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Coexistence of broadband power line communication systems

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The Journal of china Universities of posts and telecommunications 2009年第4期16卷 125-128页

作者： YANG Biao ,L Ying-hua,ZHANG Hong-xin school of Electronic Engineering,beijing university of posts and telecommunications,beijing 100876,china school of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Recent progress in home networks enhances the application of broadband power line communication （BPL） since it does not require any installation of new communication lines or outlets. However, high-density distribution of BPL devices may bring down the access quality. Besides, the electromagnetic field radiating from the power line may cause interference with other radio systems. Thus, the objective of this study is to investigate the impact of cumulative interference in BPL systems, especially focused on indoor environment. A 2-D model describing the BPL transmission activity is proposed. Based on transmission characteristics of the main networks, it takes into account the coexistence effect of the BPL devices. The maximum acceptable density of BPL devices and the radiation field are finally determined.

关键词： BPL coexistence effect radiating electromagnetic field

Lifetime maximization of cooperative networks with mean channel gain information

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The Journal of china Universities of posts and telecommunications 2009年第4期16卷 98-103页

作者： YANG Chang-qing,WANG Wen-bo,ZHAO Shuang,PENG Mu-gen school of Information and Communication Engineering,beijing university of posts and telecommunications,beijing 100876,china school of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

A simple but effective relay-selection and power-allocation scheme is proposed to maximize the lifetime of decode-and-forward （DF） cooperative networks under the constraint that only the mean channel gain information is available at the transmitters. The new scheme takes both channel state information （CSI） and residual energy information （REI） into consideration. To evaluate the performance of the proposed scheme, three typical relay-selection and power-allocation schemes, i.e., maximum residual energy （MRE）, minimum transmit power （MTP） and equal transmit power （ETP） are considered. Simulation results show that the proposed scheme outperforms the MRE and the MTP in lifetime duration and outage probability, while needing much less signal overhead compared with the ETP.

关键词： cooperative commtmication lifetime relay selection power allocation Rayleigh fading

Valiant load-balancing and regionalized routing scheme

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The Journal of china Universities of posts and telecommunications 2010年第3期17卷 78-84页

作者： YANG Fan , WANG Zhen-kai, CHEN Jian-ya, LIU Yun-jie school of Information and Communication Engineering, beijing university of posts and telecommunications, beijing 100876, china school of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876

Valiant load-balancing （VLB） routing scheme has drawbacks of logical full mesh, intermediate nodes （networks） and single application of topology. To address these, the authors propose a novel routing scheme called regionalized VLB （R-VLB）. Based on ideas of VLB and regionalizing, R-VLB divides the nodes of backbone network into several regions whose topological structure is logical full mesh, and combines shortest-path routing scheme and VLB routing scheme. R-VLB also achieves logical local interconnection, non-central nodes （networks） and a wide range of application of topology. The relevant theoretical analysis and simulation results show that R-VLB achieve good throughput and failure performance close to that of VLB, and it even has better delay performance. R-VLB provides an idea for the application of VLB routing scheme.

关键词： routing scheme VLB topology backbone network

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 school of Information and Communication Beijing University of Posts and Telecommunications Beijing 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)

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 school of Information and Communication Engineering Beijing University of Posts and 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

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

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 College of Information and Communication Engineering Beijing University of Posts and 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

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 posts 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 and Elecommunications Beijing 100876 China school of Aeronautical sciences and Engineering Beijing University of Aeronautics and 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

Theorems for Testing Local Activity of CNN and Application to Cardiac Purkinje Equations

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 139-146页

作者： Lequan Min(Applied science school, university of science and Technology beijing, beijing 100083, china) Applied science school University of Science and Technology Beijing Beijing 100083 China

The theorems for testing the local in one-port cellular neural/inear network (CNN) cells with four local state variables are presented. Using the theorems computes the bifurcation diagrams of the cardiac Purkinje fiber (CPE) equations Which describethe long-lasting action and pace-maker potentials of the Purkinje fiber of the heart. The computer simulation shows that periodic trajectories or convergent trajectories of the CPF Equations can be foun if the cormsponing cell Parameters are located in a positive domainbut nearby edge of chaos. In particular a heart with approximate normal frequency of heartbeat but non-normal electrocardiogram maysuddenly stop by slightly perturbing the parameters of the corresponding CPF Equations when the Paramders are located nearby the edge of chaos in the bifurcation diagrams. This research seems to interpret reasonbly the phenomena that patients with cardiac diseases might suddenly die without warning.

关键词： cellular neural network local activity cardiac Purkinje fiber heartbeat