极坐标格式算法(PFA)在逆合成孔径雷达(ISAR)成像算法中主要运用插值算法来解决目标散射点越距离徙动问题,其插值方法的选择决定了成像效率和运算速度。提出了一种沿雷达视线插值的方法,建立了ISAR大转角目标几何模型,对其进行理论推导得到方位向的精确插值形式,并对因非均匀采样造成的形变进行方位重采样。仿真实验表明,相较于传统插值算法,该算法有着运算速度更快、聚焦性更好的优点。

The Polar Format Algorithm (PFA) mainly uses interpolation algorithm in the Inverse Synthetic Aperture Radar (ISAR)imaging algorithm to solve the problem of cross-range migration of scattering points.The selection of the interpolation method determines its imaging efficiency and computing speed.In this paper, an interpolation method along the line of sight of radar is proposed.The geometric model of ISAR target with large rotation angle is established, the precise interpolation form of azimuth direction is obtained by theoretical derivation, and azimuth resampling is carried out for the deformation caused by non-uniform sampling.Simulation results show that compared with the traditional interpolation algorithm, it has the advantages of faster operation speed and better focusing performance.