基于IRS辅助的SWIPT物联网系统安全波束成形设计

为满足绿色万物互联的智能信号处理部署和物理层安全的新要求,针对基于智能反射面辅助的无线携能通信物联网系统中可持续能量供应紧缺问题,提出了一种安全波束成形设计方法。考虑保密速率、发射功率和IRS反射相移约束,以最大化能量采集器采集功率为目标,联合优化基站发射波束成形矩阵和干扰机协方差矩阵以及IRS相移,将优化问题建模为具有二次型约束的非凸二次型规划问题。利用松弛变量、半定松弛法、辅助变量和序列参数凸逼近法将非凸的二次型问题转化为等价的凸问题,并提出一种交替迭代优化算法获取原问题的可行解。仿真结果表明,所提算法能够快速收敛,且与基准方案相比能有效地提升性能。

Secure beamforming design for IRS-assisted SWIPT Internet of things system

In order to meet the new requirements of intelligent signal processing deployment and physical layer security for green interconnection of things,a design method of secure beamforming was proposed to solve the problem of the shortage of sustainable energy supply in the information and energy transmission at the same time Internet of things(IoT)system assisted by intelligent reflecting surface(IRS).Considering the constraints of secrecy rate,transmit power and IRS reflection phase shift,the optimization problem was modeled as a non-convex quadratic programming problem with quadratic constraints,aiming at maximizing the acquisition power of energy collector,and jointly optimizing the base station transmit beamforming matrix,jammer covariance matrix and IRS phase shift.The non-convex quadratic problem was transformed into an equivalent convex problem by using the relaxation variable,semidefinite relaxation method,auxiliary variable and sequence parameter convex approximation method,and an alternative iterative optimization algorithm was proposed to obtain the feasible solution of the original problem.Simulation results show that the proposed algorithm can converge quickly and improve performance effectively compared with the benchmark scheme.