TCDS: A Time-Relevant Graph Based Topology Control in Triple-Layer Satellite Networks

In a triple-layer satellite (TLS) network with GEO, MEO and LEO, maintaining connectivity of topology confronts the challenge of intermittent visibility due to periodically orbital motions of nodes. To address this issue, in this letter, we develop a time-relevant graph called as space-time graph (STG) model for depicting the topological structure with fine granularity, by taking into account time-domain and spatial-domain properties. With STG, a Time-evolving Connected Dominating Set (TCDS) algorithm is proposed to construct a backbone network for efficient topology control with high spatial and temporal accessibility of the triple-layer network. The simulation results demonstrate better efficiency of the proposed algorithm with respects to the average hop and connectivity probability, compared with time-evolving multi-layered clustering (TEMC) algorithm and single time-slot clustering (STC) algorithm.