为了提高脉冲激光测距系统的测距精度,文中提出了一种应用FPGA技术对脉冲激光测距系统的改进方法.在研究传统的激光测距技术的基础上,采用FPGA作为系统主控芯片,通过DCM倍频技术对系统时钟频率进行管理,控制激光发射器的脉冲发射频率,对激光探测器接收到的回波信号进行峰值检测处理.分析了时间间隔测量误差、激光脉冲宽度与A/D转换速率等影响测距精度的因素.实验结果表明改进后的激光测距系统,在FPGA全局时钟频率为300MHz,测量距离为100m时,测距精度能够达到0.8m.
This paper presents a method to improve the pulse laser ranging system in order to get a higher accuracy. On the basis of the traditional laser ranging technology, the FPGA is used as the master chip and the frequency doubbing teehnology of DCM is adopted to manage the clock frequency in order to control the palse frequeny of the laser transmitter. The echo signals obtained by the laser detector are processed with the approach of peak detection. Furthermore, this paper analyzes the factors which influence are detection performance, such as the measurement error of time interval, pulse width of laser, A/D conversion rate and so on. The experimental results show that the ranging accuracy of the improved laser ranging system can reach 0. 8 m when the global clock frequency of FPGA is 300 MHz and the measured distance is 100 m.