Research Of Motion Compensation Of SAR Imaging On A Style UAV

Synthetic aperture radar(SAR) enhances radar's information acquisition capability and information awareness ability by obtaining high resolution imageries. Now, SAR has been widely used in airborne radar system as a new function of modern radar. Especially for litter airborne SAR platform flying at middle and low height, Its flight path and motion attitudes are hardly controlled in the influence of airflow during the period of recording data. It has important application value and academic value doing for research on motion error analysis and motion compensation.Studying the technology of SAR is usually based on SAR imaging. They are necessary to SAR imaging comprehending the theory of SAR and applying SAR imaging algorithm. The theory of SAR is introduced from physical concept and SAR imaging processing using simulated data. Then common SAR imaging algorithms are discussed.Motion compensation is one of the key steps in the signal processing of a SAR system. Motion compensation is based on measurment instrument or the SAR real data. The latter is particularly studied in this dissertation. It is helpful to fulfill motion compensation analyzing motion error through raw data. Firstly, we set up a motion error model and propose a method to analyze the motion error based on the returns of strong scatterers. Then different raw data of the SAR which we research are analyzed, and the rules of motion error are obtained. Based on the analysis, the appropriate compensation policies are proposed. According to the results of motion error analysis, the motion compensation approaches basing on the estimation of Doppler instantaneous chirp rate and phase gradient autofocus (PGA) are discussed in detail.