Super-Resolution and Accurate Full-Field Displacement Measurement With Millimeter-Wave Radars

Millimeter-wave radar-based full-field displacement measurements are of significant interest in many applications due to their advantages in remote sensing and adaptability to harsh environments. Direct interferometry could provide a solution for full-field displacement measurement. However, due to the commonly low azimuth resolution of millimeter-wave radar, direct interferometry falls short of meeting the resolution and accuracy requirement of full-field displacement measurement. In this article, we propose the cumulative imaging and decoupling tracking (CIDT) method, which can accurately measure full-field displacements of adjacent targets spaced below resolution. The CIDT method leverages on a cumulative imaging strategy that enables stable target location determination with super-resolution (SR) and fixed estimation operators that robustly extract the displacements with high accuracy. The fixed estimation operator based on the prior assumption of micro motion means that the solved target locations are consistent at different times, thus preventing distortions caused by non-convexity in conventional SR algorithms. Simulation and experimental validations are provided to demonstrate the effectiveness and performance of the proposed method. The proposed method shows application prospects in millimeter-wave full-field displacement measurement in diverse fields.