摘要
双基星载高分辨率宽测绘带合成孔径雷达系统(HRWS-SAR)的方位向信号普遍为非均匀采样,重构其均匀采样信号或多普勒频谱是成像处理的关键步骤。文中将方位照射时间内时变的发射接收距离比近似为常数,利用双基系统与单基系统方位向通道间传递函数的等效关系,建立了一般双基构型星载HRWS-SAR系统的方位向信号模型,构建了方位向信号重构的最小二乘算法,利用传递函数矩阵的Vandermonde矩阵表示有效降低算法复杂度,并给出了重构性能指标信噪比缩放因子及方位模糊比的计算公式。文中对几种典型双基构型的星载HRWS-SAR系统进行方位向信号重构仿真,结果表明最小二乘算法能较高性能的重构出方位向信号的多普勒频谱。
In bistatic spaceborne high resolution wide swath SAR system （ HRWS-SAR）, the azimuth reconstruction to obtain the uniform sampling signal or Doppler spectrum is a key step in image processing, for the azimuth signal is generally non-uniform sampling. In this paper, the variant transmitting distance to receiving radio approximated at a constant, the equivalence is deduced between the bistatic and monostatic SAR azimuth interchannel transfer functions, and the azimuth signal model in spaceborne HRWS-SAR with general bistatic configuration is established. Furthermore, the least square algorithm is proposed to reconstruct the azimuth signal, the complexity of the algorithm is effectively reduced by the Vandermonde matrix representation of transfer function matrix, and the formula for the signal noise ratio （SNR） scaling factor and the azimuth ambiguity signal ratio （AASR） are given to measure the reconstruction performance. The azimuth reconstruction is simulated in several spaceborne HRWS鄄SAR systems with typical bistatic configuration, the results show that the azimuth Doppler spectrum can be reconstructed with high performance by the least square algorithm.
出处
《现代雷达》
CSCD
北大核心
2017年第10期36-42,48,共8页
Modern Radar
基金
安徽省自然科学基金资助项目(1508085MF119)
