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Resource scheduling scheme with QoS support in two-hop relay-enhanced OFDMA systems

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The Journal of china Universities of posts and telecommunications 2010年第4期17卷 26-30页

作者： LIU Wei ,JI Hong,LI Ting school of information and Telecommunication {3.,beijing University of posts and telecommunications,beijing 100876,china [a] school of information Telecommunication engineering Beijing University of Posts telecommunications Beijing 100876 China

As the system performance is obviously improved by introducing the concept of relay into the traditional orthogonal frequency division multiple access （OFDMA） systems, resource scheduling in relay-enhanced OFDMA systems is worthy of being studied carefully. To solve the optimization problem of achieving the maximum throughput while satisfying the quality of service （QoS） and guaranteeing the fairness of users, a novel resource scheduling scheme with QoS support for the downlink of two-hop relay-enhanced OFDMA systems is proposed. The proposed scheme, which is considered both in the first time sub-slot between direct link users and relay stations, and the second time sub-slot among relay link users, takes QoS support into consideration, as well as the system throughput and the fairness for users. Simulation results show that the proposed scheme has good performance in maximizing system throughput and guaranteeing the performance in the service delay and the data loss rate.

关键词： relay OFDMA QoS resource scheduling

Error exponents for two-hop Gaussian multiple source-destination relay channels

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Science china(information Sciences) 2012年第2期55卷 348-359页

作者： DENG PanLiang1,3.LIU YuanAn1,3.XIE Gang2,3.WANG XiaoYu1,3.TANG BiHua1,3.& SUN JianFeng1,3.1school of Electronic engineering,beijing University of {3. and telecommunications,beijing 100876,china 2school of information and communication engineering,beijing University of {3. and telecommunications,beijing 100876,china 3.ey Laboratory of Universal Wireless communication,Ministry of Education,beijing 100876,china 1. school of Electronic engineering Beijing University of Posts and Telecommunications Beijing 100876 China3. Key Laboratory of Universal Wireless Communication Ministry of Education Beijing 100876 China2. School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

We investigate the two-hop multiple source-destination relay channels using the rate splitting trans-mission scheme where each source can split its message into private and public *** determine the system error probability via integrated exponent function under amplify-and-forward(AF)and decode-and-forward(DF)relay *** most significant difference between AF and DF system error probability evaluations lies in a minimized cut-set bound of transmission rate under the DF *** are many cases among transmission rate intervals for different system parameters(*** power)and it is extremely complex to derive the system error probability for the DF *** obtain a relatively simple result,which unifies various cases by a few *** results show that the system error probability decreases with the increase of the public ***,in order to draw deep insight into the reliability requirement of each source node in this network,we provide the error exponent region(EER)for different source nodes to show the trade-off of error probability among source nodes.

关键词： error exponent error exponent region rate splitting multiple source-destination relay channel

Radio resource management strategy for VoIP service in TD-HSDPA system

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The Journal of china Universities of posts and telecommunications 2009年第4期16卷 29-33页

作者： HE Da-jiang ,CUI Jie,CHANG Yong-yu,YANG Da-cheng school of communication and information {3.,beijing University of posts and telecommunications,beijing 100876,china [a]school of communication and information {3. beijing University of posts and telecommunications beijing 100876 china

In this article, the performance of a novel radio resource management （RRM） strategy for voice over IP （VoIP） service will be evaluated in low code rate （LCR） time duplex high speed downlink packet access （TD-HSDPA） system. This novel RRM strategy is studied from the aspects of scheduling algorithm and time slot assignment algorithm. As VolP is delay sensitive service, the delay based proportional fair （DBPF） scheduler is proposed in this article. Smart antenna （SA）, which is adopted in LCR TD-HSDPA, can obtain spatial information from the direction of arrival （DOA） estimation. To exploit this spatial information further, a dynamic time slot allocation （DTA） algorithm is introduced to cooperate with the DBPF scheduler. The performance of the round robin （RR）, proportional fair （PF） with the random time slot allocation （RTA） algorithm will be given to demonstrate the benefits of this novel DBPF with DTA RRM strategy. The system level simulation results prove that the performance of this novel RRM strategy is the best of all the RRM strategies.

关键词： RRM smart antenna VolP DBPF DTA HARQ AMC

Generalized quantum state sharing of the arbitrary two particles state

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2064-2068页

作者： WANG Chuan 1,2,ZHANG Yong 1,2 & JIN GuangSheng 1,2 1 school of Science,beijing University of posts and {3.,beijing 100876,china 2 Key Laboratory of Optical communication and Lightwave Technologies,beijing University of posts and {3.,beijing 100876,china 1. school of Science Beijing University of Posts and Telecommunications Beijing 100876 China2. Key Laboratory of Optical Communication and Lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 China

This paper has proposed a generalized quantum state sharing protocol of an arbitrary two-particle state using non-maximally GHZ states and generalized Bell state *** sender Alice performs two-particle generalized Bell state measurements on her two particles in the state sharing process and the controller takes measurements on his particles and transfers the quantum information to the receiver with entanglement swapping by the cooperation of the other *** is found that the use of nonmaximally entangled state in quantum state sharing has enabled the secure sharing of the quantum state.

关键词： quantum state sharing quantum entanglement arbitrary two particles state

Performance analysis of rate-adaptive cooperative MAC based on wireless local area networks

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The Journal of china Universities of posts and telecommunications 2009年第5期16卷 78-85页

作者： ZHANG Yang , XU Hong-kun, CHANG Yong-yu, YANG Da-cheng, WANG Ya-feng school of information and communication {3., beijing University of posts and telecommunications, beijing 100876, china [a]school of information and communication {3. beijing University of posts and telecommunications beijing 100876 china

Bi-dimensional Markov chain model based on cooperative medium access control （MAC） of wireless local area networks （WLAN） is considered to reflect system performance accurately. Two basic factors that affect the analysis results are station retry limits and non-saturated transmit probability. A uniform solution considering both factors is proposed. To prove the theoretical analysis, a cooperative MAC （CoopMAC） topology is established and the simulation model is enhanced by changing the cooperative table to the nodes＇ memory with more information added. Meanwhile, the three-way handshake scheme is modified and a handshake threshold is set based on the packet size. Simulation results show the performance analytical model is accurate, and the rate-adaptive cooperative MAC protocol significantly improves the network performance in terms of non-saturated system throughput and delay.

关键词： performance analysis cooperative MAC bi-dimensional Markov Chain non-saturated transmit station retry limit

Asymptotic performance of amplify-and-forward MIMO relaying with transmit antenna selection

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Science china(information Sciences) 2010年第12期53卷 2631-2641页

作者： CAO Lei ,YANG DaCheng,YANG HongWen,FENG Chao & ZHANG Xin school of information and communication,{3. University of posts and telecommunications,beijing 100876,china 1. school of information and communication Beijing University of Posts and Telecommunications Beijing 100876 China

This paper proposes two schemes,TAS-SD&RD and TAS-SR&RD,in which transmit antenna selection(TAS) strategies are combined with amplify-and-forward(AF) protocol in MIMO relaying scenario considering the destination has only limited channel state information(CSI) of the source-to-relay channel,and analyzes asymptotic performance of the two *** source,destination,and relay are equipped with multiple antennas,denoted by N S,N D,and N R,***,the paper derives the asymptotic outage probability and symbol error rate(SER) of the proposed schemes in the cooperative AF MIMO relaying *** analyses in high SNR regime lead to the conclusion that TAS-SD&RD and TAS-SR&RD can achieve full diversity order,N S N D + N R min{N S,N D },in some antenna configurations of the cooperative *** results that confirm our analyses are also presented in the paper.

关键词： cooperative amplify-and-forward(AF) multiple-input multiple-output(MIMO) relaying transmit antenna selection(TAS)

Direct-sequence codes based blind synchronization algorithm for UWB systems

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The Journal of china Universities of posts and telecommunications 2009年第3期16卷 45-51页

作者： QIAO Yong-wei,L Tie-jun,REN Zhi-yuan school of information engineering,{3. University of posts and telecommunications,beijing 100876,china [a]school of information engineering beijing University of posts and telecommunications beijing 100876 china

A new blind （non-data-aided） synchronization algorithm based on direct-sequence （DS） codes is proposed for ultra-wideband （UWB） systems. The proposed approach fully exploits prior knowledge of DS codes and bypasses channel estimation. The real-time acquisition is achieved using integrating-and-dumping （I＆D） operation and DS codes matching filter. Because of pseudo randomicity and periodicity of DS codes, both the speed and the accuracy of synchronization are improved significantly. A lower bound on the acquisition probability of the proposed approach is also derived. Simulations confirm performance improvement of the proposed algorithm relative to existing alternatives in terms of acquisition probability, normalized mean square error （NMSE）, and bit error rate （BER）.

关键词： UWB systems synchronization DS codes

Reverse reconciliation for continuous variable quantum key distribution

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Science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 100-105页

作者： LU ZhiXin 1,2 , YU Li 1,2 , LI Kang 1,2 , LIU BingCan 1,2,3., LIN JianGui 1,2 , JIAO RongZhen 1,2 & YANG BoJun 1,21 school of Science, beijing University of posts and {3., beijing 100876, china 2 Key Laboratory of information Photonics and Optical communication, Ministry of Education, beijing University of posts and {3., beijing 100876, china 3.Department of Fundamental Courses, Academy of Armored Force {13., beijing 100072, china 1. school of Science Beijing University of Posts and Telecommunications Beijing 100876 China2. Key Laboratory of Information Photonics and Optical Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China3. Department of Fundamental Courses Academy of Armored Force Engineering Beijing 100072 China

An efficient and practical post-processing technique based on reverse reconciliation for continuous variable quantum key distribution is proposed and simulated with low-density parity check (LDPC) codes. MultiLevel Coding/ MultiStage Decoding, which fully utilizes optimization technique such as vector quantization and iterative decoding and the optimal channel coding most close to the Shannon limit, was used to realize efficient reverse reconciliation algorithm. Simulation results showed that the proposed method can improve the secure key distribution rate to 2.2 kb/s and the coding efficiency to 0.89 over 20 km in single-mode optical fiber. Moreover, there still is room for much improvement.

关键词： quantum communication key distribution reverses reconciliation low-density parity check codes

Threshold quantum secure direct communication without entanglement

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Science china(Physics,Mechanics & Astronomy) 2008年第2期51卷 176-183页

作者： YANG YuGuang1,3.& WEN QiaoYan2 1 College of Computer Science and Technology, beijing University of Technology, beijing 100022, china 2 {3. of Science, beijing University of posts and telecommunications, beijing 100876, china 3.State Key Laboratory of information Security (Graduate {3. of Chinese Academy of Sciences), beijing 100049, china 1. College of Computer Science and Technology Beijing University of Technology Beijing 100022 China 3. State Key Laboratory of information Security (Graduate school of Chinese Academy of Sciences) Beijing 100049 China 2. school of Science Beijing University of Posts and Telecommunications Beijing 100876 China

For the first time, a threshold quantum secure direct communication (TQSDC) scheme is presented. Similar to the classical Shamir's secret sharing scheme, the sender makes n shares, S1, …, Sn of secret key K and each receiver keeps a share secretly. If the sender wants to send a secret message M to the receivers, he en-codes the information of K and M on a single photon sequence and sends it to one of the receivers. According to the secret shares, the t receivers sequentially per-form the corresponding unitary operations on the single photon sequence and ob-tain the secret message M. The shared shares may be reusable if it can be judged that there is no eavesdropper in line. We discuss that our protocol is feasible with current technology.

关键词： quantum secure direct communication threshold secure direct communication quantum secret sharing