Efficient Topology Design for LEO Mega-Constellation Using Topological Structure Units with Heterogeneous ISLs.

Area of Science:

• Space Systems Engineering
• Satellite Communication Networks
• Network Topology Design

Background:

• Global mega-constellations are rapidly expanding due to advancements in launch vehicles and satellite production.
• Inter-satellite networking is crucial for enhancing constellation performance and effectiveness.
• Existing research inadequately addresses topological structure design and engineering challenges of inter-orbit Inter-Satellite Links (ISLs).

Purpose of the Study:

• To propose a novel heterogeneous Inter-Satellite Link (ISL) topology architecture for mega-constellations.
• To develop algorithms for designing efficient ISL topological structures considering practical engineering constraints.
• To optimize constellation performance by reducing end-to-end delay and Inter-Satellite Link hops.

Main Methods:

• Proposed a heterogeneous ISL topology: stable intra-orbit laser backbone + dynamic inter-orbit radio network.
• Defined optimization objectives for mega-constellation topological design, proving the problem is NP-hard.
• Introduced Topological Structure Units (TSUs) and a reuse strategy for simplified design.
• Developed TSU-based and regional TSU-based heterogeneous ISL topological design algorithms.

Main Results:

• Simulation experiments in Starlink and GW constellation scenarios validated the proposed algorithms.
• Demonstrated significant reductions in end-to-end delay compared to existing approaches.
• Showcased a decrease in the number of Inter-Satellite Link hops required for data transmission.

Conclusions:

• The proposed heterogeneous ISL topology architecture and associated algorithms are effective for mega-constellations.
• The approach successfully addresses engineering challenges and optimizes constellation performance.
• This work provides a practical framework for designing efficient and high-performing satellite networks.