大规模天线SWIPT的安全速率性能分析

摘要

In the multi-drop broadcast system,the existing research is to optimize the single-user security rate in the complete channel state information.In fact,it's impossible that there exists only one user in the system.The base station often receives incomplete channel state information.Aiming at this problem,a robust beamforming scheme was proposed.In the multi-user case,considering the influence of channel estimation error on the system security rate,the particle swarm optimization algorithm was used to optimize the emission beamforming vector,artificial noise covariance and power split ratio to ensure that the user collects a certain energy while maximizing the safe transmission rate.The simulation results show that the proposed scheme is slightly lower than the security rate in the ideal case,but it is meaningful to the actual system,taking into account the existence of eavesdropping users and the estimation error.%多入单出广播系统中,现有研究均是在完整信道状态信息下来优化单用户安全速率,而实际上,系统中不可能只存在一个用户,基站往往接收到的也是不完整信道状态信息.针对此问题,提出了一种顽健性波束成形方案.在多用户情况下,考虑信道估计误差对系统安全速率的影响,采用粒子群算法来联合优化发射波束成形矢量、人工噪声协方差和功率分流比,从而在确保用户收集一定能量的同时最大化安全传输速率.仿真结果表明,所提方案相对于理想情况下的安全速率略微降低,但考虑到存在窃听用户和估计误差的情况,对实际系统具有指导意义.