一种新的步进频MIMO-SAR带宽合成的处理方法

针对步进频多发多收合成孔径雷达通道间存在相位误差影响距离带宽合成的问题，提出了一种基于回波数据的通道误差估计的两步处理方法．首先，提出一种距离向相位调整的对比度增强算法来估计子带内高阶相位误差，通过补偿得到聚焦的子带信号; 接着，对子带信号进行上采样和频谱移动，建立了一种旁瓣平衡模型，并推导得到旁瓣偏离率和常数相位误差的关系表达式，将实测数据的旁瓣偏离率代入便可计算得到通道间的常数相位误差．通过以上两步估计补偿后，在频率域完成步进频信号带宽合成，实现分辨率的提升．对实测数据进行处理，得到0.06m的距离分辨率，并对补偿前后合成孔径雷达成像结果进行对比分析，验证了该方法的正确性和高效性．

Novel two-step method of bandwidth synthesis for SF-MIMO-SAR

For stepped frequency multiple-input and multiple-output synthetic aperture radar (SF-MIMO-SAR), the result of bandwidth synthesis in range is affected by channel phase mismatch. In order to solve this problem, this paper proposes a two-step error estimation method based on echo data. First, aiming to optimize the focus sub-band image, phase adjustment by contrast enhancement algorithm is modified to estimate high-order phase errors in range. Then, the sub-band signal is up-sampled, shifted, and the model of balanced side-lobe is proposed to calculate and compensate the constant phase error. After the above compensation, we will obtain the synthesized SAR image with the resolution of 0.06 meter in range, and experimental data demonstrate the effectiveness of the proposed method.