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13th International Symposium on Wireless Communication systems, ISWCS 2016

作者： Yan, Zeng Wen, Xiangming Lu, Zhaoming Chen, Yawen Shao, Hua Beijing Laboratory of Advanced Information Networks Beijing Advanced Innovation Center for Future Internet Technology Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing100876 China

ISBN: (纸本)9781509020614

The cloud radio access network (C-RAN) has emerged as a promising architecture to provide extremely high throughput with fantastic energy efficiency (EE) performance. However, as all the RRHs need to be connected to the baseband unit pool (BBU) through transport links, the transmit power consumption becomes significant, which result in the demands of new researches in energy efficiency optimization. In this paper, we focus on the dynamic remote radio head (RRH) activation and network EE optimization in order to fully reap the benefits brought by Green C-RAN. First, an EE optimization problem that jointly considers RRH activation and group sparse beamforming is formulated, which is hard to solve due to its non-convexity nature. Thus, we utilize the weighted minimal mean square error (WMMSE) method to transfer the non-convex EE problem into a concave-convex fractional program problem. And the Lagrangian theory is exploited to assist the problem analysis and algorithm design. Specifically, the weighted group sparse beamforming algorithm is proposed. In this algorithm, we adopt the mixed l1=lp-norm to induce group sparsity in the beamformers, which corresponds to switching off RRHs. Simulation results will show that the proposed algorithm can significantly improve the EE for C-RAN. © 2016 IEEE.

关键词： Energy efficiency

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A fair listen-before-talk mechanism for LTE-U using a coalition formation approach 13

A fair listen-before-talk mechanism for LTE-U using a coalit...

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13th International Symposium on Wireless Communication systems, ISWCS 2016

作者： Wuqiong, Ding Wen, Xiangming Lu, Zhaoming Wenpeng, Jing Yan, Zeng Beijing Key Laboratory of Network System Architecture and Convergence Beijing Advanced Innovation Center for Future Internet Technology Beijing Laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications Beijing100876 China

ISBN: (纸本)9781509020614

LTE on unlicensed bands (LTE-U), which is a promising way to meet the increasing mobile data demand, has attracted world-wide interests. However, the fair coexistence of LTE-U and WLAN is a critical issue to be solved. In this paper, we devise a semi-distributed channel access approach for LTE-U in dense deployed scenario to improve its capacity and achieve fair coexistence with WLAN. Specifically, the basic listen-before-talk (LBT) mechanism is employed to guarantee the fairness for WLAN, which is similar with the medium control access (MAC) protocol of WLAN. However, in order to decrease the high collision probability at heavy traffic load, a coalition strategy is introduced, in which the LTE-U base stations (BSs) would form into groups, and each group would contend for accessing the channel as one entity. This will effectively reduce the number of stations contending for accessing the channel and the collision probability as a result. In particular, in order to obtain the coalition solution, the cooperative game theory is introduced, and a low-complexity coalition formation algorithm is proposed based on the concept of recursive core in cooperative game. Simulation results verify the effectiveness of the proposed channel access approach, especially improving the LTE-U capacity and ensuring the fairness between LTE-U and WLAN. © 2016 IEEE.

关键词： Medium access control

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Oscillation resolution for massive cell phone traffic data 1

Oscillation resolution for massive cell phone traffic data

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1st Workshop on Mobile Data, MobiData 2016, co-located with MobiSys 2016

作者： Qi, Ling Qiao, Yuanyuan Abdesslem, Fehmi Ben Ma, Zhanyu Yang, Jie Center for Data Science Beijing Key Laboratory of Network System Architecture and Convergence Beijing Laboratory of Advanced Information Network BUPT Beijing China Decisions Networks and Analytics Laboratory SICS Stockholm Sweden Center for Data Science Pattern Recognition and Intelligent System Lab BUPT Beijing China

ISBN: (纸本)9781450343275

Cellular towers capture logs of mobile subscribers whenever their devices connect to the network. When the logs show data traffic at a cell tower generated by a device, it reveals that this device is close to the tower. The logs can then be used to trace the locations of mobile subscribers for different applications, such as studying customer behaviour, improving location-based services, or helping urban planning. However, the logs often suffer from an oscillation phenomenon. Oscillations may happen when a device, even when not moving, does not only connect to the nearest cell tower, but is instead unpredictably switching between multiple cell towers because of random noise, load balancing, or simply dynamic changes in signal strength. Detecting and removing oscillations are a challenge when analyzing location data collected from the cellular network. In this paper, we propose an algorithm called SOL (Stable, Oscillation, Leap periods) aimed at discovering and reducing oscillations in the collected logs. We apply our algorithm on real datasets which contain about 18.9 TB of traffic logs generated by more than 3 million mobile subscribers covering about 21000 cell towers and collected during 27 days from both GSM and UMTS networks in northern China. Experimental results demonstrate the ability and effectiveness of SOL to reduce oscillations in cellular network logs. © 2016 ACM.

关键词： Location based services

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A modified Matérn hard core point process for modeling and analysis of dense IEEE 802.11 networks 13

A modified Matérn hard core point process for modeling and ...

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13th International Symposium on Wireless Communication systems, ISWCS 2016

作者： Tao, Lei Wen, Xiangming Lu, Zhaoming Jing, Wenpeng Chen, Kun Zhao, Xiaoguang Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China Beijing Laboratory of Advanced Information Networks Beijing China Beijing Advanced Innovation Center for Future Internet Technology China

ISBN: (纸本)9781509020614

Stochastic geometry is a powerful tool for modeling wireless networks employing various MAC protocols with random topologies. For wireless networks operating carrier sense multiple access/collision avoidance (CSMA/CA) protocol, there are distance constraints between simultaneous transmitters, and only one node is allowed to transmit within its carrier sensing range. Matérn hard core point process is generally used to model and analyze the performance of this type of networks, because it is a repulsive point process that also defines a minimum distance between any two points. However, the traditional Matérn HCPP has the defect of underestimating the intensity of concurrent transmission nodes, which will affect the accuracy of analysis results, when wireless nodes are densely deployed. In this paper, we propose a modified Matérn HCPP called TM-HCPP which can mitigate the intensity underestimation problem to model dense IEEE 802.11 networks. Then, we simulate the network coverage probability using the traditional Matérn HCPP and the proposed TM-HCPP, and compare the simulated results with the theoretical analyzed results. Simulation results validate the accuracy of the proposed TM-HCPP. © 2016 IEEE.

关键词： Wireless networks

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Diffraction loss of mobile communications electromagnetic wave in L-corridor

Diffraction loss of mobile communications electromagnetic wa...

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IEEE International Symposium on Electromagnetic Compatibility (EMC-beijing)

作者： Feng Zhou Zhen Ma Hai-Man Zhang Feng Gao Xiu-Hua Yuan Xiang-Yang Zhang China Academy of Information and Communication Technology Beijing China Network Optimization Center China Mobile Communications Group Shan-xi Co. Ltd. Xi-an China School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing Beijing CN Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing Beijing CN

Diffraction loss exists in the corner of L-corridor in buildings. Both measurement and simulation show that conventional diffraction propagation model does not fit L-corridor. The diffraction loss increases linearly w... 详细信息

关键词： Diffraction Loss measurement Propagation losses Frequency measurement Transmitting antennas Mathematical model Receiving antennas

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Handoff management scheme based on frame loss rate and RSSI prediction for IEEE 802.11 networks 13

Handoff management scheme based on frame loss rate and RSSI ...

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13th International Symposium on Wireless Communication systems, ISWCS 2016

作者： Tao, Lei Wen, Xiangming Lu, Zhaoming Wenpeng, Jing Biao, Zhang Gang, Cao Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China Beijing Laboratory of Advanced Information Networks Beijing China Beijing Advanced Innovation Center for Future Internet Technology China

ISBN: (纸本)9781509020614

This paper proposes a frame loss rate (FLR) and received signal strength indicator (RSSI) prediction based handoff management scheme to reduce the ping-pong effect caused by the purely RSSI based handoff decision schemes in IEEE 802.11 networks. The proposed scheme is performed by each mobile station (MS) in a decentralized manner. In the proposed scheme, the FLR information is used as handoff trigger criterion. To perceive the change trends of wireless link thus reducing the target AP selection time, the proposed scheme adopts polynomial regression-based RSSI prediction approach. The predicted RSSI together with FLR information is used for target access point (AP) selection. Moreover, we construct neighboring AP information list (NAIL) for MSs to store the above information. Therefore, the proposed scheme can also be called NAIL-based handoff management scheme. The results indicate that the proposed scheme can effectively reduce the invalid handoffs and avoid the ping-pong effect. © 2016 IEEE.

关键词： Forecasting

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A Terahertz RF Selective Switch Based on Graphene

A Terahertz RF Selective Switch Based on Graphene

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IEEE International Conference on Internet of Things

作者： Xiaoyuan Ma Weijun Hong Li Deng Shufang Li Liang Yin Beijing Key Laboratory of Network System Architecture and Convergence

ISBN: (纸本)9781509058815

According to the variable conductivity of the graphene and the principle of surface acoustic wave, a new type of 30THz three billing graphene frequency selective switch is proposed in this paper. The selection switch has 3 selection paths. By controlling the conductivity of graphene, we can change the refractive index of the intermediate graphene lens, then change the direction of the plane wave and choose signal pathway flexibly. There is a good isolation between the output ports, the minimum value can reach -30dB. And the attenuation of signal input and output is about -10dB. On the whole, the selection switch has the characteristics of scalable, tunable, and high isolation,has a greater inspiration for graphene device design in the future.

关键词： terahertz graphene conductivity frequency selective switch

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Echo state transfer learning for data correlation aware resource allocation in wireless virtual reality

arXiv

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arXiv 2017年

作者： Chen, Mingzhe Saad, Walid Yin, Changchuan Debbah, Mérouane Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing100876 China Wireless-VT Bradley Department of Electrical and Computer Engineering Virginia Tech BlacksburgVA United States Mathematical and Algorithmic Sciences Lab Huawei France R & D Paris France

In this paper, the problem of data correlation-aware resource management is studied for a network of wireless virtual reality (VR) users communicating over cloud-based small cell networks (SCNs). In the studied model, small base stations (SBSs) with limited computational resources act as VR control centers that collect the tracking information from VR users over the cellular uplink and send them to the VR users over the downlink. In such a setting, VR users may send or request correlated or similar data (panoramic images and tracking data). This potential spatial data correlation can be factored into the resource allocation problem to reduce the traffic load in both uplink and downlink. This VR resource allocation problem is formulated as a noncooperative game that allows jointly optimizing the computational and spectrum resources, while being cognizant of the data correlation. To solve this game, a transfer learning algorithm based on the machine learning framework of echo state networks (ESNs) is proposed. Unlike conventional reinforcement learning algorithms that must be executed each time the environment changes, the proposed algorithm can intelligently transfer information on the learned utility, across time, to rapidly adapt to environmental dynamics due to factors such as changes in the users' content or data correlation. Simulation results show that the proposed algorithm achieves up to 16.7% and 18.2% gains in terms of delay compared to the Q-learning with data correlation and Q-learning without data correlation. The results also show that the proposed algorithm has a faster convergence time than Q-learning and can guarantee low delays. Copyright © 2017, The Authors. All rights reserved.

关键词： Virtual reality

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Research and Comparative Analysis of Performance Test on SDN Controller

Research and Comparative Analysis of Performance Test on SDN...

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2016 First IEEE International Conference on Computer Communication and the Internet

作者： Fan Yamei Liao Qing He Qi School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence China Telecom Corporation Limited Beijing Research Institute

ISBN: (纸本)9781467385169

The emergence of Software Defined network(SDN)gives the demand of big data and network management a *** separates the control and forwarding in traditional network through OpenF low *** the software-defined network,SDN controller is an important integral part that is the core of *** this paper,firstly we summarize the common SDN controller,and choose two popular,wider using open-source controllers(OpenD aylight and ONOS),analyze the implementation architecture and model framework of the two *** build the controller platform,simulate the underlying topology using IXIA test instruments,Cbench and Mininet to get the performance parameters and furthermore analyze the data.

关键词： SDN Test OpenDaylight ONOS

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Research and comparative analysis of performance test on SDN controller 1

Research and comparative analysis of performance test on SDN...

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1st IEEE International Conference on Computer Communication and the Internet, ICCCI 2016

作者： Fan, Yamei Qing, Liao Qi, He School of Information and Communication Engineering Beijing University of Posts and Telecommunications 100876 China Beijing Key Laboratory of Network System Architecture and Convergence Beijing100876 China China Telecom Corporation Limited Beijing Research Institute Beijing102209 China

ISBN: (纸本)9781467385145

The emergence of Software Defined network(SDN) gives the demand of big data and network management a chance. SDN separates the control and forwarding in traditional network through OpenFlow protocol. In the software-defined network, SDN controller is an important integral part that is the core of SDN. In this paper, firstly we summarize the common SDN controller, and choose two popular, wider using open-source controllers(OpenDaylight and ONOS), analyze the implementation architecture and model framework of the two controllers. Then build the controller platform, simulate the underlying topology using IXIA test instruments, Cbench and Mininet to get the performance parameters and furthermore analyze the data. © 2016 IEEE.

关键词： Controllers

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