Energy-Efficient Optimization for Physical Layer Security in Multi-Antenna Downlink Networks with QoS Guarantee

TL;DR

This paper proposes an energy-efficient power allocation scheme for multi-antenna downlink networks that enhances physical layer security while ensuring QoS, balancing secrecy, efficiency, and delay constraints.

Contribution

It introduces a novel energy-efficient power allocation method combining switched beamforming with security and QoS considerations in multi-antenna networks.

Findings

The proposed scheme maximizes secrecy energy efficiency under delay and power constraints.

Numerical results confirm the effectiveness of the energy-efficient power allocation.

The method improves secure communication performance with energy savings.

Abstract

In this letter, we consider a multi-antenna downlink network where a secure user (SU) coexists with a passive eavesdropper. There are two design requirements for such a network. First, the information should be transferred in a secret and efficient manner. Second, the quality of service (QoS), i.e. delay sensitivity, should be take into consideration to satisfy the demands of real-time wireless services. In order to fulfill the two requirements, we combine the physical layer security technique based on switched beam beamforming with an energy-efficient power allocation. The problem is formulated as the maximization of the secrecy energy efficiency subject to delay and power constraints. By solving the optimization problem, we derive an energy-efficient power allocation scheme. Numerical results validate the effectiveness of the proposed scheme.