保密MIMO无线携能系统的鲁棒能效优化

针对多输入多输出无线携能系统，研究了在多个窃听者存在且其信道状态信息不准确情况下的保密能量效率优化问题．在最大发射功率和最小收获能量的约束条件下，通过联合设计波束成形矩阵、辅助噪声方差矩阵和功率分配比，最大化系统最差情况的保密能量效率．基于分式理论，将原来的非凸分式问题转换成易处理的减式形式．通过S-procedure和一阶泰勒级数展开，将难于处理的非凸问题转化为凸问题．在此基础上提出了基于Dinkelbach方法的两级优化迭代算法，仿真结果验证了该算法的有效性和收敛性．

Robust energy efficiency optimization for secrecy MIMO systems with SWIPT

This paper investigates the secrecy energy efficiency optimization for simultaneous wireless information and power transfer in the multiple-input-multiple-output wiretapping system which consists of multiple eavesdroppers (Eves). In the presence of imperfect channel estimation ,the beamforming matrix, the artificial noise covariance matrix and the power splitting ratio are jointly designed to maximize the worst-case secrecy energy efficiency under the maximum transmit power and the minimum harvested energy constraints. Due to the non-convexity of this problem, the objective function is recast into an equivalent parametric problem by exploiting the fractional programming theory, and then the non-convex equivalent problem is approximated as a convex optimization problem by means of the S-Procedure and first order Taylor series expansion. Furthermore, a two level optimization iterative algorithm is proposed based on the Dinkelbach method. Finally, simulation results are provided to show the effectiveness and convergence of the proposed algorithm.