一种基于压缩感知的高分辨率宽测绘带合成孔径雷达成像算法

HRWS SAR Imaging Based on Compressed Sensing

针对高分辨率宽测绘带合成孔径雷达(High Resolution Wide Swath Synthetic Aperture Radar,HRWSSAR)在俯仰向波束形成受地面目标高程影响造成增益损失以及在方位向非均匀采样造成模糊的问题,文中提出了一种基于压缩感知(Compressed Sensing,CS)技术的HRWS SAR成像算法。根据SAR系统和平台参数建立精确的观测模型后,通过求解1优化问题直接准确地估计出了在地面高程变化影响下的目标来波方向(Direction ofArrival,DOA)并重建了非均匀采样下的方位向观测场景,从而实现了HRWS SAR在俯仰向和方位向的非模糊成像。仿真结果表明了本文算法的有效性。

Compressed Sensing（CS） is introduced into High Resolution Wide Swath Synthetic Aperture Radar（HRWS SAR） imaging.In the HRWS SAR system,a small antenna for transmitting waveform and multiple antennas both in range and azimuth for receiving echoes is used.The data of multiple elevation antennas after range compression are used to estimate direction of arrival of targets via CS,and the adaptive beamforming in elevation is achieved accordingly,thus avoiding the gain loss of Scan-on-Receive（SCORE） algorithm in the presence of topographic height change.The effective phase centers of the system are nonuniformly distributed,which cause Doppler ambiguities under traditional SAR imaging algorithms.Azimuth reconstruction based on CS can resolve this problem via precisely modeling the nonuniform sampling.