High squint mode SAR imaging using modified RD algorithm

Based on the analysis of range-azimuth coupling in two dimensional frequency domain, a modified RD algorithm is proposed to account for the problem of SAR imaging with high squint angle. The measures of decoupling consist of second range compression (SRC), third order coupling compensation and range cell migration correction (RCMC). In addition, the type of RCMC is modified to eliminate target´s movement in range direction which will cause the blur of distance. Simulation results verify the proposed algorithm and perfectly focused image is obtained with a squint angle as large as 80 degree.