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International Conference on Computer and Communications (ICCC)

作者： Kai Zhang Changchuan Yin Jin Xu Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing China

Traditional handover algorithms are based on received signal strength indicator (RSSI) and traffic load intensity in orthogonal frequency division multiple access (OFDMA) systems, in order to guarantee all UEs' Quality of Service (QoS) and handover success ratio, a transceiver is activated even if there is only one low date rate activated user in its coverage area. In this paper, we propose an energy efficient handover algorithm combined coordinated multiple-points (CoMP) with OFDMA in a cellular systems, energy efficiency is introduced into the handover algorithm as an important parameter. The idea of the design is to enable adjacent cells to shutdown partial transceivers in some timeslots in low traffic conditions by concentrating the activated edge UEs to less cells. All activated UEs are classified into edge users and center users according to their distance to base stations, the analysis indicates that there exist an optimal edge distance corresponding to the maximum energy efficiency under different load for the proposed algorithm. Furthermore, a practical and low-complexity scheme that only considers the edge users is put forward. The edge users are identified by the reference signal received power (RSRP). Simulation results show that it can obtain up to 60% energy reduction at low traffic scenario.

关键词： Handover Power demand Base stations Energy efficiency Telecommunication traffic Algorithm design and analysis

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Performance improvement for applying network virtualization in fiber-wireless(FiWi) access networks

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第11期15卷 1058-1070页

作者： Qing-long DAI Guo-chu SHOU Yi-hong HU Zhi-gang GUO Beijing Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications

Fiber-wireless(FiWi) access networks, which are a combination of fiber networks and wireless networks,have the advantages of both networks, such as high bandwidth, high security, low cost, and flexible access. However,with the increasing need for bandwidth and types of service from users, FiWi networks are still relatively incapable and ossified. To alleviate bandwidth tension and facilitate new service deployment, we attempt to apply network virtualization in FiWi networks, in which the network's control plane and data plane are separated from each *** on a previously proposed hierarchical model and service model for FiWi network virtualization, the process of service implementation is described. The performances of the FiWi access networks applying network virtualization are analyzed in detail, including bandwidth for links, throughput for nodes, and multipath flow *** results show that the FiWi network with virtualization is superior to that without.

关键词： FiWi access networks network virtulization Performance analysis

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Performance Study of Relay Coordination Schemes for Two-Hop networks: Two-Cell Case

Performance Study of Relay Coordination Schemes for Two-Hop ...

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IEEE International Conference on Communications

作者： Kasun T. Hemachandra Norman C. Beaulieu Department of Electrical and Computer Engineering University of Alberta School of Information and Communication Engineering and the Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

ISBN: (纸本)9781467364300

The outage probability of a two-hop coordinated decode-and-forward relay network is investigated. Relay coordination is performed only with the dominant interferer. Different levels of network coordination are studied and their performances are compared. Exact expressions are derived for the outage probability of a particular mobile user for each coordination scheme. Asymptotic outage probability is derived to identify the diversity and coding gains for each coordination scheme.

关键词： Cochannel interference Decode-and-forward Outage probability Relay coordination Zero-forcing

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Accurate network Resource Allocation in SDN according to Traffic Demand

Accurate Network Resource Allocation in SDN according to Tra...

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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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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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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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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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