Human Target Identification via De-Cluttered RAI and MIMO FMCW Radar.

Frequency-modulated continuous wave (FMCW) radar systems offer unique motion-oriented attributes that contribute to the remote identification of human targets. Employing the time-division multiplexing (TDM) technique, fast-time samples from a virtual receiver array are converted into a 2D complex-valued range-angle image (RAI) using a 2D fast Fourier transform (FFT). While the human chest wall induces a significant phase alteration over consecutive radar chirps in the FMCW radar setup, stationary clutter exhibits a nearly constant phase throughout the coherent processing interval (CPI). This study utilizes an advanced 77-GHz multiple-input and multiple-output (MIMO) FMCW radar system and applies a DC-value suppression technique along the slow-time axis. This technique aims to develop a stationary-clutter-free RAI, enhancing the identification of human targets. This approach’s key advantage lies in its high precision and low computational complexity, making it well-suited for real-time applications. The performed experiments and graphical representations effectively underscore the applicability of this method in complex environments. In comparison with analogous research works, a significant reduction of approximately 58% in the average execution time is observed.