两种星载高分辨宽测绘带SAR系统通道相位误差估计方法

 本文针对星载方位多通道高分辨宽测绘带(HRWS)合成孔径雷达(SAR)系统,提出了两种通道相位误差估计方法:信号子空间比较法和天线方向图法.信号子空间比较法基于信号特征向量张成的空间(即信号子空间)与真实导向矢量张成的空间相同这一特性,得到各通道间的相对相位误差,该方法适用范围广,估计精度高,对系统要求低,且运算量小.天线方向图法结合天线方向图,直接估计通道相位误差,无须特征分解,无须矩阵求逆,运算量小,主要适用于均匀分布的场景.最后利用实测地基数据验证了两种方法的有效性.

Two Channel Phase Error Estimation Methods for Spaceborne HRWS SAR System

Two novel methods,which are referred to as signal subspace comparison method(SSCM)and antenna pattern method(APM),are proposed to estimate the channel phase errors for spaceborne high resolution and wide swath(HRWS)synthetic aperture radar(SAR)system.The SSCM is based on the fact that the space spanned by the signal eigenvectors referred to as the signal subspace is equal to that by the practical steering vectors.One of the great advantages of this method is its low computational burden and high accuracy.Combined with the antenna patterns,the APM estimates the channel phase errors directly without decomposing the covariance matrix,which is suitable for uniform distributed scenes.Finally,the ground-based real data confirms the validity of the two approaches.