基于SP-LSQR的综合孔径辐射成像方法  

Imaging Method of Synthetic Aperture Interferometric Radiometers Based on Subspace Preconditioned LSQR

作　　者：杨真乙 杨晓城[1,2] 阎敬业[2,3] 武林 蒋明峰[1] YANG Zhen-yi;YANG Xiao-cheng;YAN Jing-ye;WU Lin;JIANG Ming-feng(School of Information Science and Technology,Zhejiang Sci-Tech University,Hangzhou 310018,China;State Key Laboratory of Space Weather,Chinese Academy of Sciences,Beijing 100190,China;National Space Science Center,Chinese Academy of Sciences,Beijing 100190,China)

机构地区：[1]浙江理工大学信息学院,杭州310018 [2]中国科学院空间天气学国家重点实验室,北京100190 [3]中国科学院国家空间科学中心,北京100190

出　　处：《微波学报》2023年第2期16-20,共5页Journal of Microwaves

基　　金：国家重点实验室专项基金资助项目(202217);国家自然科学基金(61672466,620115300130);浙江省自然科学基金-数理医学学会联合基金重点项目(LSZ19F010001);浙江省科技厅重点研发项目(2020C03060)。

摘　　要：综合孔径微波辐射计是被动微波遥感领域中一种重要的探测器。综合孔径辐射计成像反演过程在数学上是病态的反问题,传统正则化方法虽然能够有效克服其病态性,但重构误差较大、对干扰噪声鲁棒性不强。与传统正则化方法相比,最小二乘Q-R矩阵(Least Square Q-R matrix,LSQR)分解算法具有计算精度高、数值稳定性好等优点,但收敛速度不够快。对此,文中提出利用子空间预处理LSQR(Subspace Preconditioned LSQR,SP-LSQR)算法进行综合孔径辐射计反演成像,提高收敛速度。仿真结果表明:与Tikhonov正则化和带限正则化相比,SP-LSQR方法不仅可以降低重构误差,而且对干扰噪声的鲁棒性更强。此外,与LSQR方法相比,SP-LSQR方法在不降低成像反演精度的情况下,有效提高了计算效率。Synthetic aperture interferometric radiometers(SAIRs)are an important detector in the field of passive microwave remote sensing.The imaging inversion process in SAIRs is an ill-conditioned inverse problem mathematically.Although the traditional regularization methods can effectively overcome its ill-condition,there are the problems of large reconstruction errors and poor robustness to interference noise.Compared with traditional regularization methods,the LSQR iterative method has the advantages of high calculation accuracy and good numerical stability.However,the convergence speed for the LSQR method is not fast enough.With regards to this,a subspace preconditioned LSQR(SP-LSQR)decomposition algorithm is proposed to perform the inversion imaging of SAIRs so as to improve the convergence speed.The simulation results show that compared with the Tikhonov and band-limited regularizations,the SP-LSQR method can not only reduce the reconstruction error,but also be more robust to interference noise.In addition,the SP-LSQR method effectively improves the computational efficiency without reducing the accuracy of the inversion results,compared with the LSQR method.

关 键 词：被动微波遥感 综合孔径辐射计 正则化 子空间预处理最小二乘Q-R 矩阵分解算法 

分 类 号：P237[天文地球—摄影测量与遥感]