Joint Radio Map Construction and Dissemination in MEC Networks: A Deep Reinforcement Learning Approach

With the development of 6G, the rapidly increasing number of smart devices deployed in the Industrial Internet of Things (IIoT) environment has been witnessed. The radio environment is showing a trend of complexity, and spectrum conflicts are becoming increasingly acute. User equipment (UE) can accurately sense and utilize spectrum resources through radio map (RM). However, the construction and dissemination of RM incur a heavy computational burden and large dissemination delay, which limit the real-time sensing of spatial spectrum situations. In this paper, we propose an RM construction and dissemination method based on deep reinforcement learning (DRL) in the context of mobile edge computing (MEC) networks. We formulate the dissemination modes selection and resource allocation problems during RM construction and dissemination as a mixed-integer nonlinear programming problem. Then, we propose an actor-critic-based joint offloading and resource allocation (ACJORA) algorithm for intelligent scheduling of computational offloading and resource allocation. We design a novel weighted loss function for the actor network, which combines the discrete actions for offloading decisions and the continuous actions for resource allocation. And the simulation results show that the proposed algorithm can reduce the cost of dissemination by optimizing the offloading strategies and resources, which is more applicable for real-time RM applications in MEC networks.