Joint Transmit and Reflective Beamformer Design for Secure Estimation in IRS-Aided WSNs

TL;DR

This paper introduces a joint transmit and reflective beamformer design using IRS technology to enhance secure parameter estimation in wireless sensor networks, effectively reducing eavesdropping risks.

Contribution

It proposes a novel SDR-based iterative algorithm for joint beamforming, optimizing security and estimation accuracy in IRS-assisted WSNs.

Findings

Achieves lower MSE in parameter estimation.

Enhances security against eavesdropping.

Demonstrates robustness through simulations.

Abstract

Wireless sensor networks (WSNs) are vulnerable to eavesdropping as the sensor nodes (SNs) communicate over an open radio channel. Intelligent reflecting surface (IRS) technology can be leveraged for physical layer security in WSNs. In this paper, we propose a joint transmit and reflective beamformer (JTRB) design for secure parameter estimation at the fusion center (FC) in the presence of an eavesdropper (ED) in a WSN. We develop a semidefinite relaxation (SDR)-based iterative algorithm, which alternately yields the transmit beamformer at each SN and the corresponding reflection phases at the IRS, to achieve the minimum mean-squared error (MSE) parameter estimate at the FC, subject to transmit power and ED signal-to-noise ratio constraints. Our simulation results demonstrate robust MSE and security performance of the proposed IRS-based JTRB technique.