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International Symposium on Wireless Personal Multimedia Communications (WPMC)

作者： Xi Chen Hailun Xia Zhimin Zeng Shie Wu WenQi Zuo Yao Lu Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China China Unicom Network Research Institute

ISBN: (纸本)9781479964123

Hierarchical layering of cells with macrocells coexisting with low-power small cells has been investigated as a promising technique to enhance coverage extension and reduce power consumption, which has emerged as a candidate for green communications. Due to the challenging interference scenarios, Cell Range Extension (CRE) and enhanced inter-cell interference coordination (eICIC) are the key technologies that make HetNets a reality. However, when macrocells and low-power nodes (LPNs) share the same spectrum, the total network throughput could actually decrease due to CRE if the inter-layer interference can't be effectively managed. In this paper, we propose an inter-layer interference coordination scheme on the downlink side for a co-channel macro-pico HetNet that carries out CRE technique. The idea of the proposed method is to coordinate frequency and power resource allocation among macrocells and picocells with a set of rules, which can lead to interference mitigation and power reduction. Then a utility function combining interference and throughput is calculated to find the optimal transmission power of each macro base station (MBS) in some special bands by using Differential Evolution (DE) theory. Finally, simulation results show that the proposed method can not only promote the system throughput and energy efficiency greatly but also keep better link quality in the system.

关键词： Interference Throughput Energy efficiency Signal to noise ratio Macrocell networks Power demand Power control

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Adaptive Polarization Modulation in Depolarization Channel with Polarization Dependent Loss

Adaptive Polarization Modulation in Depolarization Channel w...

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IEEE Vehicular Technology Conference

作者： Guangwei Yang Fangfang Liu Zhimin Zeng Chunyan Feng Wen Zhao Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications

ISBN: (纸本)9781479944484

To adapt to variation of polarization dependent loss (PDL) in depolarization channel, an adaptive polarization modulation scheme which can improve the spectral efficiency of polarization modulation system is proposed. In the proposed scheme, the transmitter adapts the optimal constellation size to the variation of the channel due to PDL while fulfilling a fixed target BER constraint, which is based on the received feedback information of channel state information estimated at the receiver. Our simulation results and analysis show that, adaptive polarization modulation (APM) can achieve higher spectral efficiency (SE) than nonadaptive polarization modulation, subject to the same fixed target BER constraint.

关键词： Polarization dependent loss Adaptive polarization modulation Spectral efficiency

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HADOOP-BASED network TRAFFIC ANOMALY DETECTION IN BACKBONE

HADOOP-BASED NETWORK TRAFFIC ANOMALY DETECTION IN BACKBONE

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2014 IEEE 3rd International Conference on Cloud Computing and Intelligence systems

作者： Jishen Yu Feng Liu Wenli Zhou Hua Yu Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications

This paper presents a distributed system for real-time anomaly detection in *** backbone traffic is so huge that it is difficult to monitor abnormal traffic by traditional *** system is based on Hadoop,an open source framework,and used to detect the abnormal ***,We establish a precise regression model to describe the network ***,distributed system Hadoop is used to detect the abnormal ***,the experimental results prove that our system can detect the abnormal traffic accurately and efficiently in the real-world network environment.

关键词： Anomaly Detection traffic mode Hadoop backbone

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Dynamic Spectrum Sharing for TD-LTE and FD-LTE users based on Joint Polarization Adaption and Beamforming

Dynamic Spectrum Sharing for TD-LTE and FD-LTE users based o...

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IEEE Vehicular Technology Conference

作者： Dongming Li Caili Guo Zhimin Zeng Xiaolin Lin Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications

ISBN: (纸本)9781479944811

In this work, a joint polarization adaption and beamforming technique is proposed for horizontal spectrum sharing for TD-LTE and FD-LTE users. The polarization and spatial information of multiple dual-polarized antennas on current LTE nodes is exploited to mitigate the mutual interference among the primary, TD-LTE and FD-LTE users. By this means, the opportunities in polarization and spatial domains are exploited, which means the licensed spectrum can be shared by TD-LTE and FD-LTE users with primary users simultaneously, thus the spectrum efficiency is improved. Simulation results show that the proposed technique can improve the spectrum efficiency in comparison traditional spectrum sharing approaches that utilize the spectrum opportunities in temporal domain, while acceptable interference is introduced to the primary user.

关键词： Polarization adaption Beamforming Dynamic spectrum sharing TD-LTE FD-LTE

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Spectrum Sensing Based on EDCAF of Signal in Multipath-doppler Channel

Spectrum Sensing Based on EDCAF of Signal in Multipath-doppl...

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IEEE Vehicular Technology Conference

作者： Meimei Duan Zhiming Zeng Caili Guo Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications

ISBN: (纸本)9781479944484

The communication channel is becoming more and more complicated, which increases difficulty of signal detection of the spectrum band. The performance of signal detection is degraded due to the frequency shift and fading of the doppler multipath channel. In this paper the weak signal detection based on cyclostationary property is considered and energy detection of cyclic-autocorrelation function (EDCAF) is proposed to detect the primary signal in doppler multipath channel. Simulation shows that the proposed method has better performance than that of other detection algorithms. Furthermore, the EDCAF is simple and direct, which is feasible for cognitive radio networks.

关键词： Multipath channels Channel estimation Noise Sensors Signal detection Fading Cognitive radio

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An SDN-Based Approach for Load Balance in Heterogeneous Radio Access networks

An SDN-Based Approach for Load Balance in Heterogeneous Radi...

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IEEE Symposium on Computer Applications and Communications (SCAC)

作者： Wenqiang Tang Qing Liao Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing P.R. China

The next generation of wireless networks will integrate multiple radio access technologies, which constitute the heterogeneous network. The performance of the network and user experience will depend on a good use of the radio resource heavily. With the development of mobile Internet, a large amount of intelligent terminal applications emerge. Specifically, the multimedia applications, which will take up a lot of bandwidth, present a challenge for the load capacity of the heterogeneous networks. Software Defined networking (SDN) will give us a solution to the load balancing of the radio access network (RAN). Firstly, we design a SDN-based load balancer to which we can apply different load balancing algorithm. Secondly, we propose a utility-based load balancing algorithm which can take both the RAN status and user needs into consideration. Finally, simulation results show that the RAN load can be balanced while giving users a good experience.

关键词： Radio access networks Wireless networks Algorithm design and analysis Load modeling Mobile communication Load management Standards

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A virtual network mapping algorithm based on integer programming

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第12期14卷 899-908页

作者： Bo LU Jian-ya CHEN Hong-yan CUI Tao HUANG Yun-jie LIU Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

The virtual network(VN) embedding/mapping problem is recognized as an essential question of network virtualization. The VN embedding problem is a major challenge in this field. Its target is to efficiently map the virtual nodes and virtual links onto the substrate network resources. Previous research focused on designing heuristic-based algorithms or attempting two-stage solutions by solving node mapping in the first stage and link mapping in the second stage. In this study, we propose a new VN embedding algorithm based on integer programming. We build a model of an augmented substrate graph, and formulate the VN embedding problem as an integer program with an objective function and some constraints. A factor of topology-awareness is added to the objective function. The VN embedding problem is solved in one stage. Simulation results show that our algorithm greatly enhances the acceptance ratio, and increases the revenue/cost(R/C) ratio and the revenue while decreasing the cost of the VN embedding problem.

关键词： Virtual network embedding Integer programming Topology-awareness network virtualization

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R-SDN: A recusive approach for scaling SDN

R-SDN: A recusive approach for scaling SDN

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2014 International Conference on Information and Communications Technologies (ICT 2014)

作者： Wei Dai Guochu Shou Yihong Hu Zhigang Guo School of Information and Comminicaton Engineering Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence China

Software-Defined networking provides a clean separation between control plane and data plane. In addition, control plane can configure and manage data plane in a centralized way. However, a centralized control plane introduces a problem in scaling SDN network. With the idea of network virtualization, we propose a recursive way to construct a new architecture of SDN so that the problem of scaling can be solved. A recursive algorithm is put forward to implement this new idea. As a kind of recursive model, Fibonacci series can be applied to R-SDN. Then, we take routing as typical scenario of experiment to test performance on this new architecture. Finally, we analyse experiment results based on principle and acquire some conclusions.

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Efficient load balancing multipath algorithm for fiber-wireless network virtualization

Efficient load balancing multipath algorithm for fiber-wirel...

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2014 International Conference on Information and Communications Technologies (ICT 2014)

作者： Xinrui Meng Guochu Shou Yihong Hu Zhigang Guo Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications China

The fiber-wireless network which is a combination of the fiber subnetwork and wireless subnetwork has provided high bandwidth access with ubiquity and mobility. But traditional single-path transmission cannot satisfy people's requirements for network performance due to various services. Multipath algorithms have been proposed as a solution to the network congestion. The multipath algorithm in traditional network has some limits in such heterogeneous networks. The application of network virtualization which can hide the differences of underlying physical infrastructures provides a potential method to solve this problem. In this paper we propose a Modified Weighted Round Robin (MWRR) algorithm based on the model of fiber-wireless network virtualization. Specific scheduling schemes will be arranged due to the quality of service requests and the states of links via the global view in the control plane. The simulation results show the smaller end-to-end delay and better load balancing.

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Interference alignment and bit allocation in heterogeneous networks with limited feedback

Interference alignment and bit allocation in heterogeneous n...

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International Symposium on Wireless Personal Multimedia Communications (WPMC)

作者： Qin Niu Zhimin Zeng Tiankui Zhang Qiubin Gao Shaohui Sun Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China State Key Laboratory of Wireless Mobile Communications (CATT) Beijing China

ISBN: (纸本)9781479964123

This paper focuses on downlink interference issues in the open subscriber group (OSG) mode of heterogeneous network (HetNet). In OSG mode, the inter macro-user interference is the main interference to macro user equipments (UEs), and the inter cell interference (ICI), containing the inter picocell interference and the cross-layer interference from macro base station (BS), is the main interference to pico UEs. An interference alignment (IA) scheme for such HetNet is proposed. The transceiver is designed as follows, 1) the precoding matrix for macro BS and the interference suppression matrices for macro UEs are used to eliminate the inter macro-user interference to macro UEs; 2) the precoding matrices of pico BSs are designed to align the inter picocell interference onto the space of the strongest cross-layer interference produced by macro BS; 3) the aligned interference is eliminated by the interference suppression matrices of pico UEs. In addition, the influence of imperfect channel state information at the transmitter (CSIT) on the proposed IA scheme is analyzed. By characterizing the rate loss as a function of the feedback bits number, a bit allocation scheme is given. The simulations show that the proposed scheme can reduce the requirement of the receive antennas number and improve the system throughput of HetNet.

关键词： Interference suppression Bit rate Receiving antennas Macrocell networks Vectors Wireless communication

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