Study Of Target Detection Based On Laser Reflective Tomography Imaging

Laser reflective tomography imaging(LRTI)is a laser imaging approach to get high resolution image in remote distance.Its superiority is demonstrated in three aspects.First,long detection range independent of coherence of light source compared with traditional optical imaging.Second,imaging resolution of nanosecond-class pulse width laser could reach towards centimeter-class compared with traditional microwave radar imaging;Third,simple and practicable system compared to laser synthetic aperture imaging,which make it a new imaging means giving comprehensive consideration to detection range,resolution and application difficulty.Particularly,based on the above advantage,LRTI is suitable to detection of space target in satellite-borne environment.In this paper,basic principle of computed tomography is studied and similarities and differences with laser reflective tomography imaging are analyzed.major reconstruction and data processing algorithms are studied.A model of laser reflective tomography imaging target detection feedback wave,hereby multi-frame iterative blind deconvolution method is proposed to solve the fuzzy problem in image reconstruction.A model of space debris barycenter,hereby barycenter location method and process based on are proposed.Programs are compiled to simulate all models and algorithms.Experiment platform of laser reflective tomography imaging target detection is built.Various of models are made as imaging targets,with which target feedback wave deconvolution experiments,target reflectance distribution experiments and debris target barycenter location experiments are conducted.Different target reconstructed outline images are acquired,confirming the practicability of experiment platform and proposed multi-frame iterative blind deconvolution method and other algorithms.Centimeter-class position accuracy of barycenter is implemented on the detection distance of 50 m.The major innovations of this paper are listed as follow:1.According to modulation characteristic of target reflectance and structure to laser pulse,combined with principle of laser reflective tomography imaging,target detection feedback wave convolution model by transmission pulse and target reflectance distribution function is proposed,which lays the foundation of follow algorithm research.2.Taking advantages of similarity of convolution core in laser reflective tomography imaging,multi-frame iterative blind deconvolution method is proposed,which has been confirmed in actual lidar experiments enable to compress pulse and improve resolution of reconstruction images.3.Barycenter location method of space debris based on laser reflective tomography imaging is proposed,and experiment results demonstrate that it could precisely locate debris barycenter,as well as limited projection angle range could obtain a high degree of precision.