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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,{2., 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 {2. 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

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,{2. university of posts and Elecommunications,{2. 100876,China school of Aeronautical sciences and Engineering,{2. university of Aeronautics and Astronautics,{2. 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

Practical conditions of signal space alignment for generalized MIMO Y channel

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science China(Information sciences) 2012年第10期55卷 2171-2182页

作者： SHE JiaJu 1,2.CHEN ShanZhi 1,2.HU Bo 1,WANG YingMin 2.& SU Xin 2.1 State Key Laboratory of Networking and Switching Technology,beijing university of {2. and telecommunications,beijing 100876,China 2.State Key Laboratory of Wireless Mobile Communications,China Academy of telecommunications Technology,beijing 100191,China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China State Key Laboratory of Wireless Mobile Communications China Academy of Telecommunications Technology Beijing China

This paper proposes a generalization for applications of signal space alignment(SSA) in a generalized multiple input multiple output(MIMO) Y channel with K(K 2. nodes and an intermediate *** on that generalization,a method is introduced to determine the practical conditions for *** first study the generalized MIMO Y channel model with general signal demands;then,the degrees of freedom(DoF) achieved are given and are proved using *** SSA could decrease the number of antennas at the relay,it places new restrictions on the numbers of antennas at the *** then introduce a method to compare the models with and without SSA network coding(SSA-NC),mainly from the perspective of the total number of antennas *** results show that if each node must be able to exchange signals with all others,the model with SSA will definitely use more antennas to supply the same DoF,when K > *** it is not necessary for every node to exchange signals with all others,the comparison can still be made by using the method introduced *** a result,the conditions under which SSA-NC is needed are presented.

关键词： Signal space alignment MIMO Y channel degrees of freedom number of antennas

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 {2. of posts and telecommunications,beijing 100876,China 2.0} of Information and Communication Engineering,beijing {2. of posts and telecommunications,beijing 100876,China 3Key Laboratory of Universal Wireless Communication,Ministry of Education,beijing 100876,China school of Electronic Engineering Beijing University of Posts and Telecommunications Beijing China Key Laboratory of Universal Wireless Communication Ministry of Education Beijing China school of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 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 Engineering,beijing {2. of posts and telecommunications,beijing 100876,China 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 {2. 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

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转辙机动作杆中光纤应力传感器的研究

铁道学报 2004年第6期26卷 120-122页

作者：孙强周虚北京交通大学电子信息工程学院北京100044 北京邮电大学电信工程学院北京100876

研究了非对称刻蚀光纤应力传感器的基本原理,将其应用在转辙机中,为转辙机动作杆应力的检测提供了一种新的测试方法。

关键词：光纤传感器转辙机动作杆应力

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,{2., China 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 40% 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