High-precision ranging and speed measurement technology based on coherent dual-frequency laser

A coherent dual-frequency lidar architecture for long-distance high-precision ranging and velocity measurement is proposed, using the method of optical heterodyne detection, which can avoid complex optical coherence configurations. The system uses a dual-frequency laser with a beat frequency of 200MHz as the dual-frequency light source, and performs measurement through the principles of phase ranging and Doppler velocimetry. The experimental verification shows that the operating distance of the system reaches 3200m, the distance resolution is less than 0.5m, and the speed measurement accuracy range is ±0.25m/s. The results show that the system can realize long-distance high-precision single-point ranging and speed measurement.