Power control for D2D communication underlaying cellular networks based on deep Q-learning and fractional frequency reuse

This paper considers device-to-device (D2D) communication underlaying cellular networks, where frequency resources are shared between D2D users and cellular users. When D2D users reuse the frequency resources occupied by the cellular users, interference could be produced among the two kinds of users. By means of the fractional frequency reuse approach, a traversal frequency reuse scheme is proposed, in which central D2D users in each cell reuse the frequency bands for neighbouring edge cellular users in sequence according to a counterclockwise direction. The proposed reuse scheme effectively minimizes the number of intra-cell interference links, leading to an improvement of the average sum rate. Subsequently, based on the proposed traversal reuse strategy, a deep Q-learning algorithm is implemented for power control. Simulation results demonstrate that the proposed power control algorithm outperforms other traditional methods in terms of sum rate.