机动车激光测速仪校准技术的研究

Study on Lidar Calibration Technique for Vehicle Speed-Measuring Device

依据移动式（单光束）和固定式（双光束）红外机动车激光测速仪共同的测量原理,提出了一种基于时间延迟的校准方法。采用虚拟仪器技术的机动车激光测速仪校准系统,将激光测速仪发射的905 nm测量脉冲激光光束进行特定时间量的延迟,以模拟其在空气中对应的传播距离,实现固定时间间隔激光脉冲串测量的距离变化量的精确模拟,完成机动车激光测速仪在20～250 km/h时速范围内任意速度值的实验室准确校准,其时间延迟分辨率为5 ps,对应位移分辨率为0.75 mm,模拟速度不确定度优于0.5%（k=2）。

A novel lidar calibration method is presented, which is based on time delays applied to the measurement of infrared laser vehicle speed measuring devices, either portable （one-beam） or fixed （two-beam）, according to their common opmtion principle. By simulating the transmitted distances of laser pulses of 905 nm in the air with certain amount of time delays required, the calibration system is developed with the help of virtual instrument technology, which leads to a successful calibration of lidar devices at any speed in the range from 20 km/h to 250 km/h with a time delay resolution of 5ps, displacement resolution of 0.75 mm and an expanded uncertainty of 0.5% （k = 2）for speed simulated.