Study On Absolute Distance Measurement By Dispersive Interferometry Using Optical Frequency Comb

With the development of the aerospace and industrial technology,long distance measurement with high precision is more and more important for a country.But traditional distance measurement methods can't realize the requirement of field distance measurement,so that high-precision and long-distance absolute distance measurement methods received attention,recently.Today,lots of absolute distance measurement methods based on optical frequency comb have been proposed,the measurement range and the precision have been improved obviously.This paper will focus on dispersive interferometry absolute distance measurement theory based on optical frequency comb,and an absolute distance measurement system is set up to realize long distance measurement.The main research works of this paper are as follows:The mathematical model and signal model of optical frequency comb are established.and the properties of optical frequency comb in time domain and frequency domain are researched using these two kinds of model,which can contribute to the absolute distance measurement.The dispersive interferometry is simulated using the mathematical model of frequency comb.Analyze dispersive interferometry based on optical frequency comb in detail,such as the influence factors of non-ambiguity range and range resolution.And an absolute distance measurement system is set up to realize dispersive interferometry,this measurement system can measure the glass thickness and refractive with high precision.The measurement system is compact and stable.Based on the study of optical frequency comb and dispersive interferometry,the way to realize long distance measurement is discussed,carefully.And an algorithm is used to demodulate the frequency of the interference signal with high precision.An absolute distance measurement system is set up to realize long distance measurement,and the experiment results show an agreement within 12?m in 70 m range,corresponding to a relative precision of 1.8?10^-7.The experiments show that dispersive interferometry can realize long-distance absolute distance measurement with high precision.The way to improve the measurement precision and non-ambiguity range should be explored in the future.And the instrumentation of dispersive interferometry would be the focal point.