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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 100049,china 4 state key laboratory of networking and Switching Technology,Beijing university of Posts and Tele-communications,Beijing 100876,china College of Computer Science and Technology Beijing University of Technology Beijing China state key laboratory of integrated services network Xidian University Xi’an China state key laboratory of Information Security (Graduate university of Chinese Academy of Sciences) Beijing China state key laboratory of networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 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

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

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

A novel distortion elimination method of power amplifier in wideband OFDM system

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Science china(Information Sciences) 2012年第2期55卷 396-406页

作者： REN ZhiYuan & ZHANG HaiLin state key laboratory of integrated services network,xidian university,xi’an 710071,china state key laboratory of integrated services network Xidian University Xi’an China

The nonlinear,memory and saturate distortion caused by power amplifier lead to low BER per-formance and low power efficiency in wideband OFDM *** solve the related problems,a novel power amplifier based on combined amplification with multi power amplifiers is proposed in this *** addition,a novel simplified filter look-up table predistorter is *** novel predistorter connects to a memoryless predistorter subsystem with an adaptive filter subsystem in cascade,and can eliminate the nonlinear memory distortion *** simulation results indicate that the power efficiency and BER performance will be improved by using the novel amplifier structure together with the novel predistorter.

关键词： wideband OFDM dynamic range extended memory predistorter

A class of quasi-cyclic LDPC codes from B2 （mod m） sequences

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Science china(Information Sciences) 2011年第8期54卷 1645-1653页

作者： ZHANG GuoHua & WANG xinMei state key laboratory of integrated Service network,xidian university,xi’an 710071,china state key laboratory of integrated Service network Xidian University Xi’an China

A new class of binary low-density parity-check (LDPC) codes is proposed based on B 2 (mod m) sequences. The parity-check matrix of such a code has a column weight of three and a row weight of an arbitrary integer,and a quasi-cyclic *** parity-check matrix also has a girth at least 8,and corresponds to a code with minimal distance at least *** m is prime,an 8-cycles reduction method is presented to completely avoid the two types of 8-cycles within the total four types existed in the Tanner *** results show that,for a prime integer m,the new LDPC code outperforms the random (quasi-) regular counterpart generated by the PEG ***,a heuristic algorithm based on a strategy called neighboring extension search is presented to search for the B 2 (mod m) sequences whose lengths approach or meet the upper bound.

关键词： channel coding LDPC code B2 (mod m) sequencegirth

A network coding based hybrid ARQ algorithm for wireless video broadcast

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Science china(Information Sciences) 2011年第6期54卷 1327-1332页

作者： LU Ji , WU ChengKe, xiAO Song & DU JianChao state key laboratory of integrated services network, xidian university, xi’an 710071, china state key laboratory of integrated services network Xidian University Xi’an China

This paper proposes a network coding (NC) based hybrid ARQ (HARQ) algorithm for video broad- cast over wireless networks. The sender applies NC technique to combine the lost packets of different terminals, so that multiple terminals can recover their lost packets via per transmission from the sender. The proposed algorithm combines the advantage of FEC scheme and NC based ARQ scheme so as to maximize not only wireless throughput but also video quality for broadcast communication. Simulation results show that our algorithm significantly improves both wireless throughput efficiency and video quality, compared with ARQ and HARQ schemes.

关键词： wireless networks network coding hybrid ARQ video transmission

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 100049,china College of Computer Science and Technology Beijing University of Technology Beijing China state key laboratory of integrated services network Xidian University Xi’an China state key laboratory of Information Security (Graduate university of Chinese Academy of Sciences) Beijing China state key laboratory of networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 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

Space-time cooperative diversity scheme using full feedback

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The Journal of china Universities of Posts and Telecommunications 2009年第3期16卷 8-13页

作者： SUN De-chun,YI Ke-chu,LI xiao-hui state key laboratory of integrated Service networks,xidian university,xi’an 710071,china state key laboratory of integrated Service networks Xidian University Xi'an 710071 china

This article proposes a new space-time cooperative diversity scheme called full feedback-based cooperative diversity scheme （FFBCD）. In contrast to the conventional adaptive space-time cooperative diversity schemes that utilize the feedback from only the destination node, the new scheme utilizes the feedback from both the destination node and the cooperation node. With the feedback from the destination node, the occasional successful reception of the destination node in the information distribution stage can be detected, thus avoiding unnecessary retransmissions in the information delivery stage. The feedback from the cooperation node indicates the receiving state of the cooperation node in the information distribution stage, and the source node and the cooperation node will not perform cooperative retransmission during the information delivery stage unless the cooperation node is received successfully in the information distribution stage. In this way the new scheme can reduce the number of transmission attempt and improve the channel utilization. The expressions of the average number of transmission attempt are given. Numerical approximations and simulation results both show that the new scheme performs better than the non-cooperative scheme and the conventional adaptive space-time cooperative diversity scheme.

关键词： space-time cooperative diversity simple feedback adaptive cooperative diversity transmission attempt

Exact thresholds for low-density parity-check codes over the binary erasure channel

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Progress in Natural Science:Materials International 2009年第7期19卷 897-900页

作者： Jianjun Mu a, xiaopeng Jiao a, xinmei Wangb a School of Computer Science and Technology, xidian university, xi’an 710071, china b state key laboratory of integrated Service networks, xidian university, xi’an 710071, china School of Computer Science and Technology Xidian University Xi’an 710071 China state key laboratory of integrated Service networks Xidian University Xi’an 710071 China

A simple method for determining the threshold of irregular LDPC codes over the binary erasure channel (BEC) under message-passing decoding is proposed. An exact formula for calculating the threshold of irregular LDPC codes over the BEC is proved. This generalizes the known result on the threshold of regular LDPC codes to irregular LDPC codes. Moreover, our new method can avoid the computation of the inverse of the degree distribution function for irregular LDPC codes. Numerical results demonstrate the correctness of our proposed method.

关键词： Binary erasure channel (BEC) LDPC codes Threshold