Design And Implementation Of Underwater Laser Imaging System Based On Ghost Imaging

Correlation imaging,also known as "ghost imaging",is an emerging imaging technology in recent years.Because of its good anti-interference properties,it has become one of the hot spots in the field of optics and quantum research.Compared with the traditional underwater sonar imaging technology and underwater laser imaging technology,ghost imaging uses a barrel-type detector for beam collection,which greatly improves the detection distance.Therefore,research on underwater laser imaging technology based on ghost imaging is of great significance for future ocean exploration and development.This thesis designs an underwater laser imaging system based on ghost imaging for practical engineering applications based on ghost imaging.The main work completed in this thesis is as follows:Starting from the basic principles and models of ghost imaging,we focus on the factors that affect the image quality and commonly used speckle field matrix in ghost imaging.Secondly,the advantages of using ghost imaging to detect the underwater environment are analyzed based on the absorption and scattering of light by water.Finally,based on the computational ghost imaging model,the whole scheme of the underwater laser imaging system is designed.An underwater laser imaging hardware platform that can work closely with the optical system is designed according to the overall design scheme of the underwater laser imaging system,including a signal acquisition board with external trigger synchronous timing control function and laser echo signal acquisition function and a signal processing board integrating high-performance FPGA and multi-core DSP.At the same time,a data transmission interactive network including SRIO,JESD204 B,etc.was built inside the underwater laser imaging hardware platform,and between the underwater laser imaging hardware platform and the host computer.Based on the underwater laser imaging hardware platform,according to the characteristics of FPGA and DSP,the specific FPGA and DSP implementation schemes are designed through reasonable function division.According to the implementation plan,the hardware acceleration of the computational ghost imaging algorithm and the acquisition function of the target echo signal are implemented in the FPGA,and the bilinear image interpolation algorithm is implemented in the DSP.At the same time,the high-speed serial data transmission interactive network,serial port,network port and other resources within the underwater laser imaging hardware platform are used to achieve reliable command interaction and interaction between the underwater laser imaging hardware platform,the underwater laser imaging hardware platform and the host computer The data transmission function guarantees the realization of various workflows of the underwater laser imaging system.Finally,through the underwater imaging experiment,the correctness of the entire design was verified.