方位多相位中心SAR信号重建误差分析

就方位多相位中心(Azimuth Multiple-Phase-Center,AMPC)合成孔径雷达(Synthetic Aperture Radar,SAR)系统的阵列误差对信号重建性能的影响进行分析。将阵列误差建模为随机过程,结合最小二乘(Least-Square,LS)算法,推导了AMPC SAR误差功率谱的解析表达式,进而得到了AMPC SAR的信噪比与方位模糊比的解析表达式。仿真实验验证了理论分析的正确性。分析指出,随着系统脉冲重复频率的升高,有必要通过减小重建系数以实现重建性能的提升。分析方法与结果对AMPC SAR系统设计以及图像质量预估提供有效支撑。

Reconstruction error of azimuth multiple-phase-center

Influence of array errors of azimuth multiple-phase-center (AMPC) synthetic aperture radar (SAR) on signal reconstruction performance is investigated. The array errors are modeled as stochastic process. In combination with least-square (LS) algorithm, we derive the analytical expression of the reconstruction error power spectrum. Then, we obtain the analytical expressions of signal to noise ratio (SNR) and azimuth ambiguity to signal ratio (AASR). Experiment results confirm the validity of the theoretical analyses. Analytical results indicate that the image quality of AMPC SAR can be improved by decreasing the reconstruction coefficient when pulse repetition frequency (PRF) increases. The approaches and results benefit system design and image quality evaluation of AMPC SAR.