VideoSAR Imaging Processing Algorithm And Its FPGA Implementation

Synthetic Aperture Radar(SAR)is a high-resolution imaging radar.It works in microwave band,it has strong penetration and is not affected by clouds,fogs,rain and so on.Therefore,it can acquire the image of the detection area all day and all night.Traditional spotlight SAR imaging mode can only get static target image because of the low frame update rate,and can not obtain the moving direction,speed and other related information of the moving target in the scene,or even can not distinguish the static target from the dynamic target in the scene through the still image.Video SAR is an extension of the classical spotlight SAR imaging mode.By increasing the frame update rate,it can provide continuous video observation of the imaging area and obtain the information of dynamic targets in the scene.In this thesis,the characteristics of moving target in Video SAR echo and frame image are analyzed in detail.The theoretical basis of Video SAR imaging processing and moving target detection is provided.Based on the modified Polar Format Algorithms(PFA)algorithm,an image processing method for frame image generation of Video SAR is proposed.In order to realize real-time image processing,a Video SAR imaging processing system based on FPGA is designed,the performance of the algorithm and FPGA implementation is verified by simulation and real data processing.There are six chapters in this thesis.The main contents of each chapter are as follows:Chapter 1 is the introduction,which introduces the research background of Video SAR system,the development status at home and abroad,and the significance of the application scenario imaging technology.Finally,the main work of this thesis is introduced.Chapter 2 is Video SAR imaging analysis based on PFA algorithm.The characteristics of moving target are analyzed from SAR echo data and PFA algorithm processing.The main parameters of Video SAR imaging are introduced.Video SAR imaging algorithm based on PFA processing for sub-aperture segmentation of full-aperture imaging is proposed through index analysis.Chapter 3 shows the hardware module of FPGA.The hardware composition and timing control of the two most important data storage modules DDR3 SDRAM and Flash in this design system are introduced.Finally,the A/D conversion module is introduced,which provides a theoretical basis for the real-time performance of the system.The feasibility of the storage control module is verified by the actual test of the development board.Chapter 4 introduces the Video SAR imaging algorithm based on FPGA.The system design of the whole Video SAR imaging algorithm based on FPGA is proposed.The collective control timing and module architecture are explained.The feasibility of the whole system is verified.Chapter 5 is the Verification and data analysis of Video SAR imaging system.The hardware implementation platforms are introduced.Through error analysis of the results processed by MATLAB,it is verified that the Video SAR system based on FPGA processing has super-high accuracy.The whole system is verified again from two aspects of processing efficiency and resource occupancy.Finally,summarizes and prospects the research content of this thesis,explains the advantages of this system design,and points out the areas that can be improved,and points out the next research direction.