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A WEIGHTED FEATURE REDUCTION METHOD FOR POWER SPECTRA OF radar HRRPS

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Journal of Electronics(china) 2006年第3期23卷 365-369页

作者： Du Lan Liu Hongwei Bao Zheng Zhang Junying National laboratory of radar Signal Processing Xidian University Xi＇an 710071 China

Feature reduction is a key process in pattern recognition. This paper deals with the feature reduction methods for a time-shift invariant feature, power spectrum, in radar Automatic Target Recognition (RATR) using High-Resolution Range Profiles (HRRPs). Several existing feature reduction methods in pattern recognition are analyzed, and a weighted feature reduction method based on Fisher's Discriminant Ratio (FDR) is proposed in this paper. According to the characteristics of radar HRRP target recognition, this proposed method searches the optimal weight vector for power spectra of HRRPs by means of an iterative algorithm, and thus reduces feature dimensionality. Compared with the method of using raw power spectra and some existing feature reduction methods, the weighted feature reduction method can not only reduce feature dimensionality, but also improve recognition performance with low computation complexity. In the recognition experiments based on measured data, the proposed method is robust to different test data and achieves good recognition results.

关键词： radar Automatic Target Recognition (RATR) High-Resolution Range Profile (HRRP) Power spectrum Feature reduction Fisher's Discriminant Ratio (FDR)

A MTRC correction algorithm in Bistatic ISAR

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A MTRC correction algorithm in Bistatic ISAR

基于归一化互相关成像条件的GPR逆时偏移成像

2009 2nd Asian-Pacific Conference on Synthetic Aperture radar（APSAR2009）

作者： Zhu Xiao-peng 1 Zhang Qun 1 2 Zhu Ren-fei 1 Li Hong-wei 1(1.Inst.of Telecommunication Engineering AFEU Xi’an 710077 2.key laboratory of Wave Scattering and Remote Sensing Information(Ministry of Education) Fudan University Shanghai 200433)

In conventional ISAR system,when the requested resolution of radar is high,while the size of target is large,it will cause the Migration Through Resolution Cell（MTRC）,it will also exist the same problems in Bistatic ISAR *** paper analyzes and discusses the reason of causing MTRC particularly in the module of Bistatic ISAR,and compares it with the situation in Mono ISAR *** then a correction algorithm based on keystone transformation is presented in the paper,which eliminates the MTRC in the targer imaging,Finally,some simulation results are given to validate the validity of the algorithm.

关键词： Bistatic ISAR Migration Through Resolution Cell(MTRC) keystone transformation

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中南大学学报（自然科学版） 2018年第5期49卷 1221-1227页

作者：陈德鹏戴前伟冯德山王洪华张彬中南大学地球科学与信息物理学院湖南长沙410083 有色金属成矿预测与地质环境监测教育部重点实验室湖南长沙410083 桂林理工大学地球科学学院广西桂林541004

针对基于零时刻成像条件的探地雷达(GPR)逆时偏移精度低、难以对复杂结构进行高精度成像的缺点,将归一化互相关成像条件应用于GPR叠前逆时偏移成像。从二维GPR电磁波方程出发,采用基于完全匹配层(PML)边界条件的时域有限单元法(FETD)模... 详细信息

针对基于零时刻成像条件的探地雷达(GPR)逆时偏移精度低、难以对复杂结构进行高精度成像的缺点,将归一化互相关成像条件应用于GPR叠前逆时偏移成像。从二维GPR电磁波方程出发,采用基于完全匹配层(PML)边界条件的时域有限单元法(FETD)模拟电磁波正向和逆向传播,采用归一化互相关成像条件获取叠前逆时偏移的偏移结果,将空间高通滤波用于压制互相关过程中产生的低频噪声,然后编制相应的GPR叠前逆时偏移程序。在此基础上,建立2个复杂的GPR模型,利用基于归一化互相关成像条件的GPR逆时偏移程序进行计算,并与基于零时刻成像条件的GPR逆时偏移剖面进行对比。研究结果表明:与基于零时刻成像条件的GPR逆时偏移剖面相比,基于归一化互相关成像条件的GPR叠前逆时偏移剖面能更清晰地反映异常体空间形态和内部结构信息,其分辨率和成像精度更高。

关键词：探地雷达逆时偏移归一化互相关成像条件零时刻成像条件

基于Transputer的PPI显示仿真的研究

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微机发展 1997年第4期7卷 25-27页

作者：李春洪张文林余少波海军军训器材研究所江苏省南京市210015 海军工程学院计算机系湖北省武汉市430033

本文提出了一种基于Transputer的自达显示的仿真方法，给出了系统的结构和原理，并对其中的关键问题和难点提出了解决办法．实践证明，这种方法是有效的．

关键词： Transputer 仿真雷达显示仿真 PPI

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计算机技术在电子装备测试系统中的应用研究

装备指挥技术学院学报 2003年第6期14卷 84-86页

作者：王斌赵丽莉李增有 91550部队 220所辽宁大连116023 91550部队 240所辽宁大连116023

在现代测试技术快速发展的今天,计算机已成为武器装备自动测试系统中不可缺少的重要组成部分.高性能的计算机软件技术更是构建智能型、集成化自动测试系统的关键所在.分析了先进的软件技术在自动测试系统中的应用状况;并以导弹地面测量... 详细信息

在现代测试技术快速发展的今天,计算机已成为武器装备自动测试系统中不可缺少的重要组成部分.高性能的计算机软件技术更是构建智能型、集成化自动测试系统的关键所在.分析了先进的软件技术在自动测试系统中的应用状况;并以导弹地面测量雷达系统为例,具体介绍了利用系统仿真方法进行装备自动检测的技术实现.

关键词：电子装备武器装备自动测试系统计算机软件技术系统仿真

Object recognition of ladar with support vector machine

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Object recognition of ladar with support vector machine

Error analysis of non-spherical raindrops on precipitation measurement

Photonics Asia 2004;Sensors and Imaging

作者： Jian-Feng Sun Qi Li Qi Wang National key laboratory of Tunable Laser Technology, Institute of Opto-Electronic of Harbin Institute of Technology, Harbin, china, 150001

Intensity, range and Doppler images can be obtained by using laser radar. Laser radar can detect much more object information than other detecting sensor, such as passive infrared imaging and synthetic aperture radar (SAR). so it is well suited as the sensor of object recognition. Traditional method of laser radar object recognition is extracting target features, which can be influenced by noise. In this paper, a laser radar recognition method-Support Vector Machine is introduced. Support Vector Machine (SVM) is a new hotspot of recognition research after neural network. It has well performance on digital written and face recognition. Two series experiments about SVM designed for preprocessing and non-preprocessing samples are performed by real laser radar images, and the experiments results are compared.

关键词： support vector machine, laser radar, target recognition

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Journal of Shanghai University(English Edition) 2011年第2期15卷 92-95页

作者：解亚楠周星里杨正得 key laboratory of Specialty Fiber Optics and Optical Access Networks School of Communication and Information Engineering Shanghai University

radar cross section （RCS） of non-sphericai raindrops is calculated by using the software CST based on finite integral method and compared with RCS of spherical raindrops. The revised factor of non-spherical raindrops is obtained. The radar reflectivity with precipitation change of four distribution models of M-P, Gamma, JD and JT combining the revised factor is gotten using trapezoidal integration. When the infuence of non-spherical raindrops is considered, the accuracy of precipitation measurement of four distribution models can be separately improved 8.77%, 8.47%, 10.53% and 8.04% in the case of rain intensity is 100 mm/h.

关键词： radar cross section (RCS) the revised factor radar reflectivity accuracy of precipitation measurement

A change detection algorithm based on object feature for SAR image

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A change detection algorithm based on object feature for SAR...

High-precision,fast DEM reconstruction method for spaceborne InSAR

2009 2nd Asian-Pacific Conference on Synthetic Aperture radar（APSAR2009）

作者： Xiaohua Zhang Hongfeng Li Licheng Jiao Institution of Intelligent Information Processing and key laboratory of Intelligent Perception and Image Understanding of Ministry of Education Xidian University Xi’an 710071 china

In the detection of change objects of SAR images,regard to the images containing high intensity noise,traditional methods will produce a considerable false *** paper presents a new method of change detection based on directional *** measure is proposed to suppress noises and brighten object *** region blocks which contain changing objects are extracted according to the difference map of direction ***, changed objects can be obtained using the OTSU threshold method for each region *** experimental results on SAR images demonstrate the efficiency and accuracy of the proposed method.

关键词： Change detection direction measure region blocks multi-threshold and object

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Science china(Information Sciences) 2011年第11期54卷 2400-2410页

作者： WANG QingSong,HUANG HaiFeng,DONG Zhen,YU AnXi & LIANG DianNong National University of Defense Technology,Changsha 410073,china 1. National University of Defense Technology Changsha 410073 China

The primary objective of the spaceborne interferometric synthetic aperture radar (InSAR) system is to develop a consistent global digital elevation model (DEM).The improvement of the processing speed in global interferometry missions while maintaining the accuracy is becoming an important *** reconstruction is the most time-consuming step in the data processing required for spaceborne *** on a DEM reconstruction principle analysis,we exploited two basic characteristics of the mapping relation between the interferometric phase and 3-D position of target ***,the relation between the 3-D position of the target point and the interferometric phase can be approximated using ***,the corresponding polynomials change slowly in the local SAR ***,we verified the foundations of the two mentioned characteristics ***,we proposed a fast method of DEM reconstruction based on this *** descriptions of the step and key parameters of the fast algorithm are ***,the repeat-pass interferometric data obtained using TerraSAR-X was used to test the presented *** experimental results showed that a significant reduction in computation time is achieved with only a small loss in *** effectiveness and correctness of the proposed method were also validated.

关键词： interferometric synthetic aperture radar (InSAR) spaceborne SAR DEM reconstruction fast algorithm