Level Flight Is Side-looking Bistatic Sar Parameter Estimation And Motion Compensation

Airborne Bistatic Synthetic Aperture Radar (Bi-SAR) system installed transmitter and receiver on separate platforms individually. In recent years, Bi-SAR has become a hotspot in international research field due to its peculiar advantages such as long detecting distance, high security, high anti-jamming ability and abundance information acquiring ability, etc.As a newly developed radar system, Bi-SAR confront several new problems, such as much more complicated geometrical and signal models, synchronization problem and much more complicated motion compensation, in theory and practice.These problems will increase the difficulty of signal processing. The work of the thesis shown below:1. Build the geometrical and signal models under arbitrary flying-mode. Based on these studies, the doppler characteristics are analyzed.2. The echo's doppler characterize under the parallel flying mode are analyzed, and its doppler parameters and range migration's equation are derived by the two-order approximation.3. The feasibility of RD algorithm in Bi-SAR's CT (Cross Track) broadside side-looking mode has been validated by simulation and experiment results,meanwhile, the limit of RD algorithm has been analyzed. Then its improved algorithms, SRC algorithm and SIM algorithm, have been given.4. The algorithms of Bi-SAR doppler parameters estimation are studied. Sevaral algorithms are given, meanwhile, their performance and characters are compared. These algorithms'feasibility have been validated by simulation.5. The origins of the phase errors and its influence to the imaging quality are analyzed. Motion compensation based on GPS/INS/IMU control system and PGA (Phase Gradient Auto-focus) algorithm have been studyed. The feasibility of PGA has been validated by simulation.