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Pair-wise error probability and its Chernoff upper bound for unitary space-time code

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Science china(Information Sciences) 2010年第8期53卷 1613-1621页

作者： ZHANG DaPeng 1,2 , LIU Ju 1 , XU HongJi 1 & JI Hui 1 1 School of Information Science and Engineering, Shandong university, Jinan 250100, china 2 state key laboratory of integrated services networks, xidian university, xi’an 710071, china School of Information Science and Engineering Shandong University Jinan China state key laboratory of integrated services networks Xidian University Xi’an China

Unitary space-time code is ideally suited for rapid fading scenarios as it can operate well without channel state information (CSI), which is of vital significance for improving the effectivity and reliability of wireless communication systems. Pair-wise error probability (PEP) is an important factor for studying the reliability of a communication system. However, the existing scheme only gives the final result of PEP and the corresponding Chernoff upper bound (CUB) is obtained through magnification, which is not of universal significance for this kind of problems. In this paper, we employ the log-likelihood ratio of probability density functions of the received signals conditioned on the two possibly transmitted signals and by virtue of moment generating function we give the details in deriving the final precise residue expression for PEP and its CUB. At last, we verify the above results by simulations.

关键词： multiple-input multiple-output space-time code unitary space-time code pair-wise error probability Chernoff upper bound

Construction of nonbinary quantum cyclic codes by using graph method

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Science in china(Series F) 2005年第6期48卷 693-702页

作者： LIU Tailin1,2,3, WEN Qiaoyan1 & LIU Zihui4 1. School of Science, Beijing university of Posts and Telecommunications, Beijing 100876, china 2. state key laboratory of integrated services network, xidian university, xi’an 710071,china 3. Shandong Finance Institute, Jinan 250014, china 4. School of Mathematical Sciences, Peking university, Beijing 100871, china School of Science Beijing University of Posts and Telecommunications Beijing China state key laboratory of integrated services network Xidian University Xi’an China Shandong Finance Institute Jinan China School of Mathematical Sciences Peking University Beijing China

Using the graph method proposed by Schlingemann and Werner, this paper introduces a technique to construct nonbinary quantum cyclic codes and provides a specific example. We also construct the quantum codes [[8, 2, 4]... 详细信息

关键词： nonbinary quantum stabilizer codes quantum cyclic codes

Price-based interference avoidance game in the Gaussian interference channel

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Science china(Information Sciences) 2012年第2期55卷 301-311页

作者： JING ZhenHai1,BAI BaoMing1 & MA xiao2 1state key laboratory of integrated services networks,xidian university,xi'an 710071,china 2Department of Electronics and Communication Engineering,Sun Yat-sen university,Guangzhou 510275,china state key laboratory of integrated services networks Xidian University Xi’an China Department of Electronics and Communication Engineering Sun Yat-sen University Guangzhou China

This paper considers a distributed interference avoidance problem employing frequency assignment in the Gaussian interference channel(IC).We divide the common channel into several sub-channels and each user chooses one sub-channel for transmission in such a way that the total interference in the IC is *** mechanism named interference avoidance in this paper can be modeled as a competitive game *** a completely autonomous distributed iterative algorithm called distributed interference avoidance algorithm(DIA)is adopted to achieve the Nash equilibrium(NE)of the *** to the self-optimum,the DIA is a sub-optimal ***,through introducing an optimal compensation(or price)into the competitive game model,we successfully develop a compensation-based game model to approximate the optimal interference avoidance ***,an optimal algorithm called iterative optimal interference avoidance algorithm(IOIA)is proposed to reach the optimality of the interference avoidance *** analyze the implementation complexity of the proposed algorithm which is only O(N),with N standing for the number of users in the *** also give the proof on the convergence of the proposed *** performance upper bound and lower bound are derived for the IOIA *** simulation results show that the IOIA does reach the optimality under the condition of interference avoidance mechanism.

关键词： interference channel interference avoidance game theory

A NEW EFFICIENT ID-BASED PROXY BLIND SIGNATURE SCHEME

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Journal of Electronics(china) 2008年第2期25卷 226-231页

作者： Ming Yang Wang Yumin state key Lab of integrated Service network Xidian University Xi＇an 710071 China

In a proxy blind signature scheme,the proxy signer is allowed to generate a blind signature on behalf of the original signer. The proxy blind signature scheme is useful in several applications such as e-voting,e-payment,etc. Recently,Zheng,et al. presented an IDentity(ID) -based proxy blind sig-nature. In this paper,a new efficient ID-based proxy blind signature scheme from bilinear pairings is proposed,which can satisfy the security properties of both the proxy signatures and the blind signature schemes. Analysis of the scheme efficiency shows that the new scheme is more efficient than Zheng,et al.'s scheme. The proposed scheme is more practical in the real world.

关键词： Blind signature Proxy signature Bilinear pairing

Fair Non-Repudiation for Web services Transactions

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Wuhan university Journal of Natural Sciences 2010年第5期15卷 385-392页

作者： SU Ruidan,FU Shaofeng,ZHOU Lihua key laboratory of Computer network and Information Security of the Ministry of Education,xidian university,xi’an 710071,Shaanxi,china key laboratory of Computer network and Information Security of the Ministry of Education Xidian University Xi’an Shaanxi China

To safeguard the interests of transacting parties,non-repudiation mechanisms need to assure fairness and *** non-repudiation service currently implemented usually does not consider the requirement of fairness and the fair non-repudiation protocols to date can not be suitably applied in real environment due to its complex *** paper discusses the transaction-oriented non-repudiation requirement for Web services transaction,analyzes the constraints of the traditional model for the available fair non-repudiation protocols and designs a new Online-TTP fair non-repudiation *** new protocol provides a fair non-repudiation solution to secure Web services transactions and can be embedded into a single Web service *** protocol adopts evidence chained to decreasing the overhead of evidence verification and management and alleviates the overhead of certificate revocation checking and time-stamp generation for *** protocol has strong fairness,timeliness,efficiency and practicability.

关键词： fair non-repudiation Web services transaction evidence chaining timeliness

A novel method for the improvement of power efficiency in high peak-to-average-power ratio communication systems

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Science china(Information Sciences) 2010年第8期53卷 1697-1702页

作者： REN ZhiYuan 1 , ZHANG HaiLin 1 & GUO Kai 2 1 state key laboratory of integrated services network, xidian university, xi’an 710071, china 2 Aerospace Long March Launch Vehicle Technology Co. Ltd., Beijing 100076, china state key laboratory of integrated services network Xidian University Xi’an China Aerospace Long March Launch Vehicle Technology Co. Ltd. Beijing China

To solve the problem of low power efficiency of power amplifiers (PA) in the high peak-to-averagepower ratio (PAPR) communication system, a novel signal decomposed amplifier structure has been proposed in order to decrease the energy consumption and increase the power efficiency of PA. The high PAPR signal can be decomposed into several low PAPR branch signals, linearized and amplified in parallel. This structure can reduce the PAPR of branch signals and improve the power efficiency of PA. The simulation results indicate that the power efficiency will be remarkably increased.

关键词： Green Radio power amplifier signal decomposed

Multiary turbo code fitting for unitary space-time modulation and its MAP decoding algorithm

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Science china(Information Sciences) 2010年第12期53卷 2610-2619页

作者： ZHANG DaPeng 1,2,3,LU Ju 1,XU HongJi 1 & ZHANG xingYu 1 1 School of Information Science and Engineering,Shandong university,Jinan 250100,china 2 state key laboratory of integrated services networks,xidian university,xi'an 710077,china 3 Department of Avionics Engineering,First Aeronautical College of the Air Force,xinyang 464000,china School of Information Science and Engineering Shandong University Jinan China state key laboratory of integrated services networks Xidian University Xi’an China Department of Avionics Engineering First Aeronautical College of the Air Force Xinyang China

Unitary space-time modulation(USTM) fits for rapid Rayleigh flat fading channels as it can realize wireless communication when neither the transmitter nor the receiver knows the channel state information(CSI).However,an intrinsic problem is that only when the signal-to-noise ratio(SNR) is high can it give an ideal bit error rate(BER) *** existing bit-wise processing scheme of the combination of turbo code and USTM improves the BER performance and results in an unacceptable calculation complexity,storage and time delay *** this paper,we propose a multiary processing scheme and its corresponding multiary MAP decoding *** results verify that our scheme can reduce the system complexity while keep a good BER ***,we present the first analysis of the reason for the BER performance deterioration of the combination scheme at low SNR with the help of the definition of USTM.

关键词： multiple-input multiple-output unitary space-time modulation turbo code MAP decoding diversity

Spectrum Resource Management of Cognitive Radio

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ZTE Communications 2009年第2期7卷 27-31页

作者： Liu Qin (state key laboratory of integrated services networks , xidian university, xi’an 710071 , P . R . china )

As the most important technology of CR, the wireless spectrum resource management technology is the key to CR performance improvement. By introducing the concept of resource space to describe wireless spectrum resource management in the field of CR technology, a data system of wireless resource management is formed that covers wireless spectrum resource space, resource grid and available resource atlas. Besides, the corresponding lamination distributional management structure and the resource management database are constructed. The resources description system and the management structure will become the theoretical concept foundation and reference of the CR spectrum resources management technology.

关键词： As Spectrum Resource Management of Cognitive Radio IEEE Figure

SAR image despeckling based on edge detection and nonsubsampled second generation bandelets

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Journal of Systems Engineering and Electronics 2009年第3期20卷 519-526页

作者： Zhang Wenge~(1,2),Liu Fang~(1,2),Jiao Licheng~(2,3)& Gao xinbo~(2,3) 1.School of Computer Science and Technology,xidian Univ.,xi’an 710071,P.R.china 2.key Lab.of Intelligent Perception and Image Understanding of Ministry of Education of china,xi’an 710071,P.R.china 3.Inst,of Intelligent Information Processing,xidian Univ.,xi’an 710071,P.R.china School of Computer Science and Technology Xidian Univ. Xi'an 710071 P. R. China key Lab. of Intelligent Perception and Image Understanding of Ministry of Education of china Xi'an 710071 P. R. China key Lab. of Intelligent Perception and Image Understanding of Ministry of Education of china Xi'an 710071 P. R. China Inst. of Intelligent Information Processing Xidian Univ. Xi'an 710071 P. R. China

To preserve the sharp features and details of the synthetic aperture radar （SAR） image effectively when despeckling, a despeckling algorithm with edge detection in nonsubsampled second generation bandelet transform （NSBT） domain is proposed. First, the Canny operator is utilized to detect and remove edges from the SAR image. Then the NSBT which has an optimal approximation to the edges of images and a hard thresholding rule are used to approximate the details while despeckling the edge-removed image. Finally, the removed edges are added to the reconstructed image. As the edges axe detected and protected, and the NSBT is used, the proposed algorithm reaches the state-of-the-art effect which realizes both despeckling and preserving edges and details simultaneously. Experimental results show that both the subjective visual effect and the mainly objective performance indexes of the proposed algorithm outperform that of both Bayesian wavelet shrinkage with edge detection and Bayesian least square-Gaussian scale mixture （BLS-GSM）.

关键词： computer image processing synthetic aperture radar speckle edge detection nonsubsampled second generation bandelet transform Canny operator threshold shrinkage.