Joint Power Splitting and Secure Beamforming Design in the Wireless-powered Untrusted Relay Networks

TL;DR

This paper proposes a joint design of power splitting and secure beamforming in wireless-powered untrusted relay networks, utilizing artificial noise to enhance secrecy and energy efficiency, with algorithms balancing optimality and computational complexity.

Contribution

It introduces a novel joint design framework leveraging artificial noise for energy and secrecy, with algorithms that improve performance and reduce computation in untrusted relay networks.

Findings

LOA achieves comparable secrecy rates to GOA with less computation.

Artificial noise enhances both energy harvesting and secrecy.

Simulation confirms effectiveness of the proposed algorithms.

Abstract

In this work, we maximize the secrecy rate of the wireless-powered untrusted relay network by jointly designing power splitting (PS) ratio and relay beamforming with the proposed global optimal algorithm (GOA) and local optimal algorithm (LOA). Different from the literature, artificial noise (AN) sent by the destination not only degrades the channel condition of the eavesdropper to improve the secrecy rate, but also becomes a new source of energy powering the untrusted relay based on PS. Hence, it is of high economic benefits and efficiency to take advantage of AN compared with the literature. Simulation results show that LOA can achieve satisfactory secrecy rate performance compared with that of GOA, but with less computation time.