Polarization Sensitive Array Based Physical-Layer Security

TL;DR

This paper introduces a polarization sensitive array framework to enhance physical-layer security in wireless communications by leveraging polarization differences to improve secrecy rates, especially in challenging environments.

Contribution

It develops new PLA-based secure beamforming algorithms for point-to-point and relaying networks, including robust schemes under channel uncertainties.

Findings

PLA-based algorithms reduce power consumption.

They improve secrecy rates compared to scalar array designs.

Performance is robust under pointing errors.

Abstract

We propose a comprehensive framework exploiting the polarization sensitive array (PLA) to improve the physical layer security of wireless communications. More specifically, the polarization difference among signals is utilized to improve the secrecy rate of wireless communications, especially when these signals are spatially indistinguishable. We firstly investigate the PLA based secure communications for point-to-point wireless systems from the perspectives of both total power minimization and secrecy rate maximization. We then take a step further to apply the PLA based secure beamforming designs to relaying networks. The secrecy rate maximization for relaying networks is discussed in detail under both the perfect channel state information and the polarization sensitive array pointing error. In the later case, a robust scheme to achieve secure communications for relaying networks is proposed. Simulation results show that the proposed PLA based algorithms achieve lower total power consumption and better security performance compared with the conventional scalar array designs, especially under challenging environments where all received signals at destination are difficult to be distinguished from the spatial domain.