Joint Flexible Duplexing and Power Allocation with Deep Reinforcement Learning in Cell-Free Massive MIMO System  

作　　者：Danhao Deng Chaowei Wang Zhi Zhang Lihua Li Weidong Wang 

机构地区：[1]School of Electronic Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,China [2]School of Information and Communication Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,China [3]Key Laboratory of Universal Wireless Communications,Ministry of Education,Beijing University of Posts and Telecommunications,Beijing 100876,China

出　　处：《China Communications》2023年第4期73-85,共13页中国通信（英文版）

基　　金：supported by the National Key R&D Program of China under Grant 2020YFB1807204;the BUPT Excellent Ph.D.Students Foundation under Grant CX2022306。

摘　　要：Network-assisted full duplex(NAFD)cellfree(CF)massive MIMO has drawn increasing attention in 6G evolvement.In this paper,we build an NAFD CF system in which the users and access points(APs)can flexibly select their duplex modes to increase the link spectral efficiency.Then we formulate a joint flexible duplexing and power allocation problem to balance the user fairness and system spectral efficiency.We further transform the problem into a probability optimization to accommodate the shortterm communications.In contrast with the instant performance optimization,the probability optimization belongs to a sequential decision making problem,and thus we reformulate it as a Markov Decision Process(MDP).We utilizes deep reinforcement learning(DRL)algorithm to search the solution from a large state-action space,and propose an asynchronous advantage actor-critic(A3C)-based scheme to reduce the chance of converging to the suboptimal policy.Simulation results demonstrate that the A3C-based scheme is superior to the baseline schemes in term of the complexity,accumulated log spectral efficiency,and stability.

关 键 词：cell-free massive MIMO flexible duplexing sum fair spectral efficiency deep reinforcement learning asynchronous advantage actor-critic 

分 类 号：TN929.5[电子电信—通信与信息系统] TP18[电子电信—信息与通信工程]