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A NEW METHOD OF FrEQUENCY-HOppING(FH) SIGNAL DETECTION

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Journal of Electronics(China) 2011年第4期28卷 468-473页

作者： Zeng Yu liu Xueqian Li Ou(information and engineering {3.,information and engineering Institute,zhengzhou 450002,China) information and engineering Institute Information and Engineering University Zhengzhou China zhengzhou China

A new Frequency-Hopping(FH) signal detection method is *** from pre-vious methods which need to monitor the total band,it can monitor p.r. of the band and decrease the range of the *** to this method,a new detection model is set and the computation formulas of the detection probability and false-alarm probability are *** p.r.meters of a VHF radio are used to prove the validity of the *** results show that this method can de-crease the range of the bandwidth and detect the FH signal with some penalty on the SNr and signal loss.

关键词： Frequency-Hopping(FH) Detection Monitor Interception Channelized radiometer

A relationship between the nonexistence of generalized bent functions and class groups

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Science China Mathematics 2010年第1期53卷 213-222页

作者： liu FengMei 1,& YUE Qin 21 Dep.r.ment of information research,College of information engineering,information engineering university,zhengzhou 450002,China 2 Dep.r.ment of Mathematics,Nanjing university of Aeronautics and Astronautics,Nanjing 210016,China 1. Dep.r.ment of information research College of Information Engineering Information Engineering University Zhengzhou 450002 China2. Department of Mathematics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

A new result on the nonexistence of generalized bent functions is presented by using prop.r.ies of the decomposition law of primes in cyclotomic fields and prop.r.ies of solutions of some Diophantine equations. At the same time,a method is given which can be used to simplify the known results. Then we give the bounds and the meaning in algebraic number theory of the p.r.meters in our results.

关键词： generalized bent function integral basis class group genus theory

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一种宽范围高精度的前向载波频偏估计算法

系统仿真学报 2008年第18期20卷 4968-4970页

作者：刘世刚葛临东郑州解放军信息工程大学郑州450002

前向载波频偏估计算法的捕获范围和估计精度是一对矛盾。针对这一问题,提出一种低计算复杂度的宽范围高精度前向载波频偏估计算法。算法的基本思想是:首先,利用相邻码元判决点处的相位差粗略估计载波频偏,以便获得宽的捕获范围;然后,利... 详细信息

前向载波频偏估计算法的捕获范围和估计精度是一对矛盾。针对这一问题,提出一种低计算复杂度的宽范围高精度前向载波频偏估计算法。算法的基本思想是:首先,利用相邻码元判决点处的相位差粗略估计载波频偏,以便获得宽的捕获范围;然后,利用高时延自相关函数精细估计载波频偏,以便获得高的估计精度。详细描述了算法的数学表达,并对其性能进行了分析。最后的仿真数据证明,该算法对于载波频偏的宽范围高精度估计,确实具有较高的实用价值。

关键词：短突发信号前向结构载波同步频偏估计相位折叠

基于波束空间的极化域-空域联合谱MUSIC算法

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数据采集与处理 2010年第S1期25卷 28-31页

作者：刘扬吴瑛信息工程大学信息工程学院郑州450002

极化敏感阵列可以获取到空间电磁信号的极化信息,具有优越的系统性能,可以更充分地利用信号中包含的信息。极化域-空域联合谱MU S IC算法是一种高性能的算法,但是在两信号参数相差不大,尤其是极化角度接近时无法分辨,在低信噪比、干扰... 详细信息

极化敏感阵列可以获取到空间电磁信号的极化信息,具有优越的系统性能,可以更充分地利用信号中包含的信息。极化域-空域联合谱MU S IC算法是一种高性能的算法,但是在两信号参数相差不大,尤其是极化角度接近时无法分辨,在低信噪比、干扰信号功率较大时算法性能明显下降,本文将波束空间预处理的方法应用该算法,阵列的抗干扰能力得到了提高,实验证明新算法的有效性。

关键词：极化敏感阵列信号处理极化域-空域联合谱多参数估计微分进化

Image universal steganalysis based on best wavelet packet decomposition

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Science China(information Sciences) 2010年第3期53卷 634-647页

作者： LUO XiangYang1,2, liu FenLin1, YANG ChunFang1 & WANG DaoShun2 1information Science and Technology Institute, zhengzhou 450002, China 2De{3.ment of Computer Science and Technology, Tsinghua university, Beijing 100084, China 1. information Science and Technology Institute Zhengzhou 450002 China2. Department of Computer Science and Technology Tsinghua University Beijing 100084 China

Based on the best wavelet packet decomposition of images, a new universal steganalysis method with high detection correct ratio is proposed. First, the best wavelet packet decomposition of image based on the Shannon entropy information cost function is made. Second, high order absolute characteristic function moments of histogram extracted from the coefficient subbands obtained by best wavelet packet decomposition are regarded as features. Finally, these features are processed and a back-propagation (Bp) neural network is designed to classify original and stego images. Three different steganalysis algorithms for three different cases of background and application condition are presented. To validate the p.r.ormance of the proposed method, a series of exp.r.ments are made for six kinds of typical steganography methods, i.e. LSB, LTSB, pMK, Jsteg, F5 and JpHide. results show that, the average detection accuracy of the proposed method exceeds at least 6.4% and up to 15.4% and has a better universal p.r.ormance than its closest competitors. Furthermore, the proposed method can provide reference for designing the pattern recognition and classification algorithm based on best wavelet packet decomposition.

关键词： steganography digital images universal steganalysis best wavelet packet decomposition Bp neural network

A Nonp.r.metric Sinusoid Detector with CFAr in White Noise

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A Nonparametric Sinusoid Detector with CFAR in White Noise

Handwriting Digit recognition Based on Extension engineering

第八届国际信号处理国际会议

作者： Shuangping liu Dongling Zhang Zhigang Wang Institute of information engineering information engineering university zhengzhou Henan 450002 p. r. China

＜正＞A nonp.r.metric detector called SFCD （Segments Frequency Checking Detector）, the pfa （false alarm probability） of which is constant and can be easily calculated, is put forward for the problem of detecting a sinusoid of unknown amplitude, frequency and phase in complex white Gaussian or non-Gaussian noise of unknown variance and probability distribution. The decision will be made on the basis of a statistical hypothesis test vector that is composed of a group of discrete frequency bins, which are scaled coarse frequency estimations of hypothetical sinusoid in all length-equal and non-overlapping segments of signal samples. A sinusoid is believed to exist in the received signal if all the absolute values of the difference between the first element and the others of the vector equal zero of one. The basic principle of the proposed algorithm in this pap.r.will be introduced on condition of white Gaussian noise. The pfa and pd （detecting probability） are proved independent of the probability distribution of white noise by Monte Carlo simulation, although the p.r.ormance of pd is shown to deteriorate less than 4 dB comp.r.d with optimal p.r.metric detector as far as samples length of 256 and pfa of 1e-4 is concerned.

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Handwriting Digit Recognition Based on Extension Engineering

A NEW TWO-DIMENSIONAL SIGNAL DECOMpOSITION SCHEME USING THE EXTrEME-LIFTING SCHEME

2009中国控制与决策会议

作者： Huimin Xiao,Chen liu information School,Henan university of Finance & Economics,{3.

The complicated training algorithm is needed in the traditional handwriting digits recognition,the complexity of algorithm is very high,and the expansibility to huge database is *** this pap.r.the handwriting digit is recognized by means of the extension *** classical domains and the extensional domains of handwriting digit character are *** integrated correlative degrees of the measuring digits and 10 basic digits are calculated and handwriting digits are classified and recognized. According to the calculated correlative degrees and the recognized results,extension engineering is an effective method to handwriting digit recognition..

关键词： Handwriting digit recognition Extension engineering Classification Supp.r. vector machine

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Journal of Electronics(China) 2001年第2期18卷 105-112页

作者： liu Baofang ping Xijian Deng Guanglin Shao Meizhen(Dept. of Info. Sci., university of information {3., zhengzhou 450002)(p.O.Box 1965, Beijing 100091) Dept.of Info.Sci. University of Information EngineeringZhengzhou 450002 p.O.Box 1965 Beijing 100091

This pap.r.discusses the signal decomposition method using the extreme-lifting scheme and two two-dimensional decomposition schemes: sep.r.ble one-dimensional scheme and two-dimensional scheme with quincunx sampling. The structure of the relation "～" between Ex and Ey of these two schemes is symmetrical and both these two schemes have shortcomings)An unsymmetrical scheme of the extreme-lifting scheme is proposed in this pap.r. which canbe directly used to decompose two-dimensional image and can get better decomposition result than the two schemes with little computation cost.

关键词： Signal decomposition Min-lifting scheme Quincunx sampling Lifting scheme

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基于遗传算法的不完备信息表约简方法

计算机工程与应用 2005年第22期41卷 174-176页

作者：孙晶晶刘镔刘粉林解放军信息工程大学信息工程学院郑州450002

粗糙集理论是一种较新的处理模糊和不确定知识的软计算工具。针对粗糙集理论中不完备信息系统的容差关系的一种改进模型,结合遗传算法的全局优化和隐含并行性的特性,给出了一种不完备信息系统属性约简方法,经仿真实验知该算法是有效的,... 详细信息

粗糙集理论是一种较新的处理模糊和不确定知识的软计算工具。针对粗糙集理论中不完备信息系统的容差关系的一种改进模型,结合遗传算法的全局优化和隐含并行性的特性,给出了一种不完备信息系统属性约简方法,经仿真实验知该算法是有效的,能得到不同概念层次的所有相对最小约简。

关键词：粗糙集不完备信息系统遗传算法相对最小约简