基于线性补偿函数的机载双基 SAR 二维频谱研究

摘要

简洁的二维频谱解析式模型是研究任意构型的机载双基 SAR 成像算法的基础。本文提出一种适用于任意构型的机载双基 SAR 二维频谱解析表达式，它是通过利用曲线拟合和驻定相位定理得到的。首先，采用泰勒级数定理将机载双基 SAR 的斜距史函数等效为双曲线和线性误差补偿函数的复合函数。接下来，利用驻定相位定理得到最终的二维频谱表达式。对于机载双基 SAR，上述二维频谱模型是精确且简洁的。最后，通过大量的仿真结果验证了上述二维频谱模型的有效性。%A concise two-dimensional frequency spectrum analytic model is the basis of general Airplane-Airplane Bistatic SAR(GAA-BiSAR)imaging algorithm. In this paper,it presents an analytic expression of frequency spectrum for general Airborne-Airborne Bistatic SAR(GAA-BiSAR) derived by utilizing the curve fitting approach and the principle of stationary phase(POSP). Firstly, the overall slant range history of GAA-BiSAR is fitted into a hyperbolic function with linear compensation function based on the Taylor formula. Then,the POSP is performed to obtain the spectrum expression. The proposed spectrum model is concise and accurate for the GAA-BiSAR. Finally,simulation results with GAA-BiSARdemonstrate the validity of the proposed spectrum model.