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2015 4th International Conference on Mechatronics,Materials,Chemistry and Computer Engineering(ICMMCCE 2015)

作者： Hongyan Cui Chenhang Ma Wei Lai Lili Zheng Yunjie Liu State Key Lab.of Networking and Switching Technology Beijing Key Lab.of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

The services carried by the Internet have undergone tremendous change over the past decades, along with the emergence of multimedia services and cloud computing, etc. However, there is little change in the framework of network designed primarily for reliable end-to-end communication, which is not suitable for these new services, resulting in poor performance of services and inefficient utilization of network resource. In this paper, we propose a network resource allocation scheme base on SDN(Software Defined network) an emerging network paradigm, to provide Quality of Service(Qo S) support for various services while balance the link load in the network avoiding congestion and idleness. And we demonstrate its performance via experiments under our SDN test bed.

关键词： SDN network Resource Allocation Quality of Service

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A novel broadband model for MIMO vehicle-to-vehicle fading channel

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Journal of Computational Information systems 2014年第2期10卷 573-580页

作者： Zhao, Ruojun Xu, Chunxiu Zhao, Min Jia, Guiyuan Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing 100876 China

In this paper, a new broadband multiple-input multiple-output (MIMO) Rayleigh fading channel is proposed for vehicle-to-vehicle (V2V) communication system. Considering the scattering environment, we first propose a novel model, called Double-layer model. It utilizes bilayer structure to describe the remote scatterers and the random distributed local scatterers. The exact relationship between the angleof- arrival (AOA) and the angle-of-departure (AOD) based on this model can be obtained. Meanwhile, the 3-D space-time cross correlation function (CCF) is studied under the non-isotropic scattering scenario utilizing the von Mises distribution. Finally, some numerical results are presented concerning the CCF. Our research work offers a more realistic propagation environment for the employment of the MIMO techniques in future V2V system. Copyright © 2014 Binary Information Press.

关键词： Fading channels

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Mining Users’ Mobility Patterns Based On Apriori

Mining Users’ Mobility Patterns Based On Apriori

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2015 4th International Conference on Mechatronics,Materials,Chemistry and Computer Engineering(ICMMCCE 2015)

作者： Hongyan Cui Xiaolong Yin State Key Lab.of Networking and Switching Technology Beijing Key Lab.of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

Mobility pattern of users is decided by people themselves. However, in the daily life, mobile users often repeat regular routes in certain periods. To effectively mine the mobile rules of users and allocate the resource among mobile telecommunication operators and Internet Service Providers（ISP）, grasping the models of human mobility can enable effective network planning and advertisement recommending. In this paper, we employ Apriori algorithm method to mine mobile users’ movement model. The algorithm proposed is based on mining the mobility patterns of users, forming mobility rules from these patterns, and finally predicting a mobile user’s next movement by using the mobility rules. The user mobility patterns are mined from the history of mobile user trajectories. In addition to the analysis of individual mobile behavior, it is possible to mine population movement regularity from a large number of user mobile patterns. By studying the group characteristics the place that a large number of users accessed can be found. Operators can optimize the setting of the base station according to the density of users to meet the needs of mobile users.

关键词： Mobility patterns Apriori Algorithm Trajectory prediction User behaviour analysis

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Design of in-network caching scheme in CCN based on grey relational analysis

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The Journal of China Universities of Posts and Telecommunications 2014年第2期21卷 1-8页

作者： CUI Xian-dong HUANG Tao LIU Jiang LI Li CHEN Jian-ya LIU Yun-jie State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Future Network Industry Innovation Center of China

In-network caching is one of the most important issues in content centric networking （CCN）, which may extremely influence the performance of the caching system. Although much work has been done for in-network caching scheme design in CCN, most of them have not addressed the multiple network attribute parameters jointly during caching algorithm design. Hence, to fill this gap, a new in-network caching based on grey relational analysis （GRA） is proposed. The authors firstly define two newly metric parameters named request influence degree （RID） and cache replacement rate, respectively. The RID indicates the importance of one node along the content delivery path from the view of the interest packets arriving The cache replacement rate is used to denote the caching load of the node. Then combining hops a request traveling from the users and the node traffic, four network attribute parameters are considered during the in-network caching algorithm design. Based on these four network parameters, a GRA based in-network caching algorithm is proposed, which can significantly improve the performance of CCN. Finally, extensive simulation based on ndnSIM is demonstrated that the GRA-based caching scheme can achieve the lower load in the source server and the less average hops than the existing the betweeness （Betw） scheme and the ALWAYS scheme.

关键词： CCN in-network caching request influence degree cache replacement rate grey relational analysis

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A Unified Framework for Wireless Connectivity Study subject to General Interference Attack

A Unified Framework for Wireless Connectivity Study subject ...

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IEEE International Conference on Communications

作者： Yang Liu Chengzhi Li Changchuan Yin Huaiyu Dai Beijing Key Laboratory of Network System Architecture Convergence Beijing University of Posts and Telecommunications Beijing China Department of Electrical and Computer Engineering North Carolina State University Raleigh NC

Connectivity is crucial to ensure information availability and survivability for wireless networks. In this paper, we propose a unified framework to study the connectivity of wireless networks under a general type of interference attack, which can address diverse applications including Cognitive Radio, Jamming attack and shadowing effect. By considering the primary users, jammers and deep fading as unified Interferers, we investigate a 3-dimensional connectivity region, defined as the set of key system parameters - the density of users, the density of Interferers and the interference range of Interferers - with which the network is connected. Further we study the impact of the Interferers' settings on node isolation probability, which is a fundamental local connectivity metric. Through percolation theory, the sufficient and necessary conditions for global connectivity are also derived. Our study is supported by simulation results.

关键词： Interference Three-dimensional displays Jamming Wireless networks Security Shadow mapping Information systems

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Performance Analysis of DF Relaying with Optimum Combining in a Poisson Field of Interferers

Performance Analysis of DF Relaying with Optimum Combining i...

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IEEE International Conference on Communications

作者： Navod Suraweera Norman C. Beaulieu Department of Electrical and Computer Engineering University of Alberta School of Information and Communication Engineering and Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecomunications (BUPT)

ISBN: (纸本)9781467364300

The performance of optimum combining (OC) in decode-and forward (DF) relaying in the presence of a Poisson field of interferers is analyzed. An approximation for the outage probability of the OC receiver is derived by considering the temporal correlation of the interference. Despite the randomness of the number and the locations of the interferers, the OC receiver suppresses the interference at the destination node and diversity gains are achieved, provided that the relay nodes are noise limited. For single-antenna relay nodes, the end-to-end performance is vulnerable to interference at the relay nodes which is not canceled, resulting in zero diversity gains.

关键词： DF relaying Interference Optimum combining Outage probability Poisson point processes

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Distributed user association for delay-load tradeoffs in energy harvesting enabled HetNets

Distributed user association for delay-load tradeoffs in ene...

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IEEE Wireless Communications and networking Conference Workshops (WCNCW)

作者： Hongzhang Xu Tiankui Zhang Zhimin Zeng Dantong Liu Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China School of Electronic Engineering and Computer Science Queen Mary University of London London UK

ISBN: (纸本)9781479987610

Energy harvesting is an emerging technology to save on-grid power and reduce carbon emissions in wireless communications. Terminals can utilize renewable energy obtained from environment by energy harvesting facilities. This paper investigates user association problem under a flow-level traffic model in energy harvesting enabled heterogeneous networks. In this paper, all the base stations are equipped with energy harvesting facilities and assumed to be solely powered by renewable energy. The average traffic delay is denoted using queuing theory, and a fairness index is redefined to evaluate the level of load balancing. Then a convex optimization problem is formulated in order to reduce average traffic delay and improve load balancing level. To this end, an iterative algorithm completed by user and base station respectively is proposed. Simulation results show that the user association algorithm improves the load balancing level with limited sacrifice on average traffic delay compared with the existing delay-optimal algorithm, and enables a flexible tradeoff between the average traffic delay and load balancing.

关键词： Load management Delays Indexes Energy harvesting Wireless communication Load modeling Renewable energy sources

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Discretization of an square electromagneic cloak based on transformation optics

Discretization of an square electromagneic cloak based on tr...

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International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications (MAPE)

作者： Li Deng Weijun Hong Shufang Li Jianfeng Zhu Biao Peng Botao Feng Biao Peng Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China Beijing University of Posts and Telecommunications Beijing Beijing CN Shenzhen University Shenzhen Guangdong CN

ISBN: (纸本)9781467374422

Existing discrete electromagnetic cloaks are often limited to circular shape and always based on one dimensional discretization of radius variable in cylindrical coordinates. In this paper, we proposed a two dimensional (2D) discrete square invisible cloak which really does not require any continuous constitutive material parameters. The discrete square cloak consists of several homogeneous blocks, and they are discretized from the original transform medium whose material parameters are often continuous spatial functions of both x and y variables in Cartesian coordinates. With proper design of numbers of blocks, we demonstrated the scattering properties of the proposed cloaking structure through rigorous analysis of the scattered electromagnetic fields. The proposed cloaking structure could be possibly realized, therefore may lead to a practical path to an experimental demonstration of electromagnetic cloaking.

关键词： Manganese Scattering Lead Indexes Optics Metamaterials

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The Relation of Energy-Consumption and the Population of People

The Relation of Energy-Consumption and the Population of Peo...

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International Conference on Cyber-Enabled Distributed Computing and Knowledge Discovery, CyberC

作者： HongLiang Liang HongYan Cui Key Lab of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing P.R. China State Key Lab. Of Networking and Switching Technology MIT SENSEable City Laboratory

ISBN: (纸本)9781467392013

Reducing the energy consumption of cellular wireless access networks is not only beneficial for the global environment but also makes commercial sense for telecommunication operators, our research focus on how to put forward a constructive energy saving method in the precondition of guaranteed service quality for customer. In this paper, we based on the signaling data and location data coming from one of Chinese main operator's customers, trying to analysis the law that with the increase of users in a district, how their demand for energy change. Through the use of the law, operators can make a basis when conducting the construction of the base station at the time of city expansion and the redundancy phenomenon of construction of base station can be effectively reduced and then make contributions to energy saving, the law can also be used to provide a reference for city Planning Bureau when they conducting the urban planning and the construction of Green city and then get the purpose of optimal allocation of resources. In our study, we carry out the statistics of 1558053 users from Chongqing city, finally we found that with the increase of customer' number of each special district, the number of total traffic in the city present a change of power function.

关键词： Base stations Business Mathematical model Cities and towns Correlation Internet Urban planning

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User cooperative erasure recovery in E-MBMS based on network coding 10

User cooperative erasure recovery in E-MBMS based on network...

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10th International Conference on Wireless Communications, networking and Mobile Computing, WiCOM 2014

作者： Gao, Wenting Hao, Jianjun Guo, Yijun Beijing Key Laboratory of Network System Architecture and Convergence BUPT Beijing China

ISBN: (纸本)9781849198455

Recent years wireless networks have witnessed an explosive growth in enhanced multimedia broadcast and multicast service (eMBMS). Scalable video coding (SVC) streaming is a mainstream coding in eMBMS. In this paper we present a novel eMBMS user cooperative erasure recovery mechanism based on network coding where SVC streaming and layer network coding are broadcasted by source node. Local cooperative repair together with network coding is used to save total overhead of links and reduce the retransmission times, for purpose of improving Quality of Service (QoS) of video streaming. The simulation results show that the number of retransmissions declines a lot through our mechanism. Local user cooperation saves link overhead as much as 55% when sender disseminates SVC streaming. Combining with layer network coding, the overhead can also be reduced about 17%.

关键词： Recovery

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