An Azimuth Nonlinear Chirp Scaling Algorithm for High Squint FMCW SAR Imaging

With the FAICW SAR working at high squint, the coupling between the range and azimuth greatly increases. A linear range walk correction(LRWC) is adopt to reduce the range-azimuth coupling and to remove the linear component of target range cell migration. After the LRWC, we can use the side-looking method for the squint SAR. Then the azimuth nonlinear chirp scaling(ANLCS) is applied to equalize the azimuth frequency modulation rate for azimuth compression in azimuth processing. In this paper, we compare and analyze range processing and the ANLCS with different accuracy in our scenes. And the simulation experiments of different processing provide a basis for choosing a better imaging algorithm for our requirement.