gbit/s,且支持IP数据传输,为与地面网络的融合奠定基础。

With the explosion of the internet traffic, the IP-based large volume data transmission provided by satellite network becomes a prerequisite to integrate satellite network and terrestrial network. On-board router,whose transmission rate and QoS(Quality of Service) determine the throughput and efficiency of the entire network,is the key facility of the satellite network. Based on the low throughput of existing onboard routers, a design of high speed on-board router for LEO(Low Earth Orbit) satellite constellation is proposed. Implementing dynamic routing into the snapshot-based routing scheme makes it possible to minimize packet drop when link failure happens. This scheme enables iterative data switching after one time route computing. By using shared-memory mode to build switching-memory unit, also with Spacewire and Serdes interface units deployment, the inter-satellite throughput can achieve up to 5.1 Gbit/s in theory. Moreover, the onboard router supports IP-based transmission, which lays the foundation for integrating with terrestrial network.