Research On Interference Detection Technology Based On Optical Correlation In Space

Spatial targets detection and identification are the most important research directions in many countries at present.They are widely used in the fields of aircraft identification,missile early warning and detection in the vicinity of the atmosphere.Traditional space target interference detection adopts the laser detection method,it emits the laser beam to the target,receives the echo signal and detects targets according to the phase information of the coherent signal.Quantum depression phenomenon is due to the object inserted into the interference field causing by interferogram distortion.The phenomenon is due to the quantum properties of the optical system itself.The insertion of objects makes the transmission of the interference light wave with uncertainty and asymmetry,resulting in detectable interference pattern distortion.In this paper,the interference detection and optical joint transform correlator are taken as the research background.The principle of interference of the object to the grating interference field is deduced in detail,and the influence of object size and position on the interference field is analyzed.The essence of its influence lies in that the object insertion breaks the symmetrical distribution of the original interference field and modulates the partial path in the interference field according to its own complex amplitude distribution so that the local interference field has spatial asymmetry and causes interference Pattern distortion.In this paper,the original interference field and the distorted interference field are identified by using the optical correlation method,and the preprocessing algorithm of the interference image is researched deeply for the defects in the optical correlation recognition.From the edge detection,threshold segmentation and image removal Noise and other aspects of the simulation and improvement,proposed a multi-scale morphology,based on the local entropy fast threshold segmentation and adaptive wavelet denoising improved algorithm.The effectiveness of the improved algorithm is verified by Matlab simulation.The improved algorithm has obvious improvement on the optical correlation recognition results.At the same time,this dissertation builds an experimental platform,which mainly includes two parts of interferogram acquisition and optical correlation,including DMD control,image acquisition,power spectrum acquisition and correlation recognition.By collecting the interference field patterns before and after distortion,the relevant images are identified.The correlation of distortion interference field is low,it can’t see the obvious correlation peak,which played an early warning object in the interference field.