Multiagent Reinforcement Learning for Task Offloading of Space/Aerial-Assisted Edge Computing

Abstract

The task offloading in space-aerial-ground integrated network (SAGIN) has been envisioned as a challenging issue. In this paper, we investigate a space/aerial-assisted edge computing network architecture considering whether to take advantage of edge server mounted on the unmanned aerial vehicle and satellite for task offloading or not. By optimizing the energy consumption and completion delay, we formulate a NP-hard and non-convex optimization problem to minimize the computation cost, limited by the computation capacity and energy availability constraints. By formulating the problem as a Markov decision process (MDP), we propose a multiagent deep reinforcement learning (MADRL)-based scheme to obtain the optimal task offloading policies considering dynamic computation request and stochastic time-varying channel conditions, while ensuring the quality-of-service requirements. Finally, simulation results demonstrate the task offloading scheme learned from our proposed algorithm that can substantially reduce the average cost as compared to the other three single agent deep reinforcement learning schemes.