检索结果-南通市图书馆

Efficient In SAR phase noise reduction via total variation regularization

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2015年第8期58卷 64-76页

作者： LUO XiaoMei WANG XiangFeng suo zhiyong LI ZhenFang State Key Laboratory of Integrated Services Networks Xidian University Department of Electronic Information Engineering Nanchang University Shanghai Key Laboratory of Trustworthy Computing Software Engineering InstituteEast China Normal University National Laboratory of Radar Signal Processing Xidian University

We consider the phase noise filtering problem for Interferometric Synthetic Aperture Radar(In SAR)using a total variation regularized complex linear least squares formulation. Although the original formulation is convex, solving it directly with the standard CVX package is time consuming due to the large problem size. In this paper, we introduce the effective and efficient alternating direction method of multipliers(ADMM) to solve the equivalent well-defined complex formulation for the real and imaginary parts of the optimization *** the iteration complexity and the computational complexity of the ADMM are established in the forms of theorems for our In SAR phase noise problem. Simulation results based on simulated and measured data show that this new In SAR phase noise reduction method not only is 3 orders of magnitude faster than the standard CVX solver, but also has a much better performance than the several existing phase filtering methods.

关键词： interferometric synthetic aperture radar phase noise reduction total variation regularization least squares formulation alternat

Azimuth resolution improvement for spaceborne SAR images with quasi-non-overlapped Doppler bandwidth

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2014年第3期25卷 422-427页

作者： Yanyang Liu Zhenfang Li zhiyong suo Jinwei Li Zheng Bao National Laboratory of Radar Signal Processing Xidian University

The azimuth resolution improvement problem is solved via a coherent combination of synthetic aperture radar （SAR） ima-ges with the quasi-non-overlapped Doppler bandwidth. Prior to the spectra combination, SAR images should be coregistered, while phase biases induced by topography, atmospheric propagation delays and baseline measurement errors should be calibrated. However, the coregistration accuracy suffers from large Doppler decorrelation caused by the quasi-non-overlapped Doppler band-width. Furthermore, the method used to estimate phase biases from interferogram of azimuth prefiltered SAR image pairs wil fail when there is no overlapped spectrum. The fringe simulation and maximum sharpness optimization are adopted to deal with the problems. Accordingly, a novel algorithm to coherently synthesize SAR images is presented. The experiment with the Terra SAR X-band （TerraSAR-X） satel ite data validates the performance of the presented method.

关键词： synthetic aperture radar (SAR) azimuth resolution improvement maximum sharpness optimization fringe simulation.

SAR-GMTI investigation in hybrid along-and cross-track baseline InSAR

在线全文

学校读者我要写书评

暂无评论

Science in China(Series F) 2009年第8期52卷 1399-1408页

作者： suo zhiyong LI ZhenFang BAO Zheng WU JianXin National Key Lab of Radar Signal Processing Xidian University Xi'an 710071 China

A joint-pixel clutter suppression method based on slope compensation is proposed in this paper, In order to eliminate the effect of the terrain interferometric phase caused by the cross-track baseline in hybrid baseline InSAR, the local independent identical distribution of the clutter is satisfied by using the slope compensation technique, and thus the clutter can be suppressed successfully by using the orthogonality of the clutter subspace and the noise subspace. This approach utilizes the information contained in the current pixel as well as in its neighbors, showing robustness to the image coregistration errors. Both the simulated data and the real airborne data are used in proving the validity of the presented approach.

关键词： interferometric synthetic aperture radar (InSAR) along-/cross-track baseline ground moving target indication (GMTI) slope compensation clutter suppression

A novel subset assignment and matching method for DIC measurement of complex deformation in aircraft braking process

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第8期37卷 373-387页

作者： Xin SHI Xiang GUO Tao suo Yingtao YUAN Hongli HE zhiyong REN School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China International Research Laboratory of Impact Dynamics and its Engineering Application Xi’an 710072China Institute of Extreme Mechanics Northwestern Polytechnical UniversityXi’an 710072China Chinese Flight Test Establishment Xi’an 710089China

This paper proposes a measurement method related to the braking deformation of a complex *** the braking process,the deformation of the wheel includes large amounts of movement,vibration,warping,and distortion.A novel subset assignment and correlation method is proposed to measure the complex *** proposed method can greatly improve the accuracy and stability of the calculation of complex deformations by simplifying the complex deformation into translational deformations in logarithmic coordinate *** to the simulation and actual experiments,the proposed method can be utilized to measure the deformations of up to 100%tensile strain under complex *** to the accuracy verification experiment,the error of the proposed method is less than 50 *** results show that the proposed method can effectively carry out structural deformation measurement in the complex motion and deformation *** proposed method has great significance for structural performance analysis and optimization design considering complex motion and deformation.

关键词： Complex deformation Measurement Digital image correlation Aircraft braking Deformation field

On China＇s Economy： A Tentative Research from a Dual Visual Angle

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Business Review 2005年第4期4卷 80-81页

作者： Guibin suo zhiyong Shi Tianjin University

Most economists approach the economy of China from a single visual angle considering it as a special economic modality of transition economy. Based on the analysis from the single visual angle, the paper puts forward a dual visual angle treating China＇s economy as one of both transition and transformation features, and attempts to research it from this dual visual angle.

关键词： China's economy transition and transformation dual visual angle

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

采用自适应字典学习的InSAR降噪方法

西安电子科技大学学报 2016年第1期43卷 18-23页

作者：罗晓梅索志勇刘且根西安电子科技大学综合业务网理论及关键技术国家重点实验室陕西西安710071 南昌大学信息工程学院江西南昌330031 西安电子科技大学雷达信号处理国家重点实验室陕西西安710071 中国科学院劳特伯生物医学成像研究中心广东深圳518055

提出了一种基于字典学习的干涉合成孔径雷达相位降噪算法.首先利用字典学习,建立了干涉相位滤波的优化模型.鉴于该模型非凸难以求解,采用分裂技术和增广拉格朗日框架,获得松弛后的基于l1范数正则化的优化模型,然后引入交替方向乘子法对... 详细信息

提出了一种基于字典学习的干涉合成孔径雷达相位降噪算法.首先利用字典学习,建立了干涉相位滤波的优化模型.鉴于该模型非凸难以求解,采用分裂技术和增广拉格朗日框架,获得松弛后的基于l1范数正则化的优化模型,然后引入交替方向乘子法对松弛后的问题求解,获得最终的相位滤波结果.通过InSAR复相位数据训练字典,从稀疏表达式重建所需的复相位图像.对仿真数据和实测数据的处理显示这种新的InSAR相位降噪方法在残点数、均方误差和边缘完整性保持方面优于现有的经典滤波方法.

关键词： InSAR 相位降噪字典学习 l1范数正则化交替方向乘子法

基于PolInSAR的植被区高精度数字表面模型反演方法

在线全文

学校读者我要写书评

暂无评论

电子与信息学报 2019年第2期41卷 293-301页

作者：解金卫索志勇李真芳王跃锟西安电子科技大学雷达信号处理国家重点实验室西安710071

针对传统方法无法估计电磁波在植被中的穿透深度导致植被数字表面模型(DSM)反演误差较大的问题,该文提出一种高精度DSM估计方法。该方法首先通过极化干涉相干最优中最大化相位差法分离得到电磁波在植被中高、低散射相位中心的干涉相位... 详细信息

针对传统方法无法估计电磁波在植被中的穿透深度导致植被数字表面模型(DSM)反演误差较大的问题,该文提出一种高精度DSM估计方法。该方法首先通过极化干涉相干最优中最大化相位差法分离得到电磁波在植被中高、低散射相位中心的干涉相位。然后提出一种归一化高、低散射相位中心高度随消光系数变化的模型,基于该模型搜索得到电磁波在植被中的最浅穿透深度。最后利用干涉处理方法得到高散射相位中心的高程,将最浅穿透深度补偿到该高程中,从而提升植被区DSM估计精度。利用PolSARpro软件在不同植被种类和不同植被高度下进行仿真试验以及机载全极化数据进行实测数据试验,试验结果表明该方法能有效提高植被区DSM反演精度。

关键词：极化干涉散射相位中心穿透深度数字表面模型

地形高程自适应的星载InSAR图像配准方法

在线全文

学校读者我要写书评

暂无评论

西安电子科技大学学报 2018年第2期45卷 31-36页

作者：张金强索志勇李真芳保铮西安电子科技大学雷达信号处理国家重点实验室陕西西安710071

星载干涉合成孔径雷达在基线较长或观测场景内地形复杂度较高时,地形高程对主辅图像间配准偏移量的影响不可忽略,利用二维二元低阶多项式模型拟合配准偏移量的精度较低,当利用控制点处配准偏移量估计多项式系数时,控制点数量和位置分布... 详细信息

星载干涉合成孔径雷达在基线较长或观测场景内地形复杂度较高时,地形高程对主辅图像间配准偏移量的影响不可忽略,利用二维二元低阶多项式模型拟合配准偏移量的精度较低,当利用控制点处配准偏移量估计多项式系数时,控制点数量和位置分布对估计精度的影响较大.针对上述问题,提出了地形高程自适应的降维图像配准方法.为了追踪主辅图像间配准偏移量随地形高程的变化,提高配准偏移量的拟合精度,提出了包含地形高程项的二维三元一阶多项式模型.利用主辅图像的成像参数和轨道数据计算多项式一次项系数,将需要利用控制点处配准偏移量估计的系数减少为两个常数项系数,提高了估计的稳健性.实测数据处理结果验证了该方法的精确性和稳健性.

关键词：星载干涉合成孔径雷达图像配准地形高程系数估计

圆迹SAR子孔径图像序列联合相关DEM提取方法

在线全文

学校读者我要写书评

暂无评论

系统工程与电子技术 2018年第9期40卷 1939-1944页

作者：张金强索志勇李真芳保铮西安电子科技大学雷达信号处理国家重点实验室陕西西安710071

利用圆迹合成孔径雷达(circular synthetic aperture radar,CSAR)子孔径图像序列提取观测场景地形高程模型(digital elevation model,DEM)时,为了利用保持相关性的一段圆弧内所有子孔径图像之间的相关性信息、提高DEM提取精度,提出了联... 详细信息

利用圆迹合成孔径雷达(circular synthetic aperture radar,CSAR)子孔径图像序列提取观测场景地形高程模型(digital elevation model,DEM)时,为了利用保持相关性的一段圆弧内所有子孔径图像之间的相关性信息、提高DEM提取精度,提出了联合相关法。该方法以保持相关性的一段圆弧内所有子孔径图像之间的联合相关系数作为测度函数,提高了测度函数灵敏度。同时,通过将子孔径图像序列向三维空间投影以校正其几何形变,提高了子孔径图像序列间的相关性。实测数据处理结果及分析验证了所提方法的有效性和精确性。

关键词：圆迹合成孔径雷达子孔径图像序列数字高程模型联合相关