Mechanism And Experimental Study For Micro-doppler Measurement Based On Photon Heterodyne

For the need of high-precision detection in the field of long-range laser micro-Doppler detection,A micro-Doppler detection system based on photon heterodyne,Combine photon heterodyne and micro-Doppler detection,is proposed in dissertation.It will fill the grap of micro-Doppler detection technology for weak optical signal.Firstly,We have analyzed and summarized the research status of Photon heterodyne and micro-Doppler detection at home and aborad,summarized the working principle,system structure,response model,transmission mechanism and spectrum extraction method of Photon heterodyne detection system.We studied and analyzed the detection of micro-Doppler information.The modeling scheme and basic model of micro-Doppler based on Photon heterodyne are given.By analyzing the signal model of the precessing target,we find the signal can be decomposed into a superposition of micro-Doppler signals generated by three basic motions of uniform speed,vibration and uniform speed.The Doppler information extraction method of photon heterodyne is studied.The method of collecting Doppler information form Photon heterodyne and thescheme design are carried out.We simplify the theoretical model of Photon heterodyne,through theoretical analysis of the action process of photon-level signals and local oscillators.The method and extraction scheme of collecting micro-Doppler information form Photon heterodyne are carried out,through the corresponding simulation and analysis.We carried out the experimental study of collecting micro-Doppler information form Photon heterodyne.The simplified model verification experimental system for photon heterodyne detection proposed in this dissertation is designed and built,which verifies that the detection efficiency of the system is the highest when the ratio of the local oscillator light intensity relative to signal light intensity is 1.Besides,the spectrum broadebing is inversely proportional to the signal intensity,and the relative standard deviation of the signal is proportional to the reciprocal of the tital number of detections.The experimental study of collecting micro-Doppler information form Photon heterodyne detection system is carried out,and the device parameters of the system were selected.The uniform shift target is detected by the photon heterodyne micro-Doppler detection system,and the corresponding time-frequency map is obtained and the target acceleration is estimated to be 6.34 rad/s~2.