基于滤波反投影算法的自旋式综合孔径辐射计分辨率与灵敏度分析  

Resolution and Radiometric Sensitivity Analysis of the Rotating Synthetic Aperture Radiometer Based on Filtered Back Projection Algorithm

作　　者：孙逢林[1,2,3] 张升伟[1,2] 刘浩[1,2] 张成[1,2] 

机构地区：[1]中国科学院微波遥感技术重点实验室,北京100190 [2]中国科学院空间科学与应用研究中心,北京100190 [3]中国科学院大学,北京100190

出　　处：《电子与信息学报》2014年第6期1413-1418,共6页Journal of Electronics & Information Technology

基　　金：气象行业科研专项项目(2009416049)资助课题

摘　　要：针对自旋式稀疏阵列综合孔径微波辐射计近似于极坐标的采样方式下成像算法复杂、系统参数估计困难等问题,该文提出一种基于滤波反投影算法的系统参数估计方法。该方法通过对极坐标下狄拉克采样梳子函数进行1维傅里叶-汉克尔变换得到系统的点扩散函数,并根据点扩散函数主副瓣分解,重点分析了径向与角度方向采样间隔对无混叠视场范围的影响以及主瓣宽度对应的分辨率。该文同时利用滤波反投影算法推导了自旋式稀疏阵列辐射灵敏度的估计方法。数值仿真与实测点源响应函数的一致性表明了该模型的精确性。Thinned rotating arrays of microwave/millimeter wave synthetic aperture imaging radiometer result in polar like visibility samplings where complex image reconstruction algorithms are in need and it is tough work to estimate important system parameters. To address this problem, a new method based on filtered back projection algorithm is proposed. In this approach, the system Point Spread Function （PSF） is obtained by 1-D Fourier-Bessel （Hankel） transforming from Dirac comb function. Spatial resolution and alias-free of view affected by radial and angular sampling intervals are analyzed by decomposing PSF into main lobe and a series of ring lobes. A new formulation to estimate the radiometric sensitivity of thinned rotating arrays by filtered back projection algorithm is also proposed. The consistency between the numerical and measured point spread function indicates that the proposed model is accurate.

关 键 词：自旋式综合孔径成像辐射计 滤波反投影算法 傅里叶-汉克尔变换 空间分辨率 辐射灵敏度 

分 类 号：TP722.6[自动化与计算机技术—检测技术与自动化装置]