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Data-aided synchronization algorithm dispensing with searching procedures for UWB communications

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Science china(information Sciences) 2012年第4期55卷 778-788页

作者： REN ZhiYuan 1,JIANG Ting1,ZHONG Yi 2 & ZHAO ChengLin 1 1 Key Laboratory of Universal Wireless communications,Ministry of Education of china Wireless Network Laboratory,beijing university of {4. and Telecommunications,beijing 100876,china 2 school of information engineering,North china university of Technology,beijing 10004.,china 1. Key Laboratory of Universal Wireless communications Ministry of Education of China Wireless Network Laboratory Beijing University of Posts and Telecommunications Beijing 100876 China2. School of Information Engineering North China University of Technology Beijing 100041 China

Rapid and accurate synchronization constitutes a major challenge in deploying Ultra-Wideband impulse radio (UWB-IR) for indoor wireless *** paper develops a data-aided (DA) synchro-nization algorithm dispensing with searching procedures for UWB-IR *** adopting a stream of alternating orthogonal pulses,frame-level synchronization can be achieved without channel ***-out utilizing any searching procedure,the timing offset estimator is obtained in a closed *** exhaustive search can be avoided,both computational complexity and synchronization time are *** and comparisons are provided to illustrate the advantages of our design over the alternatives.

关键词： Ultra-Wideband impulse radio synchronization dispensing with searching procedures searching space data-aided estimation

Network parameters awareness for routing discovery in autonomic optical Internet

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The Journal of china Universities of posts and Telecommunications 2009年第2期16卷 84-88,128页

作者： JIN Jin WANG Hong-xiang JI Yue-feng Key Laboratory of Optical communication and Lightwave Technologies,beijing university of posts and Telecommunications,beijing 100876,china [a]Key Laboratory of Optical communication and Lightwave Technologies beijing university of posts and Telecommunications beijing 100876 china

The article proposes a network parameter-awareness （NPA） method and applies it to routing discovery algorithms in autonomic optical Internet. This NPA method can perceive the main parameters of the network, such as delay, jitter and traffic, which can represent the current situation of the network. And these parameters enable network to determine the appropriate nodes for routing discovery. The simulation results of evaluating performance of a network with NPA method and its routing applications show that the method and its applications in routing improve the performance of the network significantly with quality of service （QoS） guaranteed.

关键词： NPA autonomic optical Internet self-aware muting QoS

ALGEBRAICALLY CONSTRUCTED COSTAS ARRAYS WITH SMALL NUMBER OF CROSS-COINCIDENCES

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Systems Science and Mathematical Sciences 2000年第3期13卷 242-249页

作者： YANG Yixian(information Security Center, Depertment of information engineering, beijing {4. of posts and Telecommunication, beijing 100876, china) 北京 100876

Eight families of Costas arrays with ideal cross-coincidence are algebraically constructed under the assumptin that the vertical shifts are appropriately *** Costas arrays are useful for designing multiple Costas wavforms with small crossambiguities, if the potential Doppler shifts are restricted to a small portion of the wavform bandwidth.

关键词： Costas arrays signal design coding optical orthogonal codes

Quantum threshold group signature

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Science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1505-1514页

作者： YANG YuGuang1,2,3 & WEN QiaoYan4.1 College of Computer Science and Technology, beijing university of Technology, beijing 100124. china 2 State Key Laboratory of Integrated Services Network, Xidian university, Xi’an 710071, china 3 State Key Laboratory of information Security (Graduate university of Chinese Academy of Sciences), beijing 10004., china 4.State Key Laboratory of Networking and Switching Technology, beijing university of posts and Tele-communications, {14., china College of Computer Science and Technology Beijing University of Technology Beijing 100124 China State Key Laboratory of Integrated Services Network Xidian University Xi’an 710071 China State Key Laboratory of information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

In most situations, the signer is generally a single person. However, when the message is written on behalf of an organization, a valid message may require the approval or consent of several persons. Threshold signature is a solution to this problem. Generally speaking, as an authority which can be trusted by all members does not exist, a threshold signature scheme without a trusted party appears more attractive. Following some ideas of the classical Shamir’s threshold signature scheme, a quantum threshold group signature one is proposed. In the proposed scheme, only t or more of n persons in the group can generate the group signature and any t-1 or fewer ones cannot do that. In the verification phase, any t or more of n signature receivers can verify the message and any t-1 or fewer receivers cannot verify the validity of the signature.

关键词： threshold quantum signature trusted party quantum cryptography

Threshold proxy quantum signature scheme with threshold shared verification

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Science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 1079-1088页

作者： YANG YuGuang1,3,4.& WEN QiaoYan2 1 College of Computer Science and Technology,beijing university of Technology,beijing 100124.china 2 State Key Laboratory of Networking and Switching Technology,beijing university of posts and Tele-communications,beijing 100876,china 3 State Key Laboratory of Integrated Services Network,Xidian university,Xi’an 710071,china 4.State Key Laboratory of information Security(Graduate university of Chinese Academy of Sciences) ,beijing 10004.,china 1. College of Computer Science and Technology Beijing University of Technology Beijing 100124 China 3. State Key Laboratory of Integrated Services Network Xidian University Xi’an 710071 China 4. State Key Laboratory of information Security (Graduate university of Chinese Academy of Sciences) Beijing 100049 China 2. State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

A threshold proxy quantum signature scheme with threshold shared verification is proposed. An original signer could authorize a group as its proxy signers. Then only t or more of n persons in the proxy group can generate the proxy signature on behalf of the original signer and any t-1 or fewer ones cannot do that. When the proxy signature needs to be verified,any t or more of n persons belonging to the verification group can verify the message and any t-1 or fewer ones cannot verify the validity of the proxy signature.

关键词： quantum signature threshold proxy quantum group signature threshold shared verification

Threshold quantum secret sharing between multi-party and multi-party

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Science china(Physics,Mechanics & Astronomy) 2008年第9期51卷 1308-1315页

作者： YANG YuGuang1,2,3 & WEN QiaoYan4.1 College of Computer Science and Technology,beijing university of Technology,beijing 100124.china 2 State Key Laboratory of Integrated Services Network,Xidian university,Xi’an 710071,china 3 State Key Laboratory of information Security (Graduate university of Chinese Academy of Sciences),beijing 10004.,china 4.State Key Laboratory of Networking and Switching Technology,beijing university of posts and Tele-communications,{14.,china College of Computer Science and Technology Beijing University of Technology Beijing 100124 China State Key Laboratory of Integrated Services Network Xidian University Xi’an 710071 China State Key Laboratory of information Security (Graduate university of Chinese Academy of Sciences) Beijing 100049 China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

A threshold quantum secret sharing (TQSS) scheme between multi-party and multi-party was proposed using a sequence of single photons,which is useful and efficient when the parties of communication are not all present. We described the process of this TQSS scheme and discussed its security. It was shown that entan-glement is not necessary for quantum secret sharing. Moreover,the theoretic effi-ciency was improved to approach 100% as almost all the instances can be used for generating the private key,and each photon can carry one bit of information. This protocol is feasible with the present-day technique.

关键词： threshold quantum secret sharing quantum cryptography single photon multi-party and multi-party

Inferring playback rate and rate resets of P2P video streaming transmissions by piecewise line envelope approximation

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The Journal of china Universities of posts and Telecommunications 2009年第2期16卷 58-62,79页

作者： LI Chun-xi CHEN Chang-jia school of Electronics and information engineering,beijing Jiaotong {4.,beijing 10004.,china [a]school of Electronics and information engineering beijing Jiaotong university beijing 10004. china

Conventionally, P2P video is regarded as CBR traffic. However, our measurements have shown that the rate reset cannot be neglected in a practical IPTV system because each rate reset often leads to performance degradation. Thus, addressing the problem of inferring playback rate and rate reset in a P2P video system is significant. In this article, an algorithm termed piecewise linear envelope approximation （PLEA） is proposed, in which a follow-up time is introduced to smooth rate fluctuations in a small time scale and to adapt rate jumps in a large time scale automatically. With the PLEA algorithm, discontinuity introduced by blind segmentations adopted by current methods is avoided. Furthermore, unlike existing algorithms in which both segmentation and combinations are performed in multiple runs, only a single computation path is involved in the PLEA algorithm. This makes PLEA algorithm amenable to implementation of low complexity by either software or hardware. Both theoretical analysis and experiment based on measured data show that the PLEA outperforms existing algorithms based on segmentation.

关键词： P2P video playback rate rate reset convex hull linear program

MMSE relay precoding schemes based on quantization error compensation for multi-relay system

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Science china(information Sciences) 2010年第12期53卷 2548-2556页

作者： LI Ting 1,2 & YANG LuXi 2 1 College of communication and information engineering,Nanjing university of {4. and Telecommunications,Nanjing 210003,china 2 school of information Science and engineering,Southeast university,Nanjing 210096,china 1. College of communication and information engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China2. School of Information Science and Engineering Southeast University Nanjing 210096 China

In order to deal with the performance degradation resulting from the quantization error,this paper introduces the statistics of Grassmannian codebook's quantization error into relay precoding design for multirelay *** on the two-step MMSE optimization algorithm for relay precoding and receiver equalizing with full feedback under QoS requirements,we first propose a limited feedback two-step MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation,and then we propose a limited feedback joint MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation subject to a global power constraint at the output of *** results show that the proposed joint MMSE optimization scheme with quantization error compensation has a much lower bit-error rate than the two-step MMSE optimization scheme with quantization error compensation and the joint MMSE optimization scheme without quantization error compensation.

关键词： multi-relay precoding limited feedback minimum mean square error

Synchronization of Digital Chaos in Secure communication Systems

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Journal of university of Science and Technology beijing 2001年第4期8卷 299-305页

作者： Geng Zhao, Deling Zheng, ShaojunHuang 1)College of Electric Science and Technology beijing. beijing 100070, china 2)information {4. school, university of Science and Technology beijing. beijing 100083, china Coll Elect Sci & Technol beijing Beijing 100070 Peoples R China Univ Sci & Technol beijing Informat Engn Sch Beijing 100083 Peoples R China

The theories of synchronization based on secure communications using digital chaos are presented. A new synchronous method-cycles-interval Pulse drive is developed and realized. Experimental results show it is available, and in order to reduce synchronous noise, a method using model references solves the ratio of signal power to noise power, so the secure communication system can be realized.

关键词： digital chaotic synchronization cycles-interval pulses drive synchronous noise model reference