圆迹SAR极坐标格式算法研究

 该文提出一种新的用于圆迹合成孔径雷达(Circular Synthetic Aperture Radar, CSAR)成像的极坐标格式算法。在CSAR模式下，点目标的波数域3维频谱为3维曲面。根据这一特点，算法采用逐高度平面成像的方法最终获得3维图像，即通过参考函数相乘，将频谱投影到2维平面，既避免了高度向的插值，又保证了算法的精确性。并且该算法通过两步相位补偿操作校正了越距离单元徙动的高次项，扩大了有效成像范围，避免了场景边缘目标的散焦。最后，点目标仿真验证了该算法的有效性。

Polar Format Algorithm for Circular Synthetic Aperture Radar

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.