无蜂窝大规模MIMO系统中基于DDPG的接入点选择算法  

DDPG-Based Access Point Selection in Cell-Free Massive MIMO System

作　　者：王鑫丽 徐瑨 孙梦颖 陶小峰[1] WANG Xinli;XU Jin;SUN Mengying;TAO Xiaofeng(School of Information and Communication Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,China)

机构地区：[1]北京邮电大学信息与通信工程学院,北京100876

出　　处：《北京邮电大学学报》2025年第1期1-6,13,共7页Journal of Beijing University of Posts and Telecommunications

基　　金：中央高校基本科研业务费专项项目(2242022K60006)。

摘　　要：为避免无蜂窝大规模多输入多输出(MIMO)前传链路过载,提出了接入点选择的优化问题,以最大化前传链路使用效率。首先,构建平均链路频谱效率用于衡量前传链路使用效率;其次,建立最大化平均链路频谱效率同时满足用户服务质量需求的目标问题;然后,考虑到目标问题的非凸性和优化变量的不可微性,传统优化算法求解较为困难,提出一种基于深度确定性策略梯度(DDPG)的动态接入点选择算法;最后,优化DDPG的输出,使其适用于接入点选择的离散性动作。仿真结果表明,所提算法能有效地提升系统的平均链路频谱效率并满足用户的服务质量需求。To avoid the overload of fronthaul links in cell-free massive multiple input multiple output(MIMO)system,an optimization problem for access point selection is formulated to maximize the fronthaul link usage efficiency.Firstly,the average spectral efficiency per-link is constructed to measure the utilization efficiency of the fronthaul link.Secondly,the objective problem of maximizing the average spectral efficiency per-link while meeting users'quality of service requirements is established.Then,considering the non-convexity of the objective problem and the non-differentiability of the optimization variables,which makes it challenging for traditional optimization algorithms to find solutions,a dynamic access point selection algorithm based on deep deterministic policy gradient(DDPG)is proposed.Finally,the output of the DDPG is refined to ensure compatibility with the discrete nature of access point selection actions.Simulation results show that the proposed algorithm can effectively enhance the average spectral efficiency per link of the system and meet the quality of service requirements.

关 键 词：大规模多输入多输出 无蜂窝网络架构 接入点选择 深度确定性策略梯度 

分 类 号：TN929.5[电子电信—通信与信息系统]