Photonic Doppler Velocimetry System With Adjustable Reference Light Frequency

After years of development and research,the measurement objects of Photonic Doppler Velocimetry system are more and more abundant,and the accuracy of speed measurement is also improving.With the research and development of detonation detection,new materials and energetic materials,higher requirements are put forward for the velocity measurement range of PDV system.In order to improve the velocity measurement limit of PDV system,two PDV systems based on adjustable frequency of reference light are proposed in this paper.The details are as follows:1.Proposed and built a PDV system based on MZ-modulated reference light;Deduced the MZ modulation and velocity measurement principle in detail;Observed the difference frequency signal between the reference light and the signal light after MZ modulation,and carried out low-speed measurement experiments;Used Matlab to simulate the speed measurement experiment of the high-speed moving objects,and the feasibility of improving the upper limit of the speed measurement of the system was proved.2.A miniaturized laser with adjustable frequency was fabricated and its stability was tested;A dual-light source PDV system was built,and a low-speed measurement experiment was performed;Then the experiment of measuring the speed of high speed moving objects with dual light source PDV system was simulated by Matlab..3.The experimental data were processed by moving average filter and fringe method,the velocity of moving objects such as shaker was calculated,and the influence of laser stability on the velocity measurement accuracy in the dual-light source PDV system was analyzed.