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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 engineering,{4. university of posts and Telecommunications,beijing 100876,china [a]school of communication and information engineering 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 Tele{4.s,beijing 100876,china 2 Key Laboratory of Optical {4. and Lightwave Technologies,beijing university of posts and Tele{4.s,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

Robust multiuser MIMO scheduling algorithms with imperfect CSI

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Science china(information Sciences) 2012年第4期55卷 815-826页

作者： MAO JunLing 1,3,GAO JinChun 1,3,LIU YuanAn 1,3,XIE Gang 2,3 & ZHANG Jian 1,3 1 school of Electronic engineering,beijing university of {4. and Telecommunications,beijing 100876,china 2 school of information and communication engineering,beijing university of {4. and Telecommunications,beijing 100876,china 3 Key Lab of Universal Wireless communications,Ministry of Education,beijing university of {4. and Telecommunications,beijing 100876,china 1. school of Electronic engineering Beijing University of Posts and Telecommunications Beijing 100876 China3. Key Lab of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China2. School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Robust multiuser multiple-input-multiple-output (MIMO) scheduling algorithms are proposed in this *** imperfect channel state information (CSI),traditional scheduling algorithms for the multiuser MIMO system based on the zero forcing precoding scheme will lose some performance due to the multi-user interference (MUI).In order to improve the system average throughput,we study the robust multiuser MIMO scheduling problem with imperfect *** the average capacity formula,we derive a robust factor which can transform the robust multiuser MIMO scheduling problem into the traditional one,thus most existing non-robust scheduling algorithms can be robust if this factor is *** results show that compared with the traditional algorithms,the proposed robust algorithms can improve the system average throughput significantly under the CSI error environment.

关键词： multiuser MIMO (MU-MIMO) scheduling robust imperfect CSI

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 engineering, {4. university of posts and Telecommunications, beijing 100876, china [a]school of information and communication engineering 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

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 {4. and Telecommunications,beijing 100876,china 2school of information and communication engineering,beijing university of {4. and Telecommunications,beijing 100876,china 3Key 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

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,beijing {4. 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,beijing {4. 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

An efficient quantum secret sharing protocol with orthogonal product states

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Science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 331-338页

作者： YANG YuGuang1,2, WEN QiaoYan3 & ZHU FuChen4.1 school of Computer, beijing university of Technology, beijing 100022, {4. 2 State Key Laboratory of information Security, Graduate university of Chinese Academy of Sciences, beijing 100022, {4. 3 school of Science, beijing university of posts and Telecommunications, {14., {4. 4.National Key Laboratory for Modern communications, Chengdu 61004., {4. 1. school of Computer Beijing University of Technology Beijing 100022 China 2. State Key Laboratory of information Security Graduate University of Chinese Academy of Sciences Beijing 100022 China 3. school of Science Beijing University of Posts and Telecommunications Beijing 100876 China 4. National Key Laboratory for Modern communications Chengdu 610041 China

An efficient quantum secret sharing protocol with orthogonal product states in the 33 Hilbert space is presented. The particles in the orthogonal product states form two particle sequences. One sequence is sent to Bob and the other is sent to Charlie after rearranging the particle orders. With the help of Alice, Bob and Charlie make the corresponding local measurement to obtain the information of the or- thogonal product states prepared. This protocol has many distinct features such as great capacity and high efficiency.

关键词： quantum secret sharing orthogonal product state orthogonal measurement

Resource allocation based on genetic algorithm for multi-hop OFDM system with non-regenerative relaying

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The Journal of china Universities of posts and Telecommunications 2009年第5期16卷 25-32页

作者： SHI Jie , XU Wen-jun, HE Zhi-qiang, NIU Kai, WU Wei-ling school of information and Telecommunication engineering, {4. university of posts and Telecommunications, beijing 100876, china [a]school of information and Telecommunication engineering beijing university of posts and Telecommunications beijing 100876 china

This article investigates resource allocation in multi-hop orthogonal frequency division multiplexing （OFDM） system with amplifying-and-forwarding relaying to maximize the end-to-end capacity, Most existing methods for multi-hop system focus on power allocation or subcarrier selection separately, but joint resource allocation is rarely considered due to the absence of effective interaction schemes. In this work, a novel joint resource allocation methodology is proposed based on Partheno genetic algorithm （PGA）, which produces excellent subcarrier allocation set （referred to as individual in PGA） with higher capacity by evolution operator generation by generation. In addition, an adaptive power allocation is also designed to evaluate the fitness of PGA and further enhance the system capacity. Both theoretical analysis and simulated results show the effectiveness of the proposed joint strategy. It outperforms the traditional method by as much as 4.% capacity improvement for 3-hop relaying system when system power is high, and obtains much more capacity enhancement percent under conditions of low system power.

关键词： multi-hop OFDM system non-regenerative relaying genetic algorithm power allocation subcarrier selection resource allocation