Abstract:

This paper sums up several autofocus algorithms applied to compensate space variant phase error in Spotlight SAR, and analyzes cause, property, defocus and effects on imaging of space variant phase error after phase errors coming from imaged targets with translation or rotation are analyzed. Mathematical mode of space variant phase error is given in this paper, and some conclusions are acquired on the basis of theoretical deduction, also, results of simulation support the above conclusions. Based on the traditional autofocus algorithms of space variant, a more efficient and accurate autofocus algorithm is expected while considing these conclusions.

Key words: spo t ligh t SAR, space-variant phase erro r, autofocus algo rithm