Inter-Satellite Links-Enabled Cooperative Satellite Edge Computing

Satellite edge computing (SEC) has become a research hotspot in academia because of its enormous potential to enhance the performance of satellite communication systems, increase data processing capabilities, and address the growing data demand. However, ground users are typically unevenly distributed. When the data processing demand in a particular area suddenly surges, one satellite connected to these users may not have adequate computing capabilities to process a large amount of data simultaneously, resulting in a drop in edge computing system performance. This paper considers the possibility of inter-satellite cooperation, where a satellite directly connected to the ground user equipment (UE) not only offloads UE's task but also transmits partial tasks to other satellites via an inter-satellite link for cooperative offloading. In particular, offloading tasks through inter-satellite cooperation can alleviate the computational burden in areas with high traffic distribution. We consider computing resources and task partition to minimize the system weighted-sum energy consumption. In this study, we employ a rigorous methodology. Specifically, we develop an iterative algorithm by decomposing the original non-convex problem into several sub-problems. Each sub-problem is then transformed into a convex problem and solved by the Lagrange dual method, ensuring the robustness of our approach. Simulation results demonstrate that our scheme can efficiently utilize satellite computing resources.