Efficient Optimization-based Routing Strategies for Large-Scale Multi-Layer LEO Satellite Networks

The rapid evolution of telecommunications technology underscores the vast potential of Low-Earth Orbit (LEO) satellite networks as a complement to traditional terrestrial systems, effectively addressing their inherent limitations. Nonetheless, LEO networks encounter formidable challenges. The high-velocity movement of satellites frequently leads to service disruptions, necessitating swift and adaptive rerouting mechanisms. Moreover, routing decisions must satisfy multiple constraints to ensure Quality of Service (QoS) and system reliability. These challenges are further intensified by the complexity of large-scale, multi-layer satellite constellations. To overcome these issues, this study formulates a multi-constrained optimization model. The integration of node-splitting techniques and multi-path routing strategies serves to simplify network topology and enhance overall reliability. Two efficient routing algorithms are introduced: the Optimization-based Routing Algorithm (OBRA) and the α-based Heuristic (H-AB). Computational evaluations reveal that OBRA achieves superior QoS optimization, while H-AB demonstrates significant advantages in computational efficiency. Both algorithms are capable of delivering real-time solutions, even within networks comprising up to 10,000 satellites. This work contributes to the advancement of routing methodologies for large-scale, multi-layer LEO satellite networks and supports the development of future 6G communication systems.