High-resolution LiDAR using random modulated continuous wave with a low code rate
Junya Wang, Gaofei Zhang, Zheng You
Abstract
Light detection and ranging (LiDAR) is essential to improving the reliability of autopilot technology. In this paper, we propose a new laser-ranging method for three-dimensional micro-electro-mechanical system LiDAR. First, a mathematical model is presented and the analytical solution for real-time calculation derived. Then, the mixed M-sequence and data code modulates the laser diode by pulse amplitude modulation. Finally, the resolution is enhanced by the matched filter and delay-locked loop technique, lowering the requirement of the code rate and analog-to-digital-converter sampling rate. Analytical and experimental results demonstrate that a distance precision of less than 2 cm and acquisition time within 8 ns (125 MHz) can be achieved, while the processing gain reaches 48 dB. In addition, this enhanced performance is maintained over long distances without periodic ambiguities, making it ideal for range imaging.