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IEEE 802.11ay based mmwave WLANs: Design challenges and solutions

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arXiv 2018年

作者： Zhou, Pei Cheng, Kaijun Han, Xiao Fang, Xuming Fang, Yuguang He, Rong Long, Yan Liu, Yanping Key Lab of Information Coding & Transmission Southwest Jiaotong University Chengdu610031 China CT lab Huawei Shenzhen518129 China Department of Electrical and Computer Engineering University of Florida 435 New Engineering Building PO Box 116130 GainesvilleFL32611 United States

Millimeter-wave (mmWave) with large spectrum availab.e is considered as the most promising frequency band for future wireless communications. The IEEE 802.11ad and IEEE 802.11ay operating on 60 GHz mmWave are the two most expected wireless local area network (WLAN) technologies for ultra-high-speed communications. For the IEEE 802.11ay standard still under development, there are plenty of proposals from companies and researchers who are involved with the IEEE 802.11ay task group. In this survey, we conduct a comprehensive review on the medium access control layer (MAC) related issues for the IEEE 802.11ay, some cross-layer between physical layer (PHY) and MAC technologies are also included. We start with MAC related technologies in the IEEE 802.11ad and discuss design challenges on mmWave communications, leading to some MAC related technologies for the IEEE 802.11ay. We then elab.rate on important design issues for IEEE 802.11ay. Specifically, we review the channel bonding and aggregation for the IEEE 802.11ay, and point out the major differences between the two technologies. Then, we describe channel access and channel allocation in the IEEE 802.11ay, including spatial sharing and interference mitigation technologies. After that, we present an in-depth survey on beamforming training (BFT), beam tracking, single-user multiple-input-multiple-output (SU-MIMO) beamforming and multi-user multiple-input-multiple-output (MU-MIMO) beamforming. Finally, we discuss some open design issues and future research directions for mmWave WLANs. We hope that this paper provides a good introduction to this exciting research area for future wireless systems. Copyright © 2018, The Authors. All rights reserved.

关键词： Millimeter waves

Throughput and robustness guaranteed beam tracking for mmWave wireless networks

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arXiv 2017年

作者： Zhou, Pei Fang, Xuming Long, Yan Key Lab of Information Coding & Transmission Southwest Jiaotong University Chengdu China

With the increasing demand of ultra-high-speed wireless communications and the existing low frequency band (e.g., sub-6GHz) becomes more and more crowded, millimeter-wave (mmWave) with large spectra availab.e is considered as the most promising frequency band for future wireless communications. Since the mmWave suffers a serious path-loss, beamforming techniques shall be adopted to concentrate the transmit power and receive region on a narrow beam for achieving long distance communications. However, the mobility of users will bring frequent beam handoff, which will decrease the quality of experience (QoE). Therefore, efficient beam tracking mechanism should be carefully researched. However, the existing beam tracking mechanisms concentrate on system throughput maximization without considering beam handoff and link robustness. This paper proposes a throughput and robustness guaranteed beam tracking mechanism for mobile mmWave communication systems which takes account of both system throughput and handoff probability. Simulation results show that the proposed throughput and robustness guaranteed beam tracking mechanism can provide better performance than the other beam tracking mechanisms. Copyright © 2017, The Authors. All rights reserved.

关键词： Beamforming

Beam management for millimeter wave beamspace MU-MIMO systems

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arXiv 2017年

作者： Xue, Qing Fang, Xuming Xiao, Ming Key Lab of Information Coding and Transmission Southwest Jiaotong University Chengdu610031 China Communication Theory Department Royal Institute of Technology Stockholm100 44 Sweden

Millimeter wave (mmWave) communication has attracted increasing attention as a promising technology for 5G networks. One of the key architectural features of mmWave is the use of massive antenna arrays at both the transmitter and the receiver sides. Therefore, by employing directional beamforming (BF), both mmWave base stations (MBSs) and mmWave users (MUEs) are capable of supporting multi-beam simultaneous transmissions. However, most researches have only considered a single beam, which means that they do not make full potential of mmWave. In this context, in order to improve the performance of short-range indoor mmWave networks with multiple reflections, we investigate the challenges and potential solutions of downlink multi-user multi-beam transmission, which can be described as a high-dimensional (i.e., beamspace) multi-user multiple-input multiple-output (MU-MIMO) technique, including multi-user BF training, simultaneous users' grouping, and multi-user multibeam power allocation. Furthermore, we present the theoretical and numerical results to demonstrate that beamspace MU-MIMO compared with single beam transmission can largely improve the rate performance of mmWave systems. Copyright © 2017, The Authors. All rights reserved.

关键词： Beamforming

Modeling and analysis of non-orthogonal MBMS transmission in heterogeneous networks

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arXiv 2017年

作者： Zhang, Zhengquan Ma, Zheng Xiao, Ming Fan, Pingzhi Key Lab of Information Coding and Transmission Southwest Jiaotong University Chengdu610031 China Communication Theory Lab School of Electrical Engineering and ACCESS Linnaeus Center Royal Institute of Technology Sweden

Broadcasting/multicasting is an efficient mechanism for multimedia communications due to its high spectrum efficiency, which achieves point-to-multipoint transmission on the same radio resources. To satisfy the increasing demands for multimedia broadcast multicast service (MBMS), we present a power domain non-orthogonal MBMS transmission scheme in a K-tier heterogeneous network (HetNet). Firstly, the system model, usage scenarios, and fundamentals of the presented scheme are discussed. Next, a tractable framework is developed to analyse the performance of non-orthogonal MBMS transmission, by using stochastic geometry. Based on this framework, the analytical expressions for the signal-to-interference-plus-noise ratio (SINR) coverage probability, average number of served users, and sum rate are derived. Furthermore, synchronous non-orthogonal MBMS transmission to further improving the system performance is also studied. The results demonstrate that non-orthogonal MBMS transmission can achieve better performance than the conventional one, in which non-orthogonal multirate one can fully utilize channel conditions to achieve a significant rate gain, while non-orthogonal multi-service one can efficiently use power resources to guarantee the quality of service (QoS) of high priority users, and also provide services for low priority users simultaneously. Copyright © 2017, The Authors. All rights reserved.

关键词： Geometry

Enhanced random access and beam training for mmWave wireless local networks with high user density

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arXiv 2017年

作者： Zhou, Pei Fang, Xuming Fang, Yuguang Long, Yan He, Rong Han, Xiao Key Lab of Information Coding and Transmission Southwest Jiaotong University Chengdu610031 Department of Electrical and Computer Engineering University of Florida PO Box 116130 GainesvilleFL32611 United States Ct Lab Huawei Shenzhen518129

As low frequency band becomes more and more crowded, millimeter-wave (mmWave) has attracted significant attention recently. IEEE has released the 802.11ad standard to satisfy the demand of ultra-high-speed communication. It adopts beamforming technology that can generate directional beams to compensate for high path loss. In the Association Beamforming Training (A-BFT) phase of beamforming (BF) training, a station (STA) randomly selects an A-BFT slot to contend for training opportunity. Due to the limited number of A-BFT slots, A-BFT phase suffers high probability of collisions in dense user scenarios, resulting in inefficient training performance. Based on the evaluation of the IEEE 802.11ad standard and 802.11ay draft in dense user scenarios of mmWave wireless networks, we propose an enhanced A-BFT beam training and random access mechanism, including the Separated A-BFT (SA-BFT) and Secondary Backoff A-BFT (SBA-BFT). The SA-BFT can provide more A-BFT slots and divide A-BFT slots into two regions by defining a new 'E-A-BFT Length' field compared to the legacy 802.11ad A-BFT, thereby maintaining compatibility when 802.11ay devices are mixed with 802.11ad devices. It can also reduce the collision probability in dense user scenarios greatly. The SBA-BFT performs secondary backoff with very small overhead of transmission opportunities within one A-BFT slot, which not only further reduces collision probability, but also improves the A-BFT slots utilization. Furthermore, we propose a three-dimensional Markov model to analyze the performance of the SBA-BFT. The analytical and simulation results show that both the SA-BFT and the SBA-BFT can significantly improve BF training efficiency, which are beneficial to the optimization design of dense user wireless networks based on the IEEE 802.11ay standard and mmWave technology. Copyright © 2017, The Authors. All rights reserved.

关键词： Wireless local area networks (WLAN)

Beamspace SU-MIMO for future millimeter wave wireless communications

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arXiv 2017年

作者： Xue, Qing Fang, Xuming Wang, Cheng-Xiang Key Lab of Information Coding and Transmission Southwest Jiaotong University Chengdu610031 Institute of Sensors Signals and Systems School of Engineering and Physical Sciences Heriot-Watt University EdinburghEH14 4AS

For future networks (i.e., the fifth generation (5G) wireless networks and beyond), millimeter-wave (mmWave) communication with large availab.e unlicensed spectrum is a promising technology that enables gigabit multimedia applications. Thanks to the short wavelength of mmWave radio, massive antenna arrays can be packed into the limited dimensions of mmWave transceivers. Therefore, with directional beamforming (BF), both mmWave transmitters (MTXs) and mmWave receivers (MRXs) are capable of supporting multiple beams in 5G networks. However, for the transmission between an MTX and an MRX, most works have only considered a single beam, which means that they do not make full potential use of mmWave. Furthermore, the connectivity of single beam transmission can easily be blocked. In this context, we propose a single-user multi-beam concurrent transmission scheme for future mmWave networks with multiple reflected paths. Based on spatial spectrum reuse, the scheme can be described as a multiple-input multiple-output (MIMO) technique in beamspace (i.e., in the beam-number domain). Moreover, this study investigates the challenges and potential solutions for implementing this scheme, including multi-beam selection, cooperative beam tracking, multi-beam power allocation and synchronization. The theoretical and numerical results show that the proposed beamspace SU-MIMO can largely improve the achievable rate of the transmission between an MTX and an MRX and, meanwhile, can maintain the connectivity. Copyright © 2017, The Authors. All rights reserved.

关键词： Beamforming

A Novel Procedure to Model and Forecast Mobile Communication Traffic by ARIMA/GARCH Combination Models

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A Novel Procedure to Model and Forecast Mobile Communication...

2016 International Conference on Modeling, Simulation and Optimization Technologies and Applications（MSOTA 2016）

作者： Quang Thanh Tran Li Hao Quang Khai Trinh Key Lab of Information Coding and Transmission Southwest Jiaotong University

ISBN: (纸本)9781510835702

Mobile traffic modeling and forecasting are the key techniques in terms of network optimization and management because better network management can be achieved through improving the forecasting accuracy. While mobile traffic has been studied extensively and proved to be effectively modeled with ARIMA models, the volatility effect in mobile traffic series that results in forecasting errors was seldom mentioned. In this study, a multiplicative seasonal ARIMA/GARCH building procedure is proposed to show that volatility effect appearing in mobile traffic series can be processed by GARCH models. Our proposed procedure combines several evaluating parameters such as Akaike information Criterion(AIC), Schwarz Criterion(SIC), forecast performance evaluation information and residual correlogram to find out the most suitable model, based on which descriptive statistics are used to get the final choice. This work indicates that the mobile traffic series can be better modeled and forecasted by applying GARCH models based on a multiplicative seasonal ARIMA.

关键词： ARIMA GARCH GARCH-M traffic forecasting traffic modeling

An mmWave wireless communication and radar detection integrated network for railways

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An mmWave wireless communication and radar detection integra...

IEEE Vehicular Technology Conference

作者： Li Yan Xuming Fang Hengchao Li Chao Li Key Lab of Information Coding & Transmission Southwest Jiaotong University

ISBN: (纸本)9781509016990

With large availab.e continuous bandwidth, millimeter wave (mmWave) bands hold promise as a carrier frequency for fifth generation (5G) wireless communications. Moreover, mmWave bands also play an important role in radar detections. Based on this observation, we propose an mmWave wireless communication and radar detection integrated network architecture for railways, not only to increase the capacity of railway wireless communication systems, but also to realize train operation environment detection to enhance train operation safety. To overcome the aggravated path loss in mmWave bands, directional beamforming is generally used to concentrate signal radiation energy both in wireless communications and radar detections. Nevertheless, for wireless communications, the signaling blind zone of directional beamforming makes it less effective in wireless link establishment and maintenance. Therefore, in this proposed integrated network, two frequency bands are employed, where omnidirectionally radiated licensed lower frequency bands carry critical signaling and data, and mmWave bands are time-division multiplexed to transmit large-volume communication data for trains, or to perform environment detection for enhancing train operation safety. To mitigate handovers and to increase baseband processing resource utilization in railway scenarios, the proposed integrated network is deployed based on the cloud radio access network (C-RAN) architecture, where both licensed lower frequency band radio remote units (RRUs) and mmWave band RRUs are connected to a building baseband unit (BBU) pool through high-speed backhauls. Besides, physical (PHY) frame structures and up/downlink communication signaling procedures are designed for this proposed integrated network. Performance analysis results have demonstrated that the proposed integrated network can highly increase the capacity for railway wireless communication systems and achieve high distance and angular resolution for radar detect

关键词： MmWave 5G wireless communications Radar detections Railways Train operation safety railways CARRIER SYSTEM radar detection Integrated networks Rail transit Frequency bands Train operation Dead band Time division CARRIER FREQUENCY

SNR enhancement with bilateral filtering algorithm for phase-sensitive optical time domain reflectometry

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SNR enhancement with bilateral filtering algorithm for phase...

Asia-Pacific Optical Sensors Conference, APOS 2016

作者： He, Haijun Shao, Li-Yang Li, Hengchao Zhang, Zhiyong Luo, Bin Pan, Wei Yan, Lianshan Center for Information Photonics and Communications School of Information Science and Technology Southwest Jiaotong University Chengdu610031 China Key Lab of Information Coding and Transmission School of Information Science and Technology Southwest Jiaotong University Chengdu610031 China

A bilateral filtering algorithm has been proposed to process the phase-sensitive optical time domain reflectometry signal to enhance SNR. The maximum SNR enhancement of 8.3 dB has been achieved without spatial resolut... 详细信息

ISBN: (纸本)9780960038053

关键词： Reflection