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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 {4., Xi’an 710071,China 3. Shandong Finance Institute, Jinan 250014. China 4. school of Mathematical sciences, Peking {4., beijing 100871, China 1. school of science Beijing University of Posts and Telecommunications 100876 Beijing China 2. State Key Laboratory of Integrated Services Network Xidian University 710071 Xi’an China 3. Shandong Finance Institute 250014 Jinan China 4. school of Mathematical sciences Peking University 100871 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

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 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)

Research on user-aware QoS based Web services composition

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The Journal of China Universities of posts and telecommunications 2009年第5期16卷 125-130页

作者： LIU Feng , LEI Zhen-ming Key Laboratory of Information Processing and Intelligent Technology, beijing university of posts and telecommunications, beijing 100876, China [a]Key Laboratory of Information Processing and Intelligent Technology beijing university of posts and telecommunications beijing 100876 China

To improve user experience of composite Web services, a user-aware quality of service （QoS） based Web services composition model is proposed. Under such model, a Web services selection method based on quantum genetic algorithm is proposed. This algorithm uses quantum bit encoding, dynamic step-length quantum gate angle adjustment, neighborhood service search and dynamic punishment strategy to expand search scope and speed up convergence. Simulation experiment shows that this algorithm is more efficient than other existing algorithms in Web services selection.

关键词： Web services composition user awareness quality of service quantum genetic algorithm

Solutions of Minimal Period for An Extended Hamiltonian System

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The Journal of China Universities of posts and telecommunications 2002年第3期9卷 23-27,37页

作者： LIU Bao-sheng (school of science, beijing university of posts and telecommunications, beijing 100876, P.R.China) school of science Beijing University of Posts and Telecommunications Beijing 100876 P.R.China

Solutions of minimal period for the Hamiltonian system =JH′(x) has been proven under the conditionas H″(x) -1 →0 as |x|→∞ and H(x) is of higher order than 2 in the neighborhood of the origin; In this paper, w... 详细信息

关键词： hamiltonian system morse index minimal period solution

Transmit-reference UWB system based on m-sequence codes

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The Journal of China Universities of posts and telecommunications 2010年第1期17卷 25-31页

作者： ZHAO Lin-li,Lü Tie-jun,QIAO Yong-wei school of Information and Communication Engineering,beijing university of posts and telecommunications,beijing 100876,China [a] school of Information Communication Engineering Beijing University of Posts telecommunications Beijing 100876 China

In this article, a novel transmit-reference （TR） signaling scheme is proposed for ultra-wideband （UWB） system, where by invoking m-sequence codes the reference and data pulses can be transmitted side by side to increase the data rate. This structure enables demodulation with a simple and practical autocorrelation receiver despite existence of severe inter-pulse interference （IPI） To evaluate detection performance of the new designs, closed-form expression for bit error probability （BRP） is theoretically derived and simulation results confirm the analytical results. In addition, the proposed scheme can be extended to M-ary systems to further improve the data rate and power efficiency.

关键词： UWB TR IPI m-sequence M-ary

Some Properties of The Solutions of Higher Analogue of The Painlevé Equation

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Acta Mathematicae Applicatae Sinica 2006年第1期22卷 59-64页

作者： Ye-zhou Li school of science,beijing university of {4. and Elecommunications,beijing 100876,China school of Aeronautical sciences and Engineering,beijing university of Aeronautics and Astronautics,beijing 100083 school of science Beijing University of Posts Elecommunications Beijing 100876 China school of Aeronautical sciences Engineering Beijing University of Aeronautics Astronautics Beijing 100083

In this paper, we investigate the value distribution properties for the solution w（z） of higher-order Painlevé equations. We prove that the Nevanlinna＇s second main inequality for w（z） is reduced to an asymptoti... 详细信息

关键词： Painlevé equation the second main inequality value distribution

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,beijing 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

QoS-guaranteed multi-relay selection and power allocation optimization in cooperative systems

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The Journal of China Universities of posts and telecommunications 2010年第6期17卷 25-31页

作者： CHEN Dan,JI Hong,LI Xi,LI Yi College of Information and Communication Engineering,beijing university of posts and telecommunications,beijing 100876,China [a] College of Information Communication Engineering Beijing University of Posts telecommunications Beijing 100876 China

This paper investigates the relay selection and power allocation problem in multi-user based cooperative networks,where intermediate relay nodes help source forward information to destination using decode-and-forward （DF） relaying protocol. Specifically,we propose a novel multi-relay nodes selection strategy taking both instantaneous channel state information （I-CSI） and residual energy into consideration,by which ＇emergence＇ diversity gain can be achieved and the imbalance of resource utilization can be overcome. Besides,using Largangian dual-primal decomposition and subgradient projection approach,an optimal power allocation algorithm at source and cooperative relay nodes is presented with the constraints of each user＇s individual quality of service （QoS） requirements and system total transmit power. Theoretical analysis and simulation results demonstrate that the proposed scheme can significantly improve energy efficiency,while guaranteeing a good balance between achievable data rate and average network lifetime with relatively low implementation complexity.

关键词： cooperative diversity relay selection resource allocation Lagrangian dual-primal decomposition subgradient projection

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, beijing 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