This paper addresses the emerging practical requirement that wireless information and power transfer are employed simultaneously in a multiple-input single-output (MISO) secrecy channel. Transmit beamforming without artificial noise and that with artificial noise are considered. In addition, perfect and imperfect channel state information of both the legitimate receivers and eavesdroppers are investigated. These four scenarios correspond to four optimization problems. The considered problems aim to maximize the secrecy rate with constraints on the transmit power and the harvested energy at each receiver. Since these optimization problems are nonconvex, we propose the efficient algorithms based on Difference of Convex (DC) functions programming and DC Algorithm (DCA )—an innovative approach in nonconvex optimization. Exploiting the special structure of these problems, we utilize the semidefinite relaxation technique and S-procedure to reformulate them as general DC programs. The efficient algorithms based on general DCA are developed to solve the corresponding general DC programs. Numerical results are presented which illustrate the effectiveness of our proposed algorithms, they outperform the existing approaches in terms of both quality and rapidity.

本文提出了在多输入单输出（MISO）保密通道中同时采用无线信息和功率传输的新兴实用要求。考虑没有人为噪声和有人为噪声的发射波束成形。另外，还研究了合法接收者和窃听者的完美和不完美的信道状态信息。这四种情况对应于四个优化问题。所考虑的问题旨在最大化保密率，同时限制每个接收器的发射功率和所收集的能量。由于这些优化问题是非凸的，因此我们提出了基于凸差（DC）函数编程和DC算法（DCA）的高效算法，这是非凸优化的一种创新方法。利用这些问题的特殊结构，我们利用半定松弛技术和S过程将它们重新构造为一般的DC程序。开发了基于通用DCA的高效算法来求解相应的通用DC程序。数值结果表明了我们提出的算法的有效性，它们在质量和快速性方面都优于现有方法。