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SWN: An SDN Based Framework for Carrier Grade WiFi networks

China Communications 2016年第3期13卷 12-26页

作者： LEI Tao WEN Xiangming LU Zhaoming ZHAO Xing LI Yangchun ZHANG Biao Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing Laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications

With the rapid growth of mobile data traffic and vast traffic offloaded from cellular network, Wi-Fi has been considered as an essential component to cope with the tremendous growth of mobile data traffic. Although operators have deployed a lot of carrier grade Wi-Fi networks, but there are still a multitude of arrears for nowadays Wi-Fi networks, such as supporting seamless handover between APs, automatic network access and unified authentication, etc. In this paper, we propose an SDN based carrier grade Wi-Fi network framework, namely SWN. The key conceptual contribution of SWN is a principled refactoring of Wi-Fi networks into control and data planes. The control plane has a centralized global view of the whole network, can perceive the underlying network state by network situation awareness(NAS) technique, and bundles the perceived information and network management operations into northbound Application Programming Interface(API) for upper applications. In the data plane, we construct software access point(SAP) to abstract the connection between user equipment(UE) and access point(AP). Network operators can design network applications by utilizing these APIs and the SAP abstraction to configure and manage the whole network, which makes carrier grade Wi-Fi networks more flexible, user-friendly, and scalable.

关键词： SWN carrier grade Wi-Finet works SDN seamless handover load balancing Hotspot 2.0 traffic offloading

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Reduced frame set on wireless distorted video for quality assessment

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The Journal of China Universities of Posts and Telecommunications 2016年第4期23卷 77-82,100页

作者： Shao Hua Wen Xiangming Lu Zhaoming Chen Yawen Lu Jingyu Beijing Laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

Objective video quality assessment methods often evaluate all the frames regardless of their importance. For wireless distorted videos, not every frame has the same contribution to the final overall quality due to the channel fading and interference, which may lead to the capacity variation in temporal. Besides, with the content similarity and error propagation pattern in temporal domain, it is possible to evaluate the overall quality with only part of the frames. In this paper, a demonstration is performed to show that the video quality can be evaluated with reduced frames set（RFS）, and a state transition model is proposed to extract the RFS. At last, a video quality assessment（VQA） method is carried out based on RFS. Compared with several state-of-the-art methods, our method can achieve a suitable accuracy with less frames to be processed.

关键词： VQA wireless distortion quality of experience

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Energy efficient channel sharing and power optimization for device-to-device networks

Lecture Notes of the Institute for Computer Sciences, Social...

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Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering, LNICST 2017年 174卷 63-75页

作者： Xi, Zeguo Wen, Xiangming Lu, Zhaoming Zeng, Yan Hu, Zhiqun Lei, Tao Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing100876 China Beijing Laboratory of Advanced Information Networks Beijing100876 China

In device-to-device (D2D) networks, the system performance can be significantly improved with a well resource allocation scheme. In this paper, the issue of channel sharing and power allocation for deviceto-device (D2D) communications underlaying cellular networks is considered. The users with the same service content are categorized into clusters, with clusters sharing the frequency of the uplink users. With this non-orthogonal frequency sharing, the energy efficiency of different type of users, i.e., the uplink users or the D2D users, is analysed. The energy-efficient resource sharing problem is further formulated into a non-transferable coalition formation game, and several related factors of the game is described. A distributed coalition formation game algorithm based on the merge and split rule is proposed. With numerical results, the effectiveness of the game model and the algorithm is demonstrated. © ICST Institute for Computer Sciences, Social Informatics and Telecommunications Engineering 2017.

关键词： Energy efficiency

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Zone Coordinates: A New Coordinate system

Zone Coordinates: A New Coordinate System

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2017 17th IEEE International Conference on Communication Technology (ICCT 2017)

作者： Zehua Gao Mingjing Zhu Yuxi Tan School of Information and Communication Engineering Beijing Laboratory of Advanced Information NetworksBeijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

Coordinates systems include rectangular coordinate systems, cylindrical coordinate systems, and spherical coordinate systems, among others. In three-dimensional rectangular coordinate systems, "x = 2" defines a plane, "x = 2,y = 3" defines a line, and "x = 2, y = 3, z = 1" defines a ***, traditional coordinates systems are represented by the combination of point, line, and plane. In the real world,every object or field occupies a certain volume, even atoms or protons. We present a new coordinate system, called the zone coordinate system, that gives the position of an entire object or field. The zone coordinate system is more in line with reality. It can be applied in every field that requires a location-based application.

关键词： rectangular coordinate point-line coordinates zone coordinate

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A Dynamic Multiuser Detection Scheme for Uplink SCMA system

A Dynamic Multiuser Detection Scheme for Uplink SCMA System

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2017 17th IEEE International Conference on Communication Technology (ICCT 2017)

作者： Yuxi Tan Zehua Gao Siyan Guo Feng Gao School of Information and Communication Engineering Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

As one of nonorthogonal multiple access techniques for the fifth generation mobile communications, sparse code multiple access（SCMA） can provide a better link performance than other schemes in different network scenarios. However, SCMA employs message passing algorithm（MPA） as its receiver decoding scheme which leads to higher computing complexity and restricts it’s application to low latency networks. Based on this, a dynamic message passing algorithm（DMPA） is presented in this paper for reducing calculation complexity of original MPA. In DMPA, reliability of variable node can be calculated by the pseudo posterior probability after predetermined iterations, and then messages are propagated merely in subgraph of original factor graph which can result in a significant reduction in complexity. Simulation results show that DMPA can reduce decoding complexity about 37% than MPA with negligible bit error rate（BER） degradation.

关键词： SCMA（Sparse Code Multiple Access） MPA（Message Passing Algorithm） BER（Bit error rate） complexity

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A Spatial Dimming Scheme Based on Transmit Antenna Selection for Multiuser MISO VLC systems

A Spatial Dimming Scheme Based on Transmit Antenna Selection...

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International Conference on Communications Workshops

作者： Zhen Feng Caili Guo Yang Yang Chunyan Feng Beijing Laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications China Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications China

ISBN: (纸本)9781509015269

The multi-user multiple-input single-output (MU-MISO) visible light communications (VLC) system, which can serve multi-users simultaneously, have been widely studied in recent years. Dimming control is one of the main topics in VLC systems. In this paper, we proposed a novel transmit antenna selection based spatial dimming (TAS-SD) scheme for zero forcing (ZF) precoded MU-MISO VLC systems. By taking full advantage of the channel state information at both the transmitter and the users, the proposed TAS-SD scheme can combine the precoding and transmit antenna selection (TAS) technique together, and effectively improves the performance of dimmable MU-MISO systems. Simulation results show that the proposed TAS-SD scheme has significant bit error-ratio performance gains over the conventional analog dimming (AD) scheme at various dimming proportions and user positions. These advantages make it a promising candidate dimming scheme for ZF precoded MU-MISO VLC systems.

关键词： Multiuser MISO VLC

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Research and Analysis of Browsing Habits of New Media Audiences on the Chinese Campus

Research and Analysis of Browsing Habits of New Media Audien...

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2017 2nd International Conference on Wireless Communication and Network Engineering(WCNE 2017)

作者： Dong-jun HAN Qiu-jian LV Jie YANG Center for Data Science Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture and ConvergenceBUPT Institute of Information Engineering Chinese Academy of Sciences

Audience research is such a hit nowadays, and always has been based on web logs modeling. However, the content data of articles has not been considered yet. So, this paper clusters the ordered word vectors of an article to analyze audiences browsing habits of Chinese campus. This paper first obtains the contents and page views of articles from We Chat official accounts of several Chinese campuses. Then, it analyzes the audiences by clustering the ordered word vectors of the articles they have been read. To do so, the articles are first converted into a word vector model through Jieba word segmentation and word2vec, and then TF-IDF is applied for weight sequencing. Finally, the distances between articles are obtained by calculating the mean sum of square of the distances between words. Also, we cluster contents according to their topics and obtain many meaningful results. This paper provides a new method of audience analysis based on semantic, which can simplify the manual classification process of articles, and provide more comprehensive analysis conclusions. Moreover, these analysis results are useful for the strategy of content production and precious marketing.

关键词： Campus new media Audience analysis Word vector Article clustering

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Consistent-estimated eigenvalues based cooperative spectrum sensing for dense cognitive Small Cell Network

Consistent-estimated eigenvalues based cooperative spectrum ...

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IEEE International Conference on Communications Workshops, ICC

作者： Meng Zhao Caili Guo Chunyan Feng Shuo Chen Beijing Laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China

ISBN: (纸本)9781509015269

In this paper, we consider the spectrum sensing problem of detecting a primary signal of a macro cell in a cognitive radio network by employing multiple dense small cell base stations. In consideration of the number of cooperative small cells (sample dimension) is comparable to the number of sample (sample size) due to the dense deployment of small cells, sample covariance matrix is no more a good estimator of statistical covariance matrix. A consistent-estimated eigenvalues based cooperative spectrum sensing (CEE-CSS) algorithm is proposed by utilizing consistent estimators of eigenvalues which are proven to be consistent when the sample dimension goes to infinity at the same rate as sample size. Effect of the eigenvalue splitting condition on sensing performance of the CEE-CSS is analyzed through simulations. Further simulation results present that the proposed CEE-CSS enables better sensing performance than a maximum-minimum eigenvalue detection based on oracle approximating shrinkage estimator (OAS-MME).

关键词： Sensors Eigenvalues and eigenfunctions Covariance matrices Microprocessors Computer architecture Market research Estimation

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Analyzing human mobility and social relationships from cellular network data

Analyzing human mobility and social relationships from cellu...

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International Conference on Network and Service Management

作者： Zheng Liu Yuanyuan Qiao Siyan Tao Wenhui Lin Jie Yang BUPT Beijing Key Laboratory of Network System Architecture and Convergence and Beijing Laboratory of Advanced Information Networks Beijing China Technology Research Institute Aisino Corporation Beijing China

Due to geographic and social constraints, human mobility shows a high degree of temporal and spatial regularity. More recently, emerging data tagged with geographical information can be used to study human mobility patterns. People usually spend most of their time at a few key important locations, such as home and work places. And for users with a certain social connection-co-workers or co-life, they often stay at the same locations. In this paper, firstly, we use an algorithm to identify important locations. After that, we find that the similarity between the two trajectories is closely related to their proximity in the location-based social network, where users having the same important locations are connected. In order to embody social contacts in mobility, for hourly variations in mobility similarity, we apply unsupervised clustering method to identify four categories of social ties. Finally, we further propose the unsupervised method and supervised method to predict which new links will develop in a social location-based network. We believe our finding can contribute to urban planning especially in areas of functional zone, transportation infrastructure deployment and mobile network facilities development.

关键词： Social network services Base stations Correlation Mobile computing Trajectory Cellular networks

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COFFEE-CUP: A cost-efficient routing strategy for delay tolerant networks using time-varying community partitioning 13

COFFEE-CUP: A cost-efficient routing strategy for delay tole...

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13th International Symposium on Wireless Communication systems, ISWCS 2016

作者： Lin, Guoping Liao, Qing Can, Deng Tianyi, Wang Zhao, Jingling Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China

ISBN: (纸本)9781509020614

Delay Tolerant networks are a special kind of ad hoc networks that consist of a number of mobile devices. In DTNs, network topology frequently changes and source-to-destination communication paths can hardly be sustained. However, some social features have been observed in DTNs by analyzing the real mobile trajectories of DTNs. To utilize these social features to facilitate data routing, we present a community-based routing protocol that efficiently detects the community structure by using proposed time-varying community partitioning algorithm. For intracommunity routing, according to the remaining time-to-live of the message, the minimum number of message copies necessary to achieve a given delivery probability is calculated, which is the number of message copies utilized to spray in the current community. To facilitate intercommunity routing, we choose the gateway node that connects the next community frequently as relay. The evaluation of our strategy is conducted by extensive traced-driven simulations. The results of simulations confirm the effectiveness of our routing strategy. © 2016 IEEE.

关键词： Delay tolerant networks

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