基于FPGA的外差干涉信号处理方法

Heterodyne interference signal processing method based on FPGA

外差信号处理系统是外差干涉测量系统精度测量的重要组成部分。为了实现外差干涉的相位移测量,采用一种整数计数和小数计数相结合的外差信号相位测量方法,利用VERILOG语言编写整数计数以及小数计数模块程序,并进行了仿真验证,理论分析测量分辨率为(11π/375)rad。结果表明,该方案硬件实现电路简单、可移植性强,只需一个基于现场可编程门阵列的最小系统即可实现。

Heterodyne signal processing system is an important part of heterodyne interferometer system for precise measurement. In order to measure the phase displacement between two heterodyne signals, a program based on VERILOG was written combining integer counting with decimal counting to measure the phase shift of heterodyne interferenee signals. Its resolution was （11π/375 ）rad in theory. It is easy to implement because of simple hardware, just a minimal field programmable gate array system.