The Research Of The SAR Image Float-Point Compression

SAR (Synthetic Aperture Radar) is one of the most important orientations of modern radar technology development. It is a type of microwave-to-ground observing equipment, working in various weather conditions and all the time. The data compression is an essential key technology of SAR. With the increasing improvement of performance index of SAR such as resolution and mapping bandwidth, its output data rate will be greatly increased. In the end, its requirements for data compression algorithm will be increasingly higher. According to the requirements of a certain institution and combining with the characteristic of floating point module image data after the authentic on-board SAR, this article carries out the research on the compressing method of self-adapting regional coding based on DCT, via nonlinear preprocessing, and on the Huffman coding also. The experiments show that these technologies can achieve an ideal effect.The article is involved into the analysis of the coming into being, application and development of SAR, and the classification of the SAR data also.In Chapter 2, the basic theory and approaches of data compression, the methods, the standards and the evaluation of image compression, and along with the necessity of the SAR's image-data compression, are clearly described.Chapter 3 analyzes the self-adapting regional coding method based on DCT's functions, which applied on the data compression based on 32-bit floating point module image of the SAR.Chapter 4 sheds light on the developing approaches of nonlinear pre-treatment, and achieves the fixed compression ratio based on the SAR's floating point module image data.In the last chapter, the main task is placed on the SAR's floating point module image data compression based on Huffman coding.The conclusion gives its general idea for the article, and develops its imagination and set up the new direction for further research.