Hand-Gesture Sensing Using Four Sequential Quadrature Channel (FSQC) Calibration With MIMO-FMCW Radar

This article presents a radar-based position-tracking system for contactless hand-gesture recognition using a 60-GHz multiple-input–multiple-output (MIMO) frequency-modulated continuous-wave (FMCW) radar with an L-shaped 2T4R antenna array. To address noise interference and limited spatial resolution, a sequential signal-processing framework is proposed, integrating a four sequential quadrature channel (FSQC) calibration method to mitigate phase errors and an extended virtual element (VE) method to improve angular resolution and reduce sidelobe interference. Simulation results confirm the effectiveness of the FSQC calibration in combination with the VE method for accurate position detection. Experimental results further demonstrate the ability of the system to accurately reconstruct complex trajectory patterns, including digits, geometric shapes, Japanese Hiragana, and multistroke Chinese characters. These findings highlight the potential of the proposed framework for human–machine interaction (HMI) applications requiring robust hand-gesture recognition.