一种任意构型双基合成孔径雷达成像算法

A general bistatic SAR imaging algorithm

针对任意构型双基合成孔径雷达成像问题,提出了基于四阶精确传递函数的任意构型双基OMEGA-K成像算法。该算法应用四阶精确传递函数思想,首先把收发斜距历程展开至四阶泰勒级数,通过直接求解驻相点方程得到驻相点,进而获得具有较高精度的双基二维谱。通过对二维谱的处理,结合单基OMEGA-K成像算法思想,推导出任意构型的双基OMEGA-K成像算法,分析了不变区域大小。给出了算法步骤,仿真实验表明:该算法有较好的聚焦性能,可用于较为极端的双基构型。

This paper presents a bistatic OMEGA-K imaging algorithm based on Fourth-order Extend Exact Transfer Function （EETF4） 2-D spectrum for general bistatic synthetic aperture radar（SAR） data focusing. Applying EETF4, the rang histories of transmitter and receiver are approximated by fourth-order Taylor expansions in azimuth time first. Then the point of stationary phase is derived by sol- ving the polynomial equation which comes from the principle of stationary phase. Subsequently, an accurate bistatic 2-D spectrum is formulated. Based on the expression of the spectrum, a frequency mapping function is derived. Finally a bistatic OMEGA-K imaging algorithm is proposed and the invariance region is analyzed. Simulation results demonstrate the performance of the bistatic OMEGA-K algorithm.