Research Of Doppler Parameter Estimation Algorithms For Spaceborne SAR

Synthetic Aperture Radar (SAR) is an active pattern on the earth observation system after the War II, it can be installed in aircraft, satellites and other flying platform. It can be used to implement observation at all weather condition, at any time, it also has the ability to penetrate the surface. With the development of SAR image technology, the image quality continuously improved. It has becoming the irreplaceable high-tech detection, reconnoitered measure, and also has a great value and broad application prospect in the military, economic, scientific research, and other aspect.Firstly, this article reviewed the history of development for synthetic aperture radar, and the research of Doppler parameter estimation algorithm for spaceborne SAR.Secondly, the paper introduced the principles about SAR, including LFM, Matched Filtering and Pulse Compression and so on. Among it, we mainly analyzed the causes of range cell migration and the Statistical Properties of SAR Echo-wave Signal in range-Doppler.Then, the theories of the traditional Doppler parameter estimation algorithms, including the maximum method, energy method and correlative function for Doppler centroid frequency, polynomial method, map_drift(MD) and shift_and correlation(SAC) for the slope of Doppler frequency estimation, for spaceborne SAR are are expounded exhaustively. Contrary to the disadvantages of these methods, the joint estimation of Doppler parameters for spaceborne SAR by contrast minimization is studied.Finally, Contrary to the above theories, specific method is proposed and the experimental results based on real Radarsat-1 data are provided to demonstrate the effectiveness of the proposed method.