Joint Optimization of Transmission and Computation Resources for Rechargeable Multi-Access Edge Computing Networks

Multi-access edge computing (MEC) and wireless power transfer (WPT) have emerged as promising paradigms to address the bottlenecks of computing power and battery capacity of mobile devices. In this paper, we investigate the integrated scheduling of WPT and task offloading in a rechargeable multi-access edge computing network (RMECN). Specifically, we focus on exploring the tradeoff between energy efficiency, buffer stability, and battery level stability in the RMECN to obtain reasonable scheduling. In addition, we adopt a dynamic Li-ion battery model to describe the charge/discharge characteristics. Given the stochastic nature of channel states and task arrivals, we formulate a stochastic optimization problem that minimizes system energy consumption while ensuring buffer and battery level stability. In this problem, we jointly consider offloading decisions, local central processing unit (CPU) frequency, transmission power, and current of charge/discharge as optimization variables. To solve this stochastic non-convex problem, we first transform it into an online optimization problem using the Lyapunov optimization theory. Then, we propose a distributed algorithm based on game theory to overcome the excessive computation and time consumption of traditional centralized optimization algorithms. The numerical results demonstrate that the proposed tradeoff scheme and corresponding algorithm can effectively reduce the system's energy consumption while ensuring the stability of buffer and battery level.