LEO Mega-Constellations Routing Algorithm Based on Area Segmentation.

Low earth orbit (LEO) mega-constellations in future 6G have attracted the attention from both academia and industry. However, due to the high dynamic characteristic of the LEO satellite network topology and the limited on-board resources, existing approaches relying on high on-board processing capabilities and monitoring the global network state, result in intolerable packet loss rate and excessive signalling overhead. In this paper, a routing algorithm based on area segmentation for LEO mega-constellations is proposed according to the topological characteristics of the network. Specifically, we divide the LEO mega-constellations into multiple areas with four quadrant parts. In addition, the transmission cluster is defined consisted of two adjacent parts based on transmission direction. With the relative geographical location and transmission clusters, we joint intra-area and inter-area routing to realize multi-path routing and forwarding by periodically updating the link state, instead of globally calculating. Simulation results demonstrate that the proposed algorithm can achieve higher throughput, decrease the packet loss rate by 22% and reduce the signalling overhead significantly.