应用于激光雷达的高精度时间间隔测量方法

摘要

针对当前脉冲激光测距雷达中时间间隔测量精度低的问题,文中提出了一种高精度时间间隔测量方法.该方法采用双环形振荡器作为时间内插器,利用其输出的可控频率时钟信号对时间间隔做内插和逼近,实现时间间隔的粗测量和精测量,然后结合改进的时域互相关算法对测量结果做估计.实验结果表明,当环形振荡器的时钟为50 MHz时,时间测误差小于20 ps.%Aiming at the problem of low precision of time interval measurement in pulse laser ranging radar,a high precision time interval measurement method was proposed in this paper. In this method, a double ring oscillator was used as the time inter-polation device, which used the controllable frequency clock signal of the output to do interpolation and approximation of the time interval, and to realize the coarse and precise measurement of time interval. Then, the measured results were estimated by the improved time domain cross-correlation algorithm. The experimental results show that the error of time measurement is less than 20 ps when the ring oscillator clock is 50 MHz.