Study Of Laser Interferometer For Surface Vibration Signal Measuring

Traditional perimeter security protection management system(HLC-DS,fiber optic vibration alarm system,electric cable vibration alarm system,cctv,etc)can not fulfill the requirements of safety protection management in our country because of its drawbacks,such as poor performance,high rate of false positives,etc.Based on the actual needs,in order to develop monitoring device with high sensitivity for building perimeter security protection system,there are pressing needs in the innovation of perimeter protection technology on the basis of enhancing the quality of security protection work.In this paper,we built a perimeter security protection system with high sensitivity for monitoring the vibration signal of surface.In this direction,theoretical derivation and experimental research under laboratory conditions are also carried out on the working principle of measuring surface vibration signal using polarized laser interferometer.Firstly,the study status of laser interferometer vibration technology is raised on the basis of introducing the development state for perimeter security protection technology in this paper.The principle of interferometric surveying was analyzed by giving an example of traditional Michelson interferometer,and the working principle of measuring vibration signal by polarization interferometer was established.The nonlinearity error caused by light path of interferometer and optical element used in the process of building is also researched.Secondly,based on the receiving mode of Interference signal used in the process of building polarized laser interferometer and nonlinearity error existed in the optical platform,this paper studies nonlinearity error calibration algorithm and signal subdivision algorithm.Then it further discusses the principle of the nonlinearity error calibration arithmetic and signal subdivision algorithm,and the method of building a signal demodulation platform through software on the PC.Thirdly,we also use software written by LabVIEW to control the polarization interferometer on the software platform,and process the collective signal on the PC platform.The Real-time control of NI9215 acquisition card is achieved through software program written by LabVIEW on the PC platform.Then the real-time displaying and processing for received interferometer signal can be achieved on the PC.In the end,we test the constructed perimeter security protection system under laboratory conditions,monitor the surface vibration signal in real-time manner,build the polarized laser interferometer,and debug the software program.According to the experimental results,surface vibration signals within a certain frequency range can be monitored by perimeter security protection system taking polarized laser interferometer as main body.This paper investigates the light path structure of polarized laser interferometer,the nonlinearity error calibration algorithm,the vibration signals subdivision algorithm,and designs the real-time monitoring platform based on the software program.The construction of the perimeter security protection system on the basis of measuring the surface vibration signal by polarization interference is preliminarily completed under laboratory conditions.