红外, 2010, 31 (6): 1, 网络出版: 2011-02-23
脉冲式高精度激光测距技术研究
Study of High-precision Pulsed Laser Range Finding Techniques
摘要
本文对脉冲式激光测距仪的误差来源进行了分析,着重讨论了影响测距仪随机误差的几个因素。通过分析可以 看到,提高时间间隔测量电路的分辨率,采用高速阈值鉴别芯片以及缩短信号上升沿是提高测距精度的有效方法。其中,信号上升沿的 缩短可以通过采用窄脉冲激光器以及适当的接收电路带宽来实现。通过仿真计算得到,保持5ns上升时间不被扩展的最小带宽约为90MHz。 采用这个思路设计了一种高精度激光测距系统。经测试,该系统对500m内不同距离目标的单次测距精度(3σ)在0.077m ? 0.115m之 间,对距离在500m到3km的目标则优于0.1‰D+0.05m (D为距离)。同之前采用不同激光器和带宽的设计相比,该系统的单次测距精度有了明显的改善。
Abstract
The error sources of pulsed laser range finders are analyzed and the factors which have influences on the random error of a pulsed laser range finder are primarily considered. It is found that improving the time resolution of a TDC, using a high speed threshold discriminator chip and reducing the rising edge of a pulsed signal are the effective methods for improving ranging precision. Among them, the reduction of a pulsed signal can be realized by using a narrow-pulse laser and a receiving circuit with a properly designed bandwidth. Simulation shows that the minimum bandwidth required to keep a 5ns rising edge from extending is 90MHz. Then, a high-precision laser range finder is designed and tested. The test result shows that the system has a single-shot precision (3σ) from 0.077m to 0.117m for the targets at different distances within 500m and has a precision better than 0.1‰D+0.05m (D stands for the distance) for the targets at different distances from 500m to 3km. Compared with the formerly designed systems using different lasers and different bandwidths, this system has obviously improved its single-shot precision.
陈弈, 郭颖, 杨俊, 黄庚华, 舒嵘. 脉冲式高精度激光测距技术研究[J]. 红外, 2010, 31(6): 1. CHEN Yi, GUO Ying, YANG Jun, HUANG Geng-hua, SHU Rong. Study of High-precision Pulsed Laser Range Finding Techniques[J]. INFRARED, 2010, 31(6): 1.