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

• Published in: IEEE signal processing letters Vol. 29; pp. 692 - 696
• Main Authors: Ahmed, Mohammad Faisal, Rajput, Kunwar Pritiraj, Venkategowda, Naveen K. D., Mishra, Kumar Vijay, Jagannatham, Aditya K.
• Format: Journal Article
• Language: English
• Published: New York IEEE 2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Beamforming; Design parameters; Eavesdropping; Electronic mail; IRS; Iterative algorithms; Jamming; non-convex optimization; Optimization; Parameter estimation; Physical layer security; Receivers; Signal to noise ratio; Wireless sensor networks
• ISSN: 1070-9908; 1558-2361; 1558-2361
• DOI: 10.1109/LSP.2022.3147139

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 letter, 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.