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 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 1mm×2 mm. Also, a phase-based signal demodulation scheme is proposed for this LiDAR, which makes the update rate of the LiDAR equal to the DAQ sampling rate, greatly increasing the dynamic performance of the LiDAR. Numerical verifications show this LiDAR can reach a micrometer resolution and megahertz update rate. The results of the proof-of-concept experiment will be given in the near future.