Low-Complexity Super-Resolution Signature Estimation of XL-MIMO FMCW Radar

TL;DR

This paper introduces a low-complexity super-resolution method for target signature estimation in XL-MIMO FMCW radars affected by the spatial wideband effect, enabling real-time high-resolution sensing.

Contribution

It proposes a novel 2D compressive sensing-based approach specifically designed to handle the spatial wideband effect in XL-MIMO FMCW radars, improving estimation accuracy and computational efficiency.

Findings

Outperforms existing narrowband and wideband techniques in simulations

Achieves high-resolution target signatures with low computational complexity

Suitable for real-time large-scale radar applications

Abstract

Extremely Large-Scale (XL) multiple input multiple output (MIMO) antenna systems combined with ultra-wide signal bandwidth (BW) offer the potential for ultra-high-resolution sensing in frequency modulated continuous wave (FMCW) radars. However, the use of ultra-wide BW results in significant spatial delays across the array aperture, comparable to the range resolution, leading to the spatial wideband effect (SWE). SWE introduces coupling between the range and angle domains, rendering conventional narrowband signal processing techniques ineffective for target signature estimation. In this paper, we propose an efficient super-resolution signature estimation technique for XL-MIMO FMCW radars operating under SWE, leveraging compressive sensing (CS) methods. The proposed 2D CS-based approach offers low computational complexity, making it highly suitable for real-time applications in large-scale radar systems. Numerical simulation results validate the superior performance of the proposed method compared to existing wideband and narrowband estimation techniques.