一种激光雷达复合式扫描方法及试验

A composite scanning method and experiment of laser radar

传统激光雷达系统中,固态激光光源的重复频率和扫描系统的扫描带宽、精度均制约着系统成像。为提高激光雷达的成像精度,首先,在激光光源上采用经EDFA放大后的DFB高重频激光光源。其次,提出了一种PZT与振镜相结合的两级复合式激光扫描方法,利用PZT对小视场范围进行精细扫描,利用振镜对PZT的扫描视场和接收视场进行偏转完成粗扫描,在提高激光雷达扫描精度的同时拥有较大的扫描视场。最后,经试验所设计的复合式扫描激光雷达的方位角为±99 mrad,俯仰角为±49.5 mrad,角分辨率达到0.1 mrad,测距精度达到0.159 m。

In traditional laser radar system, the imaging is influenced by repetition rate of selected solid- state laser as well as scanning bandwidth and scanning precision in the laser scanning system. In order to improve the scanning bandwidth and precision, DFB high-repetition-rate semiconductor laser which was amplified by EDFA was adopted as the laser source firstly. Secondly, a two-stage composite laser scanning method had been proposed with combination of PZT and galvanometer. PZT got on meticulous scanning in small areas, then galvanometer was used to deflect and finish coarse scanning on the PZT scanning field and receiving the field. The scanning accuracy had been raised and the scanning field of laser radar had been expanded simultaneously. At last, azimuth of composite scanning laser radar is ±99 mrad, pitch angle is ±49.Smrad. Angular resolution can measure up to 0.1 mrad, and the ranging precision can reach 0.159m.