相位细分高分辨率激光回波模拟方法研究

Study on High Resolution Laser Echo Simulation with Phase Subdivision

为了提高激光回波模拟距离分辨率,设计了基于FPGA主控芯片的回波模拟延时系统。采用粗细延时相结合的方式实现高分辨率采样,粗延时利用计数器实现大范围延时,细延时采用最小相移量相位调整次数的方法实现精细采样延时。外围电路包括串口通信模块、边缘检测模块和寄存器模块等共同组成回波模拟的延时系统。搭建实验平台并对15~6 000 m进行仿真和实验,仿真结果表明系统延时模块延时仿真误差≤100 ps,即0.015 6 m,实验结果数据表明18~6 000 m延时模块延时误差≤800 ps,即0.12 m。

In order to improve the range resolution of laser echo simulation,an echo simulation delay system based on FPGA is designed. High resolution sampling is realized by combining coarse and fine delay,large range delay is realized by counter for coarse delay,and fine sampling delay is realized by the method of minimum phase shift and phase adjustment times for fine delay. The peripheral circuit includes serial communication module,edge detection module and register module,which constitute the delay system of echo simulation. The experimental platform was built and the simulation and experiment were carried out on 15~6 000 m. The simulation results show that the delay simulation error of the system delay module is less than 100 ps,that is 0.015 6 m,and the experimental data show that the delay error of the 18~6 000 m delay module is less than 800 ps,that is 0.12 m.