UAV-D2D Assisted Latency Minimization and Load Balancing in Mobile Edge Computing with Deep Reinforcement Learning

Now Unmanned Aerial Vehicle (UAV) with Mobile Edge Computing (MEC) severs and Device-to-Device (D2D) communications provide offload computing services for User Devices (UDs). However, the UAV has relatively high transmission latency. And D2D lacks the necessary flexibility. In this paper, we introduce a novel MEC system that utilizes the collaborative advantages of flexible movement of UAV and the low latency transmission of D2D communication to process tasks from UDs. We formulate an optimization problem focused on minimizing the tasks transmission and execution delay of UDs. The problem involves joint optimization of user scheduling, UAV trajectory, and resource allocation of Virtual Machines (VMs) on the MEC server. To tackle this non-convex problem, we propose a Deep Reinforcement Learning (DRL) algorithm with Deep Deterministic Policy Gradient (DDPG). Through simulation results, we demonstrate that DDPG reduces the latency by 41% compared to Deep Q-Network (DQN) and Actor-Critic (AC) algorithm. Our collaborative UAV-D2D model has 16% and 32% lower latency than when only the UAV or D2D works alone.