外差式激光干涉信号的采集与解调方法综述

Review of acquisition and demodulation method of heterodyne interferometer signal

外差式激光干涉仪被广泛应用于激光干涉法振动绝对校准。基于外差式激光干涉仪的振动测量原理及其干涉信号的特点,重点阐述了现有外差式激光干涉信号采集方法的采集原理,采样频率与采样精度等的特点;分析总结了现有外差式激光干涉信号解调方法的解调原理,解调精度与实时性。针对现有干涉信号采集方法在采样频率与精度,解调方法在解调精度、实时性及降噪处理等方面存在的问题,提出改进建议,以提高外差式激光干涉仪振动测量的精度与实时性。

Heterodyne interferometer has been widely used in primary vibration calibration by laser interferometry. In this paper, based on vibration measurement principles of the heterodyne interferometer and its interferometer signal characteristics, elaborates sampling principles of current acquisition methods for heterodyne interferometer signal, and their characteristics of sampling rate and sampling precision, and analyzes principles of the heterodyne interferometer demodulation methods, demodulation precision and timeliness to improve vibration measurement precision and timeli- ness of the heterodyne interferometer. Some improvements suggestions have been proposed for existing problems of those acquisition methods in sampling rate and precision and demodulation methods in demodulation precision, timeli- ness and noise reduction.