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IEEE International Conference on Electronic Information and Communication Technology (ICEICT)

作者： YaQi Liu Botao Feng Li Deng College of Electronics and Information Engineering Shenzhen University Shenzhen China Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China

ISBN: (数字)9781728190457

ISBN: (纸本)9781728190464

An omni-directional broad-band microstrip array antenna is proposed in this work. The serial feed and antenna array technology are combined to design an antenna array which can satisfy the demands of both omni-directionality in H-plane and high gain. The radiating patches are printed on dual sides of a printed circuit board (PCB) with an overall size of 128 mm × 7.5 mm × 1 mm. An operating bandwidth of 1975 MHz (5.15-7.125 GHz) is achieved, which is suitable for WiFi-6 wireless communication systems.

关键词： Wireless communication Microstrip antenna arrays Printed circuits Microstrip antennas Antenna feeds Information and communication technology Microstrip

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A Compact Dual-Polarized Differentially-Fed Antenna with High Gain for 5G Microcells

A Compact Dual-Polarized Differentially-Fed Antenna with Hig...

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IEEE International Conference on Electronic Information and Communication Technology (ICEICT)

作者： Haoming Li Wenhua Cao Botao Feng Li Deng College of Electronics and Information Engineering Shenzhen University Shenzhen China Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China

ISBN: (数字)9781728190457

ISBN: (纸本)9781728190464

A compact dual-polarized differentially-fed antenna with high gain is proposed for 5G microcells. The antenna mainly consists of two parts: a radiating element with metasurface and a differentially-fed network. The metasurface with four square cells is etched on the top layer, while the radiating octagonal patch etched with four fan-shaped slots is placed on the second layer. The profile of the antenna is 0.125 λ 0 (where λ 0 is the starting wavelength). Simulation results show that the overlapped bandwidths are 3.30-3.61 GHz and 4.72-5.07 GHz, and their corresponding gains vary from 8.30 to 9.65 dBi.

关键词： 5G mobile communication Simulation Conferences Microcell networks Metasurfaces Information and communication technology Antennas

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A Novel Omni-directional Antenna with Low Gain Variations for WiFi Communications

A Novel Omni-directional Antenna with Low Gain Variations fo...

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IEEE International Conference on Electronic Information and Communication Technology (ICEICT)

作者： Wucai Deng Botao Feng Li Deng College of Electronics and Information Engineering Shenzhen University Shenzhen China Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China

ISBN: (数字)9781728190457

ISBN: (纸本)9781728190464

An omni-directional monopole antenna with low gain variations is presented for Wireless Fidelity (WiFi) communications in this paper. Compared with the conventional microstrip antenna, the novel patch antenna with simple structure shows good performance in the aspects of high gain and low gain variations. Within ±1dB gain variations, dual bandwidths of 2.41GHz-2.57 GHz (6.4%) and 2.87 GHz-3.77 GHz (27.1%) are achieved for WIFI communication systems. To acquire the dual-band and omni-directional characteristics, the rectangular patch etched with an annular-ring slot is employed. Owing to the coplanar waveguide (CPW) feeding structure, the proposed antenna has an excellent performance of a stable gain of 2±0.5 dBi.

关键词： Patch antennas Dual band Microstrip antennas Coplanar waveguides Information and communication technology Microstrip Wireless fidelity

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A Dual-Polarized Omnidirectional Antenna with High Isolation for 2G/3G/LTE/5G Scenarios

A Dual-Polarized Omnidirectional Antenna with High Isolation...

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IEEE International Conference on Electronic Information and Communication Technology (ICEICT)

ISBN: (数字)9781728190457

ISBN: (纸本)9781728190464

This paper presents a dual polarized omnidirectional antenna with high isolation for 3G/LTE/5G scenarios. The antenna is comprised of two parts: a vertically polarized radiating element composed of 3 copper patches and a horizontally polarized radiating element composed of 4 printed dipoles and a four-way power divider. The overall profile height of the antenna is 0.3 λ 0 (where λ 0 is the starting wavelength). Simulation results show that the overlapped bandwidth between horizontal polarization (HP) and vertical polarization (VP) is 1.66-3.65 GHz, and the isolation is less than -42 dB. Moreover, low gain variations within 3 dB in both VP and HP directions can also be attained, which means good omni-directional characteristics.

关键词： Power dividers Dipole antennas Simulation Omnidirectional antennas Information and communication technology Copper Gain

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Optimization of User Selection and Bandwidth Allocation for Federated Learning in VLC/RF systems

Optimization of User Selection and Bandwidth Allocation for ...

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IEEE Conference on Wireless Communications and networking

作者： Chuanhong Liu Caili Guo Yang Yang Mingzhe Chen H. Vincent Poor Shuguang Cui Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing China Beijing Laboratory of Advanced Information Networks School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing China Princeton University Princeton NJ USA The Future Network of Intelligence Institute The Chinese University of Hong Kong Shenzhen China Shenzhen Research Institute of Big Data The Chinese University of Hong Kong Shenzhen China

ISBN: (纸本)9781728195056;9781728195063

Limited radio frequency (RF) resources restrict the number of users that can participate in federated learning (FL) thus affecting FL convergence speed and performance. In this paper, we first introduce visible light communication (VLC) as a supplement to RF in FL and build a hybrid VLC/RF communication system, in which each indoor user can use both VLC and RF to transmit its FL model parameters. Then, the problem of user selection and bandwidth allocation is studied for FL implemented over a hybrid VLC/RF system aiming to optimize the FL performance. The problem is first separated into two subproblems. The first subproblem is a user selection problem with a given bandwidth allocation, which is solved by a traversal algorithm. The second subproblem is a bandwidth allocation problem with a given user selection, which is solved by a numerical method. The final user selection and bandwidth allocation are obtained by iteratively solving these two subproblems. Simulation results show that the proposed FL algorithm that efficiently uses VLC and RF for FL model transmission can improve the prediction accuracy by up to 10% compared with a conventional FL system using only RF.

关键词： Radio frequency Training Simulation Bandwidth Channel allocation Predictive models Collaborative work

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Uav trajectory and communication co-design: flexible path discretization and path compression

arXiv

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arXiv 2020年

作者： Guo, Yijun You, Changsheng Yin, Changchuan Zhang, Rui Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications China Department of Electrical and Computer Engineering National University of Singapore Singapore

The performance optimization of UAV communication systems requires the joint design of UAV trajectory and communication efficiently. To tackle the challenge of infinite design variables arising from the continuous-time UAV trajectory optimization, a commonly adopted approach in the existing literature is by approximating the UAV trajectory with piecewise-linear path segments connected via a finite number of waypoints in three-dimensional (3D) space. However, this approach may still incur prohibitive computational complexity in practice when the UAV flight period/distance becomes long, as the distance between consecutive waypoints needs to be kept sufficiently small to retain high approximation accuracy. To resolve this fundamental issue, we propose in this paper a new and general framework for UAV trajectory and communication co-design with flexible number of waypoint optimization variables (called designable waypoints) or their sub-path representations. First, we propose a flexible path discretization scheme that optimizes only a number of selected waypoints (designable waypoints) along the UAV path for complexity reduction, while all the designable and non-designable waypoints are used in calculating the approximated communication utility along the UAV trajectory for ensuring high trajectory discretization accuracy. Next, given any number of designable waypoints, we propose a novel path compression scheme where the UAV 3D path is first decomposed into three one-dimensional (1D) sub-paths and each sub-path is then approximated by superimposing a number of selected basis paths (which are generally less than the number of designable waypoints) weighted by their corresponding path coefficients, thus further reducing the path design complexity. Finally, we provide a case study on UAV trajectory design for aerial data harvesting from distributed ground sensors, and numerically show that the proposed flexible path discretization and path compression schemes can significa

关键词： Unmanned aerial vehicles (UAV)

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Hypergraph-Coloring-Based Pilot Allocation Algorithm for Massive MIMO systems

Hypergraph-Coloring-Based Pilot Allocation Algorithm for Mas...

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International Conference on Communications, Signal Processing, and systems, CSPS 2018

作者： Lian, Yongjin Zhang, Tiankui Wang, Youxiang Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing100876 China China Unicom Network Technology Research Institution Beijing China

ISBN: (纸本)9789811362637

Pilot contamination caused by unavoidable reuse of pilots in adjacent cell limits the performance of the massive multiple-input multiple-output (MIMO) systems severely. In this paper, we propose a hypergraph-coloring-based pilot allocation (HCPA) algorithm for pilot contamination mitigation, which can improve the system sum rate with the minimum achievable data rate requirement. In the proposed algorithm, an interference relationship graph with hyperedges to restrict the minimum uplink achievable rate is established, and then the pilots are allocated by graph coloring method. The numerical results show that the proposed algorithm can improve both the minimum achievable data rate and the total uplink sum rate. © 2019, Springer Nature Singapore Pte Ltd.

关键词： MIMO systems

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Use OFDM In OAM Communication to Redcuce Multi-path Effects

Use OFDM In OAM Communication to Redcuce Multi-path Effects

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IEEE International Conference on Electronic Information and Communication Technology (ICEICT)

作者： Jingyue Shu Li Deng Shufang Li Botao Feng Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture Convergence Beijing University of Posts and Telecommunications Beijing China College of Electronics and Information Engineering Shenzhen University Shenzhen China

ISBN: (数字)9781728190457

ISBN: (纸本)9781728190464

The orbital angular momentum (OAM) has raised great attention for its potential to enhance the capacity of wireless communication system. The performance of OAM communication is dependent on the accuracy of phase information. In multi-path channel, the accuracy is destroyed. In this paper, we use orthogonal frequency division multiplexing (OFDM)before OAM modulation to enhance communication performance.

关键词： Wireless communication OFDM Conferences Modulation Orbits Information and communication technology

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Adaptive Information Bottleneck Guided Joint Source and Channel Coding for Image Transmission

arXiv

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arXiv 2022年

作者： Sun, Lunan Yang, Yang Chen, Mingzhe Guo, Caili Saad, Walid Poor, H. Vincent The Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing100876 China The Department of Electrical and Computer Engineering Institute for Data Science and Computing University of Miami Coral GablesFL33146 United States The Beijing Laboratory of Advanced Information Net works School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing100876 China The Wireless@VT Group Bradley Department of Electrical and Computer Engineering Virginia Tech ArlingtonVA United States The Department of Electrical and Computer Engineering Princeton University PrincetonNJ08544 United States

Joint source and channel coding (JSCC) for image transmission has attracted increasing attention due to its robustness and high efficiency. However, the existing deep JSCC research mainly focuses on minimizing the distortion between the transmitted and received information under a fixed number of available channels. Therefore, the transmitted rate may be far more than its required minimum value. In this paper, an adaptive information bottleneck (IB) guided joint source and channel coding (AIB-JSCC) method is proposed for image transmission. The goal of AIB-JSCC is to reduce the transmission rate while improving the image reconstruction quality. In particular, a new IB objective for image transmission is proposed so as to minimize the distortion and the transmission rate. A mathematically tractable lower bound on the proposed objective is derived, and then, adopted as the loss function of AIB-JSCC. To trade off compression and reconstruction quality, an adaptive algorithm is proposed to adjust the hyperparameter of the proposed loss function dynamically according to the distortion during the training. Experimental results show that AIB-JSCC can significantly reduce the required amount of transmitted data and improve the reconstruction quality and downstream task accuracy. Copyright © 2022, The Authors. All rights reserved.

关键词： Economic and social effects

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Highly Efficient Generation of Non-diffraction Bessel Beams with Metasurface

Highly Efficient Generation of Non-diffraction Bessel Beams ...

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IEEE International Conference on Electronic Information and Communication Technology (ICEICT)

作者： Ting Zeng Li Deng Shufang Li Botao Feng Beijing Laboratory of Advanced Information Networks & Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China College of Electronics and Information Engineering Shenzhen University Shenzhen China

ISBN: (数字)9781728190457

ISBN: (纸本)9781728190464

A reflection metasurface that can generate non-diffraction Bessel beams and achieve anomalous reflection with high efficiency at 5.8 GHz is proposed in this paper. The unit it utilizes has excellent amplitude and phase characteristics, greatly facilitating the construction of the proposed metasurface and laying a solid foundation for the improvement of efficiency. According to non-diffraction theory and anomalous reflection law, two metasurfaces are designed for comparison. The simulation results show that the designed metasurfaces successfully realize the non-diffractive beam with a focusing distance of 126 mm (2.44 λ 0 ), and can bend the normally reflected wave to the direction 10° from the +z direction in a vertical plane 45° away from the +x direction. The average efficiency of the metasurface within the focusing range is as high as 84.5%, thus could be used as radio energy transmission, telecommunication multiplexing and accurate detection devices.

关键词： Multiplexing system dynamics Focusing Metasurfaces Solids Reflection Structural beams

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