基于微增量二维谱的OMEGA-K双基SAR成像算法

Novel OMEGA-K algorithm for bistatic SAR imaging based on micro-increment bistatic 2-dimensional spectrum

结合OMEGA-K算法和微增量双基二维谱算法实现双基合成孔径雷达成像。使用微增量算法获取斜距历程低阶泰勒展开驻相点,通过求解此驻相点与斜距历程高阶泰勒展开驻相点之间的微增量,来获取高阶展开驻相点的近似解,并以此为基础得到二维谱。应用角度不变假设,通过对此二维谱的数学分析和适当处理,使之可以应用于OMEGA-K算法中,实现双基聚焦成像,并对不变区域大小进行分析。仿真实验处理结果验证了所提算法的有效性和正确性。

The bistatic synthetic aperture radar （SAR） imaging is implemented by combining OMEGA-K with micro-increment bistatic spectrum algorithm. The micro-increment algorithm can estimate the point of sta tionary phase when the range history is a Taylor expansion with low order. By computing the micro-increment between the obtained point of stationary phase and its counterpart when the range history is a Taylor expansion with high order, the high-order point of stationary, phase can be estimated approximately. Using the obtained high-order point of stationary phase, the two dimensional spectrum can be obtained. By some mathematical transformations, the obtained spectrum can be applied to the OMEGA-K imaging algorithm to focus bistatic SAR data. The invariance region is also analyzed. The simulation results are provided to demonstrate the effec tiveness of the proposed algorithm.