High Resolution SAR Imaging Algorithms And Real-time Processing Technique

Imaging as a new function of radar has been wide used in the world. It can greatly enhance the ability of information acquirement for its all time and all weather character, so it has a great value both in the civil and in the military. With the rapid development of microelectronics technology and computer technology, the research on the high resolution imaging radar hasbecome a hot field in the radar world.High resolution microwave imaging technique is an important research direction in the SAR system. This dissertation deeply investigates into the high-resolution microwave imaging technique and motion compensation technique based on airborne radar system. We achieve imaging algorithm and motion compensation algorithm suitable for the high resolution SAR system.The factors influencing the resolution of the tradition strip-map SAR imaging mode are discussed in detail. Combining the principles of high-resolution imaging, we analyze the method of increase the space resolution in detail, and we present a novel SAR operation mode—sliding spotlight mode, and we also analyze the relation ship among the strip-map, the spotlight and the sliding spotlight operational mode.The echo equation of the high resolution imaging radar is analyzed in detail firstly, and we discuss the common SAR imaging algorithm: chirp scaling algorithm, wave-number domain algorithm and polar-format algorithm, and then we discuss the influence of wave-front curvature effect on the polar-format algorithm. We analyze the application of the overlapped sub-aperture method in high resolution SAR imaging, and present the high definition imaging algorithm which is suitable to the system without adoption the dechirp on receiver technique: overlapped sub-aperture polar-format algorithm and overlapped sub-aperture algorithm (OSA).The phase error caused by the non-ideal movement of the aircraft is analyzed. We discuss the motion compensation characteristic of IMU, GPS and combination IMU and GPS and recommend the method of motion compensation using GPS and IMU. We analyze the auto-focus algorithm in...