摘 要：文章研究了智能反射面辅助的无线供能空中计算系统。其中，接入点通常在 IRS 的辅助下，经下行链路为多个传感器进行无线能量传输，然后经上行链路进行空中计算。首先刻画了满足传感器能量收集约束条件下的系统计算速率的最大化问题，通过对传输时隙长度、接入点的发送波束赋形矩阵和接收波束向量，以及 IRS 在上下行链路中的波束赋形矩阵进行联合优化，仿真结果显示，所设计的系统和求解算法性能要远远好于基准方案。
关键词：无线供能系统；空中计算；凸优化；智能反射面；无线能量传输
DOI:10.19850/j.cnki.2096-4706.2021.04.012
中图分类号：TN929.5 文献标识码：A 文章编号：2096-4706（2021）04-0048-05
Research on Wireless Powered Over-the-air Computation System Assisted by Intelligent Reflecting Surface
MA Ganggang
（School of Information Engineering，Guangdong University of Technology，Guangzhou 510006，China）
Abstract：This paper studies the wireless powered over-the-air computation system assisted by intelligent reflecting surface （IRS）. With the assistance of IRS，access points usually transmit wireless energy for multiple sensors via downlink，and then perform computation via uplink. Firstly，the problem of maximizing the system computation rate under the constraint of sensor energy collection is described. The transmission time slot length，the transmit beamforming matrix and the receive beamforming vector of the access point， and the beamforming matrix of the IRS in the uplink and downlink are jointly optimized，the performance of the designed system and algorithm is much better than that of the benchmark schemes.
Keywords：wireless powered system；over-the-air computation；convex optimization；intelligent reflecting surface；wireless power transfer
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作者简介：马刚刚（1993—），男，汉族，河南沁阳人，博士 在读，研究方向：无线能量传输，无线通信，凸优化理论在无线通 信中的应用。