Sar Real-time Processor Pretreatment And Transpose Storage Technology Research And Implementation

The SAR can get radar image with high resolution at state of plane-loaded. The technology of SAR takes application vastly both in military and civil fields. The azimuth preprocessor and the Corner Turn Memory (CTM) are the important parts of the real time imaging processor of SAR(Synthetic Aperture Radar). Due to the complexity of the image algorithm and the large amount and high-speed of the radar data transaction, it is a real challenge for real-time realization of azimuth preprocess and CTM. So far, it is very important to achieve the azimuth preprocess and the CTM efficiently and real-timed with refined structure and software- hardware optimization.This paper focuses on real-time signal process in the plane-loaded SAR system. Firstly the image theory of SAR is introduced. Secondly the azimuth preprocess of image process is analyzed at the background of the project of the real-time imaging processor for plane-loaded SAR of IECAS(The Institute of Electronics of Chinese Academy of Sciences). Herein the ADSP21160 is employed as the core processor to carry out the azimuth preprocess. The structure planning and software flow optimized, the hardware resource exploited economically, the real-time preprocess of azimuth isrealized.Based on the theory of the SAR real-time image CTM, this paper discusses twotypes of structures of CTM: the three-frame structure and the two-frame structure. The merits and shortcomings of them are compared respectively. The two-frame structure is emphasized and its representative usage is introduced with the concrete circuit diagram. To meet the practical requirement, this paper develops a new type of high-speed and large-amount real-timed memory, taking the large scale DDR SDRAM as main memory, the latest million-gate FPGA of Altera Inc. as controller component, and the memory control based on IP core(Intellectual Property core).