Chip-based microwave-photonic LiDAR for high-speed ranging and velocimetry

As a fast and accurate active ranging technique, LiDAR (Light Detection and Ranging) plays an increasingly important role in the future intelligent society. Driven by the fast-booming miniaturized robotics industries, the small-size, lightweight, and low-power LiDAR with a high update rate shows huge application perspectives and is highly desired. In this paper, a novel microwave-photonic frequency-modulated continuous wave (FMCW) LiDAR based on a silicon-photonic chip is proposed, which can realize simultaneous distance and speed sensing. The FMCW generation, LiDAR signals passive processing and photoelectric detection are integrated into a single silicon photonic chip with a footprint of about 1mmx2 mm. Also, a phase-based signal demodulation scheme is proposed for this LiDAR, which makes the update rate of the on-chip LiDAR equal to the DAQ sampling rate, significantly increasing the dynamic performance of the LiDAR. Numerical verifications show that this LiDAR can reach 10 MHz update rate, as well as 1 mu m-level range accuracy, and 5 mm/s-level speed accuracy. The results of the proof-of-concept experiment will be given in the near future.