一种SAR成像中的非均匀采样重构方法

Non-uniform Reconstruction Method in SAR Imaging

方位向非均匀采样是合成孔径雷达获取高分辨率图像的瓶颈之一,它导致图像的方位向分辨率、峰值旁瓣比和积分旁瓣比恶化,成像质量变差。提出了具有较高补偿精度和计算效率的非周期内插零的方法,在两个采样点之间插入非周期的零值,利用快速傅里叶变换在频域实现均匀采样重构,分析了插值倍数以及非周期的残留误差对图像指标的影响。仿真结果验证了方法的有效性。

Non-uniform sampling in azimuth is one of the bottle-necks in high resolution synthetic aperture radar （SAR） imaging.It results in low quality image with degraded resolution,peak side lobe ratio （PSLR） and integrated side lobe ratio （ISLR）.Nonperiodic interpolating zeros method with high precision and efficiency was proposed.It interpolated nonperiodic zeros between two samples and reconstruct uniform spectrum in frequency domain by Fast Fourier Transform （FFT）.The image performance affected by interpolating multiple and nonperiodic residual error was analyzed.Finally,simulations demonstrate the validity.