面内位移测量的激光多普勒信号研究

在利用激光多普勒效应进行远距离处固体面内位移测量时，散射光的多普勒信号强度、信噪比及信号质量是位移测量的极重要参量，它们直接影响位移测量的距离和精度。为此研究了激光多普勒差动方法、锁相放大、数字滤波等技术，设计出能获得最好结果的差动光路以及高灵敏度、高Q值的锁相放大器和能重构丢失信号的同态滤波系统等，实现了50m处固体面内位移测量，其最大相对误差可以达到1.5％。

Study on Signals of In-Plane Displacement Measurement Utilizing Laser Doppler Effect

When utilizing laser Doppler effect to measure in plane displacement of an object at long distance, the intensity of Doppler signals of scattering light, SNR and quality of signals are very important parameters, and they affect the distance and accuracy of displacement measurement directly. The Doppler differential method, lock in amplifier and homomorphic filter are studied. A differential optical measuring system with the best effect, a lock in amplifier with high sensibility and high Q and a homomorphic system that can re construct the lost signals are designed. So the transverse displacement measurement of object at distance of 50m is accomplished with the maximal relative error of 1.5%.