Multi-IRS-Aided Doppler-Tolerant Wideband DFRC System

• Published in: IEEE transactions on communications Vol. 71; no. 11; p. 1
• Main Authors: Wei, Tong, Wu, Linlong, Mishra, Kumar Vijay, Bhavani Shankar, M. R.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.11.2023; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Algorithms; Beamforming; Broadband; Clutter; Dinkelbach algorithm; dual-function radar-communications; intelligent reflecting surfaces; Interference; Line of sight communication; MIMO communication; Moving targets; Narrowband; Optimization; Parameter estimation; Radar; Radar detection; Receivers; Signal to noise ratio; Target detection; Wideband; wideband beamforming
• ISSN: 0090-6778; 1558-0857
• DOI: 10.1109/TCOMM.2023.3305466

Intelligent reflecting surface (IRS) is recognized as an enabler of future dual-function radar-communications (DFRC) by improving spectral efficiency, coverage, parameter estimation, and interference suppression. Prior studies on IRS-aided DFRC focus either on narrowband processing, single-IRS deployment, static targets, non-clutter scenario, or on the under-utilized line-of-sight (LoS) and non-line-of-sight (NLoS) paths. In this paper, we address the aforementioned shortcomings by optimizing a wideband DFRC system comprising multiple IRSs and a dual-function base station that jointly processes the LoS and NLoS wideband multi-carrier signals to improve both the communications SINR and the radar SINR in the presence of a moving target and clutter. We formulate the transmit, receive and IRS beamformer design as the maximization of the worst-case radar signal-to-interference-plus-noise ratio (SINR) subject to transmit power and communications SINR. We tackle this nonconvex problem under the alternating optimization framework, where the subproblems are solved by a combination of Dinkelbach algorithm, consensus alternating direction method of multipliers, and Riemannian steepest decent. Our numerical experiments show that the proposed multi-IRS-aided wideband DFRC provides over 4 dB radar SINR and 31.7% improvement in target detection over a single-IRS system.