This paper investigates a secure wireless-powered sensor network (WPSN) with the aid of a cooperative jammer (CJ). A power station (PS) wirelessly charges for a user equipment (UE) and the CJ to securely transmit information to an access point (AP) in the presence of multiple eavesdroppers. Also, the CJ are deployed, which can introduce more interference to degrade the performance of the malicious eavesdroppers. In order to improve the secure performance, we formulate an optimization problem for maximizing the secrecy rate at the AP to jointly design the secure beamformer and the energy time allocation. Since the formulated problem is not convex, we first propose a global optimal solution which employs the semidefinite programming (SDP) relaxation. Also, the tightness of the SDP relaxed solution is evaluated. In addition, we investigate a worst-case scenario, where the energy time allocation is achieved in a closed form. Finally, numerical results are presented to confirm effectiveness of the proposed scheme in comparison to the benchmark scheme.

中文翻译：

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物联网的保密无线供电传感器网络

本文借助协作干扰器（CJ）研究了安全的无线传感器网络（WPSN）。电站（PS）在存在多个窃听者的情况下为用户设备（UE）和CJ无线充电，以安全地将信息传输到接入点（AP）。此外，还部署了CJ，这可能会引入更多干扰，从而降低恶意窃听者的性能。为了提高安全性能，我们提出了一个优化问题，以最大化AP的保密率，从而共同设计安全波束形成器和能量时间分配。由于提出的问题不是凸的，因此我们首先提出一种采用半定规划（SDP）松弛的全局最优解。此外，还评估了SDP松弛解决方案的紧密度。此外，我们研究了最坏的情况，即以封闭形式实现能源时间分配。最后，给出了数值结果，以确认与基准方案相比，该方案的有效性。