A Study On SAR Imaging Techniques And SAR Image Visual Enhancement

Synthetic Aperture Radar (SAR) is a kind of modern high resolution microwave imagingradar, which works without being affected by time and weather. SAP, has got rapid growingsince it was invented in the 1950's. It gets high resolution in azimuth by synthetic aperturetheory, and high resolution in direction using pulse compression technique. SAR can gethigh resolution radar images like optical photos under bad visibility weather condition. Thispaper mainly studies the SAR imaging algorithms and SAR image visual enhancement.Chapter 1 interprets the essentials of SAR in a variety of aspects. The history, presentsituation, and main trend of SAR are reviewed. The contents of this paper are outlined.Chapter 2 expounds the basic theory of SAP, from aspects of high range resolution, highazimuth resolution and range-azimuth coupling.Chapter 3 researches several kinds of SAP, imaging algorithms, including Range-DopplerAlgorithm, Modified Range-Doppler Algorithm with Second Range Compression, ChirpScaling Algorithm, Wave-number Domain Algorithm and Monochromatic Wave-numberDomain Algorithm. The principle and performance of each algorithm are expounded indetail; the implement steps presented, formulas deduced, and computer simulation are made.Finally real SAR data are processed using these algorithms.Chapter 4 firstly introduces a grayscale image enhancement algorithm under dynamicrange constraints. Then two SAR image visual enhancement algorithms are presented. Oneis based on the sub-image fusion, and the other is through dynamic range compression ingradient domain.Chapter 5 summarizes the whole work of this paper and points out the problems to besolved in the future.