Study on High Resolution Overlapped Subaperture Imaging Algorithm for High Squint Airborne SAR Processing
机载合成孔径雷达大斜视高分辨率重叠子孔径成像算法研究

A high-resolution subaperture imaging algorithm incorporated with the correction of 2-D image geometric distortion and the compensation of spatially-variant phase error for high squint airborne synthetic aperture radar is presented. Each subaperture processing is based on linear range-Doppler algorithm. According to the basic theory of rotating-object imaging, a methodology is developed to realize the range and Doppler alignment of the corresponding scatterers in successive subimages by the geographical coordinate transforming and positioning, while the step transform technique based on SPECAN is employed to obtain the high-resolution image. The point-target simulations and live data processing results show the validity of the proposed approach.