一种基于相位对消的转角估计新方法

逆合成孔径雷达成像中，为校正散射点越多普勒单元走动和方位向定标，需要对目标转角进行估计。在详细分析雷达目标回波相位特性的基础上，提出一种基于相位对消的转角估计方法。该算法通过对消回波的相位一次项后，对回波相位二次项系数进行估计，从而根据二次项系数与转角的关系获得转角估计值。同时，考虑到回波能量在成像平面的分布特点，采用加权最小二乘法对估计结果进行拟合。与现有方法相比较，新方法在稳健性和实时性上有较大改进。仿真数据和暗室数据的成像结果证明了该方法的有效性。

Novel method for estimating rotation angle based on phase cancellation

In the inverse synthetic aperture radar imaging,the rotation angle of the object is required to estimate the phenomenon of the migration through resolution cells and scale the cross range of the image.The phase character of the radar echo is analyzed and a novel method based on phase cancellation for estimating the rotation angle is proposed.In this algorithm,the linear term of the echo phase is eliminated by phase cancellation,then the coefficient of the quadratic phase term is estimated,which is in proportion to the rotation angle.Furthermore,the distribution character of echo energy in the imaging plane is considered and the weighted linear least squares algorithm is used to improve the exactness of the result.Compared with the existing methods,the proposed method behaves more robust and efficient.Simulations with synthetic data and field data confirm the effectiveness of the method.