4D Spectral-Scanning FMCW LiDAR System for 360-Degree Detection

Light detection and ranging (LiDAR), an important sensing technology, is widely accepted in numerous areas. To realize a better environmental perception, increasing demands emerge for LiDAR systems with higher resolution, larger field of view (FoV), and the capability to detect more information. In this paper, a frequency-modulated continuous-wave (FMCW) LiDAR system combining ultrafast spectral scanning and rotating scanning enables a simultaneous ranging and velocity measurement with an angular resolution of 0.0900° × 0.0320° and a wide FoV of 360° × 1.60°. The velocity measurement deviation is 0.968 mm/s for a target moving at a speed of 15.6 mm/s. Spectral scanning utilizing a frequency-swept vertical-cavity surface-emitting laser (VCSEL) and a grating, enables an adaptive vertical FoV and angular resolutions. Simultaneous ranging and velocity measurement for every pixel along the spectral scanning line can be achieved within a single scan, facilitating high-speed vertical scanning. This 4D FMCW LiDAR system with a compact and low-cost structure can realize accurate detection of the environment, enhancing the performance of existing LiDAR systems, and promising to assist in accurate point cloud segmentation and convenient detection for autonomous robots, further extending the application of LiDAR.