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Joint user association and resource partition for downlink-uplink decoupling in multi-tier HetNets

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Frontiers of Information Technology & Electronic engineering 2017年第6期18卷 817-829页

作者： Zhi-yong FENG Ze-bing FENG T.Aaron GULLIVER MOE Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications Department of Electrical and Computer Engineering University of Victoria

Traditional cellular networks require the downlink (DL) and uplink (UL) of mobile users (MUs) to be associated with a single base station (BS). However, the power gap between BSs and MUs in different transmission environments results in the BS with the strongest downlink differing from the BS with the strongest uplink. In addition, the significant increase in the number of wireless machine type communication (MTC) devices accessing cellular networks has created a DL/UL traffic imbalance with higher traffic volume on the uplink. In this paper,a joint user association and resource partition framework for downlink-uplink decoupling (DUDe) is developed for a tiered heterogeneous cellular network (HCN). Different from the traditional association rules such as maximal received power and range extension, a coalition game based scheme is proposed for the optimal user association with DUDe. The stability and convergence of this scheme are proven and shown to converge to a Nash equilibrium at a geometric rate. Moreover, the DL and UL optimal bandwidth partition for BSs is derived based on user association considering fairness. Extensive simulation results demonstrate the effectiveness of the proposed scheme,which enhances the sum rate compared with other user association strategies.

关键词： Downlink-uplink decoupling User association Resource partition Heterogeneous cellular network Coalition game

Multi-Source Heterogeneous Core Data Acquisition Method in Edge Computing Nodes

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Multi-Source Heterogeneous Core Data Acquisition Method in E...

IEEE Annual International computer Software and Applications Conference (COMPSAC)

作者： Hong Xia Mingdao Zhao Yanping Chen Zhongmin Wang Zhong Yu Jingwei Yang School of Computer Science Xi’an University of Posts and Telecommunications Shaanxi Key Laboratory of Network Data Analysis and Intelligent Processing Xi’an University of Posts and Telecommunications Xi’an China School of Computer Science Xi’an University of Posts and Telecommunications Xi’an China School of Communications and Information Engineering Xi’an University of Posts and Telecommunication Xi’an China Department of Computer Science California State University Sacramento United State

As the volume of data grows exponentially, big data brings an unprecedented burden to the current computing infrastructure. How to deal with big data efficiently and concisely and reduce the burden of computing infrastructure has always been a big challenge. Therefore, this paper proposes a high-quality core data extraction method in edge computing nodes. Firstly, heterogeneous data are fused into a unified model, the data characteristics of the original data are retained. Then, a Lanzcos-based incremental tensor decomposition method is proposed to extracted the high quality core tensor dynamically. Finally, the model algorithm is verified using real data. The experimental results show that the approximate tensor reconstructed from the tensor containing 15% of the core data can guarantee 90% accuracy. At the same time, IncLHOSVD is significantly better than non-incremental HOSVD in execution time in guaranteeing the accuracy of approximate equal error.

关键词： Edge computing Internet of Things Data mining Matrix decomposition Computational modeling Data models

On the performance of particle filters with adaptive number of particles

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arXiv 2019年

作者： Elvira, Víctor Miguez, Joaquín Djurić, Petar M. School of Mathematics University of Edinburgh United Kingdom Department of Signal Theory & Communications Universidad Carlos III de Madrid Spain IIS Gregorio Marañón Spain Department of Electrical and Computer Engineering Stony Brook University United States

We investigate the performance of a class of particle filters (PFs) that can automatically tune their computational complexity by evaluating online certain predictive statistics which are invariant for a broad class of state-space models. To be specific, we propose a family of block-adaptive PFs based on the methodology of Elvira et al (2017). In this class of algorithms, the number of Monte Carlo samples (known as particles) is adjusted periodically, and we prove that the theoretical error bounds of the PF actually adapt to the updates in the number of particles. The evaluation of the predictive statistics that lies at the core of the methodology is done by generating fictitious observations, i.e., particles in the observation space. We study, both analytically and numerically, the impact of the number K of these particles on the performance of the algorithm. In particular, we prove that if the predictive statistics with K fictitious observations converged exactly, then the particle approximation of the filtering distribution would match the first K elements in a series of moments of the true filter. This result can be understood as a converse to some convergence theorems for PFs. From this analysis, we deduce an alternative predictive statistic that can be computed (for some models) without sampling any fictitious observations at all. Finally, we conduct an extensive simulation study that illustrates the theoretical results and provides further insights into the complexity, performance and behavior of the new class of algorithms. Copyright © 2019, The Authors. All rights reserved.

关键词： Monte Carlo methods

Through-body Communication Measurements Using Wearable and Implantable Sensor Antennas

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Through-body Communication Measurements Using Wearable and I...

Antennas Design and Measurement International Conference (ADMInC)

作者： Abdul Quddious Photos Vryonides Symeon Nikolaou Marco A. Antoniades Muhammad Ali Babar Abbasi Frederick Research Center Frederick University Nicosia Cyprus Department of Electrical and Computer Engineering University of Cyprus Nicosia Cyprus Institute of Electronics Communications and Information Technology (ECIT) Queen’s University Belfast Belfast UK

ISBN: (纸本)9781728136004

This manuscript presents a successful through-body communication test bench using a customized wearable sensor antenna and an implantable sensor antenna. The sensor antennas were directly connected with VNA cables and two-port S-parameter measurements were conducted. The measurements verified the complex simulation setup that allows accurate modeling for the surrounding environment of implantable and wearable sensors. The simulation model verification was accomplished through the direct comparison of the simulation setup with the measurement setup. The measurement setup with a cable-connected implantable sensor was made possible through the placement of the implantable sensor under the armpit of a human subject. For the feasibility of the S-parameter measurements, two novel sensor antennas were implemented and used. A very compact, implantable sensor antenna, and a bi-directional wearable sensor loaded with two back-to-back antennas, designed and optimized to radiate effectively towards the human body and away from the human body, respectively.

关键词： Antennas Antenna measurements Wearable sensors Numerical models Biomedical monitoring Phantoms

Channel estimation and hybrid precoding for distributed phased arrays based MIMO wireless communications

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arXiv 2019年

作者： Zhang, Yu Huo, Yiming Wang, Dongming Dong, Xiaodai You, Xiaohu National Mobile Communications Research Laboratory Southeast University Nanjing210096 China Department of Electrical and Computer Engineering University of Victoria VictoriaBCV8P 5C2 Canada

Distributed phased arrays based multiple-input multiple-output (DPA-MIMO) is a newly debuted architecture that enables both spatial multiplexing and beamforming while facilitating highly reconfigurable hardware implementation in millimeter-wave (mmWave) frequency bands. With a DPA-MIMO system, we focus on channel state information (CSI) acquisition and hybrid precoding. As benefited from a coordinated and open-loop pilot beam pattern design, all the subarrays can simultaneously perform channel sounding with less training overhead compared to the time-sharing operation of each subarray. Furthermore, two sparse channel recovery algorithms, known as joint orthogonal matching pursuit (JOMP) and joint sparse Bayesian learning with 2 reweighting (JSBL-2), are proposed to exploit the hidden structured sparsity in the beam-domain channel vector. Finally, successive interference cancellation (SIC) based hybrid precoding through subarray grouping is illustrated for the DPA-MIMO system, which decomposes the joint subarray RF beamformer design into an interactive per-subarray-group handle. Simulation results show that the proposed two channel estimators fully take advantage of the partial coupling characteristic of DPA-MIMO channels to perform channel recovery, and the proposed hybrid precoding algorithm is suitable for such array-of-subarrays architecture with satisfactory performance and low complexity. Copyright © 2019, The Authors. All rights reserved.

关键词： MIMO systems

ADMM enabled hybrid precoding in wideband distributed phased arrays based mimo systems

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arXiv 2019年

作者： Zhang, Yu Huo, Yiming Zhan, Jinlong Wang, Dongming Dong, Xiaodai You, Xiaohu National Mobile Communications Research Laboratory Southeast University Nanjing210096 China Department of Electrical and Computer Engineering University of Victoria VictoriaBCV8W 3P6 Canada

Distributed phased arrays based multiple-input multiple-output (DPA-MIMO) is a recently proposed highly reconfigurable architecture enabling both spatial multiplexing and beamforming in millimeter-wave (mmWave) systems. In this work, we focus on coping with the hybrid precoding for the wideband DPA-MIMO system with orthogonal frequency division multiplexing (OFDM) modulation. More specifically, we propose an alternating direction method of multipliers (ADMM) enabled hybrid precoding approach based on an alternating optimization framework, abbreviated to ADMM-AltMin, for such cooperative array-of-subarrays structures. Simulation results show that the proposed ADMM-AltMin method achieves favourable performance with practical quantization of phase shifters taken into account. Copyright © 2019, The Authors. All rights reserved.

关键词： Millimeter waves

PROVenance Patterns in Numerical Modelling and Finite Element Simulation Processes of Bio-electric Systems*

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PROVenance Patterns in Numerical Modelling and Finite Elemen...

Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： Max Schröder Hendrikje Raben Frank Krüger Andreas Ruscheinski Ursula van Rienen Adelinde Uhrmacher Sascha Spors University Library University of Rostock Germany Institute of General Electrical Engineering University of Rostock Germany Institute of Communications Engineering University of Rostock Germany Institute of Computer Science University of Rostock Germany Department Life Light & Matter University of Rostock Germany

The reproducibility of scientific results gains increasing attention. In the context of biomedical engineering, this applies to experimental studies of three different kinds: in-vivo, in-vitro, and in-silico. Numerical modelling and finite element simulation of bio-electric systems are intricate processes involving manifold steps. A typical example of this process is the electrical stimulation at alloplastic reconstruction plates of the mandible. During the bio-electric modelling and simulation process, diverse methods realised in various software tools are exploited. To comprehensibly render how the final model has been developed requires a thorough documentation. We exploit the W3C provenance model PROV to structure this process and to make it accessible for modellers and for automatic analyses. Different entity types, such as data, model, software, literature, assumptions, and mathematical equations are distinguished; roles of entities within an activity are revealed as well as the involved researchers. In addition, we identify five process patterns: 1) information extraction from the literature; 2) generation of a geometrical model which uses data as input; 3) composition of several geometrical or mathematical models into a combined model; 4) parameterisation, which augments the input model by additional properties; and, finally, 5) refinement, which uses a model in addition to an assumption and generates an enhanced model. By modelling provenance information of a typical bio-electric modelling and simulation process as well as identifying provenance patterns, we provide a first step towards a better documentation of academic investigations in that scientific field.

关键词： Mathematical model Biological system modeling Data models Computational modeling Solid modeling Numerical models Software

Wireless traffic prediction with scalable gaussian process: Framework, algorithms, and verification

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arXiv 2019年

作者： Xu, Yue Yin, Feng Xu, Wenjun Lin, Jiaru Cui, Shuguang Key Lab of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications SRIBD Chinese University of Hong Kong Shenzhen China Department of Electrical and Computer Engineering University of California Davis United States

The cloud radio access network (C-RAN) is a promising paradigm to meet the stringent requirements of the fifth generation (5G) wireless systems. Meanwhile, wireless traffic prediction is a key enabler for C-RANs to improve both the spectrum efficiency and energy efficiency through load-aware network managements. This paper proposes a scalable Gaussian process (GP) framework as a promising solution to achieve large-scale wireless traffic prediction in a cost-efficient manner. Our contribution is three-fold. First, to the best of our knowledge, this paper is the first to empower GP regression with the alternating direction method of multipliers (ADMM) for parallel hyper-parameter optimization in the training phase, where such a scalable training framework well balances the local estimation in baseband units (BBUs) and information consensus among BBUs in a principled way for large-scale executions. Second, in the prediction phase, we fuse local predictions obtained from the BBUs via a cross-validation based optimal strategy, which demonstrates itself to be reliable and robust for general regression tasks. Moreover, such a cross-validation based optimal fusion strategy is built upon a well acknowledged probabilistic model to retain the valuable closed-form GP inference properties. Third, we propose a C-RAN based scalable wireless prediction architecture, where the prediction accuracy and the time consumption can be balanced by tuning the number of the BBUs according to the real-time system demands. Experimental results show that our proposed scalable GP model can outperform the state-of-the-art approaches considerably, in terms of wireless traffic prediction performance. Copyright © 2019, The Authors. All rights reserved.

关键词： Forecasting

Propagation and UWB Channel Characteristics on the Human Abdomen Area

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Propagation and UWB Channel Characteristics on the Human Abd...

European Conference on Antennas and Propagation, EuCAP

作者： Mariella Särestöniemi Chaïmaâ Kissi Carlos Pomalaza Raez Marko Sonkki Matti Hämäläinen Jari Iinatti Centre for Wireless Communications University of Oulu Finland Electronics and Telecommunication Systems Research Group National School of Applied Sciences (ENSA) Ibn TofailUniversity Kenitra Morocco Department of Electrical and Computer Engineering Purdue University USA

In this paper, radio channel characteristics and signal propagation on the human abdomen area, in particular small intestine part, are evaluated by simulations. Studies are based on a recently published low ultra wideband cavity-backed antenna designed for in-body communications. The study is carried out with finite integration technique based electromagnetic propagation simulations. The main target of this study is to evaluate different antenna locations and antenna distances for the context of the wireless capsule endoscope localization. The study is carried out by evaluating frequency and time domain responses, as well as studying the strength of the E-fields and power inside the small intestine by introducing monitor points with different antenna location options. Furthermore, 2D power flow figures are used as to get insight to the power flow and to the propagation, in general, within the tissues. It is shown that channel characteristics and power flow vary significantly with frequency as well as with different antenna locations.

关键词： Abdomen Load flow Intestines Monitoring Wireless communication Ultra wideband antennas