Polar Format Algorithm for Circular Synthetic Aperture Radar
圆迹SAR极坐标格式算法研究

In this paper, a novel Polar Format Algorithm (PFA) is presented for Circular Synthetic Aperture Radar (CSAR) imaging. Based on the signal model analysis, it is finded that the shape of the spectrum in the wavenumber domain of a point target in CSAR is a three-dimensional curved surface. To avoid the interpolation along the third dimension and also ensure accuracy, this algorithm obtains two-dimensional images at equally spaced heights to form the final three-dimensional image, and this is done by multiplying reference function of height to project the spectrum to two-dimensional planes. By two steps of phase compensation, this algorithm also corrects the high terms of the Range Cell Migration (RCM) to enable full image quality over much larger scenes without image defocus. Finally, simulation results validate the feasibility of the proposed approach.