High‐Resolution Non‐Line‐of‐Sight Tracking By Comb‐Calibrated FMCW LiDAR

Abstract Non‐line‐of‐sight (NLOS) tracking has the ability to detect and locate moving objects which are hidden from the direct line of sight. It has a number of potential applications in autonomous driving, security and search‐and‐rescue scenarios. The current approaches for NLOS tracking mostly rely on time‐of‐flight (ToF) LiDAR, mmWave radar or RGB camera. However, they may either have a limited resolution or need accumulation to detect the position and velocity. Here a real‐time comb‐calibrated frequency‐modulated‐continuous‐wave (FMCW) LiDAR system is proposed and demonstrated for high‐resolution NLOS tracking. A 3D positioning (and velocity) accuracy of 2 mm (and 2 mm s −1 ) and the capability to realize real‐time multi‐object tracking are demonstrated in experiment. Importantly, the FMCW‐LiDAR approach can obtain the position and velocity of multiple objects in a snapshot , thus resolving the problems of measurement origin uncertainty, false alarm, and detection overlap in multi‐target tracking. The proposed approach shows significant potential for practical applications in NLOS detection and sensing.