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The performance of circularly polarized phased sub-array antennas for 5G laptop devices investigating the radiation effects

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Progress in Electromagnetics Research C 2021年 110卷 267-283页

作者： Mahmoud, Korany R. Baz, Abdullah Alhakami, Wajdi Alhakami, Hosam Montaser, Ahmed M. Department of Electronics and Communications Faculty of Engineering Helwan University Cairo Egypt National Telecommunications Regulatory Authority Ministry of Communication and Information Technology Giza Egypt Computer Engineering Department College of Computer and Information Systems Umm Al-Qura University Makkah Saudi Arabia Department of Computer Science College of Computer and Information Technology Taif University P. O. Box 11099 Taif21944 Saudi Arabia Department of Computer Science College of Computer and Information Techonogy Umm Al-Qura University Makkah21955 Saudi Arabia Electrical Engineering Department Sohag University Sohag Egypt

In this paper, the performance of circularly polarized (CP) adaptive sub-arrays integrated into 5G laptop device is investigated in the presence of a whole-body human phantom model. In addition, the radiation effect of the steered beam patterns has been analyzed by calculating the specific absorption rate distribution and temperature rise. In this target, a single-feed CP antenna element has been firstly designed to resonate at 28GHz with high realized gain and radiation efficiency. Then, 4 subarrays have been constructed in a rectangular configuration with four-elements for each sub-array. To let the study more realistic, a complete human model is considered to investigate the radiation effects. The measured reflection coefficient and realized gain results of the designed antenna element are found to be -30 dB and 7.82 dB, respectively, in the assigned frequency band. Likewise, the antennas sub-arrays have approximately kept the same impedance matching attitude with high insertion loss of -22 dB and a realized gain and radiation efficiency of 16.85 dB and 86%, respectively, on average. Furthermore, the sub-arrays scan patterns and coverage efficiency have been studied considering the existence of the human body in different scenarios. Regarding the RF exposure, the results show that the resultant maximum values of specific absorption rate and power density do not exceed 1.52 W/kg and 3.5W/m2, respectively, whereas the maximum exposure temperature in such a case is less than 2.8°C after 30 minutes and decreases to 0.5°C after a penetration depth of 3mm which reflects the possibility of safe use. © 2021, Electromagnetics Academy. All rights reserved.

关键词： Radiation efficiency

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Multiband Patch Antenna Design Using Nature-Inspired Optimization Method

IEEE Open Journal of Antennas and Propagation

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IEEE Open Journal of Antennas and Propagation 2021年 2卷 151-162页

作者： Boursianis, Achilles D. Papadopoulou, Maria S. Pierezan, Juliano Mariani, Viviana C. Coelho, Leandro S. Sarigiannidis, Panagiotis Koulouridis, Stavros Goudos, Sotirios K. ELEDIA@AUTH Research Group School of Physics Aristotle University of Thessaloniki Thessaloniki54124 Greece Department of Electrical Engineering Federal University of Parana Curitiba80060-000 Brazil Industrial and Systems Engineering Graduate Program and Mechanical Engineering Graduate Program Pontifical Catholic University of Parana Curitiba80215-901 Brazil Department of Electrical and Computer Engineering University of Western Macedonia Kozani501 00 Greece Electrical and Computer Engineering Department University of Patras Patras26504 Greece

Radio frequency energy harvesting has attracted considerable interest as a technique of enabling self-powered wireless networks. This technique faces several challenges, such as the receiving and the rectifying modules of a rectenna system. Multiband antennas provide several comparative advantages against the goal of maximizing the amount of energy harvesting. In this work, we present a multiband microstrip patch antenna with three slits operating in the LoRaWAN (Long Range Wide Area Network) and the cellular (GSM-1800 and UMTS) communication frequency bands. A feasible solution of the antenna is obtained by the application of a recently introduced nature-inspired optimization technique, namely the Coyote Optimization Algorithm. The proposed antenna operates satisfactorily in the LoRaWAN (Long Range Wide Area Network) and the cellular (GSM-1800 and UMTS) communication frequency bands. Measured results of the proposed antenna exhibit an acceptable performance (multiband frequency operation, maximum gain of 3.94 dBi, broadside operation) and demonstrate features of operation, which make it a strong candidate for various RF energy harvesting applications. © 2020 IEEE.

关键词： Microstrip antennas

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ByteStack-ID: Integrated Stacked Model Leveraging Payload Byte Frequency for Grayscale Image-based Network Intrusion Detection

ByteStack-ID: Integrated Stacked Model Leveraging Payload By...

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IEEE International Conference on Communications (ICC)

作者： Irfan Khan Yasir Ali Farrukh Syed Wali Department of Marine Engineering Technology in joint appointment with Electrical and Computer Engineering Department and Computer Science & Engineering Department Texas A&M University Galveston TX USA Clean and Resilient Energy Systems (CARES) Lab Texas A&M University College Station TX USA

ISBN: (数字)9781728190549

ISBN: (纸本)9781728190556

In the ever-evolving realm of network security, the swift and accurate identification of diverse attack classes within network traffic is of paramount importance. This paper introduces “ByteStack-ID,” a pioneering approach tailored for packet-level intrusion detection. At its core, ByteStack-ID leverages grayscale images generated from the frequency distributions of payload data, a groundbreaking technique that greatly enhances the model's ability to discern intricate data patterns. Notably, our approach is exclusively grounded in packet-level information, a departure from conventional Network Intrusion Detection systems (NIDS) that predominantly rely on flow-based data. While building upon the fundamental concept of stacking methodology, ByteStack-ID diverges from traditional stacking approaches. It seamlessly integrates additional meta learner layers into the concatenated base learners, creating a highly optimized, unified model. Empirical results unequivocally confirm the outstanding effectiveness of the ByteStack-ID framework, consistently outperforming baseline models and state-of-the-art approaches across pivotal performance metrics, including precision, recall, and F1-score. Impressively, our proposed approach achieves an exceptional 81% macro F1-score in multiclass classification tasks. In a landscape marked by the continuous evolution of network threats, ByteStack-ID emerges as a robust and versatile security solution, relying solely on packet-level information extracted from network traffic data.

关键词： Measurement Technological innovation Stacking Network intrusion detection Telecommunication traffic Gray-scale Network security

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One-Shot Localization with Random Wavefronts 30

One-Shot Localization with Random Wavefronts

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30th International Conference on Mobile Computing and Networking, ACM MobiCom 2024

作者： Bilgin, Burak Liao, Jy-Chin Chen, Hou-Tong Chang, Chun-Chieh Addamane, Sadhvikas Lilly, Michael P. Mittleman, Daniel M. Knightly, Edward W. Department of Electrical and Computer Engineering Rice University HoustonTX United States Center for Integrated Nanotechnologies Los Alamos National Laboratory Los AlamosNM United States Center for Integrated Nanotechnologies Sandia National Laboratories AlbuquerqueNM United States School of Engineering Brown University ProvidenceRI United States

ISBN: (纸本)9798400704895

The next generation of wireless networks will utilize highly directional beams to overcome the path loss at high frequencies, requiring angle inference during link establishment. Furthermore, the integration of location-based services into the wireless infrastructure is rapidly increasing, bringing in a significant demand for an integrated fast localization scheme. In this work, we present a first-of-its-kind one-shot angular localization method that is carried out with a re-configurable architecture that unlocks ISAC functionality. Specifically, we use an electrically tunable metasurface with broadband response to generate wavefronts that are randomized across the angular space with diverse wideband amplitude and phase observations, corresponding to a collection of angle-unique one-shot beacons. Our results show down to 0.26° mean absolute error at 20 dB SNR, an order of magnitude improvement over the recently proposed one-shot solutions based on leaky-wave antennas (LWAs), in addition to having wider area coverage and less stringent bandwidth requirements. © 2024 Copyright is held by the owner/author(s). Publication rights licensed to ACM.

关键词： Location based services

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A Fast CU Partitioning Algorithm Based on Texture Characteristics for VVC 23

A Fast CU Partitioning Algorithm Based on Texture Characteri...

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5th International Conference on Image Processing and Machine Vision, IPMV 2023

作者： Li, Wei Jiang, Xiantao Jin, Jiayuan Song, Tian Yu, Fei Richard Department of Information Engineering Shanghai Maritime University NO.1550 Haigang Ave. Shanghai201306 China Department of Electrical and Electronics Engineering Tokushima University 2-24 Shinkura-cho Tokushima770-8501 Japan Department of Systems and Computer Engineering Carleton University OttawaONK1S 5B6 Canada

ISBN: (纸本)9781450397926

Different from the traditional quaternary tree (QT) structure utilized in the previous generation video coding standard H.265/HEVC, a new partition structure named quadtree with nested multi-type tree (QTMT) is applied in the latest codec H.266/VVC. The introduction of QTMT brings in superior encoding performance at the cost of great time-consuming. Therefore, this paper proposes a fast coding unit (CU) partitioning algorithm based on CU texture complexity and texture direction. First, we terminate further splitting of a CU when its texture is judged as simple. Then, we use the gray level co-occurrence matrix (GLCM) to extract the texture direction of the block to decide whether to partition this CU by QT, thus terminating further MT partitions. Finally, a final partition type is selected from the four MT partitions in combination with the multi-level texture complexity and texture direction of the block. The simulation results show that the overall algorithm can significantly reduce the encoding time, while the loss of coding efficiency is reasonably low. In comparison with the reference model, the encoding time is reduced by up to 44.71%, while the BDBR is increased by only 0.84% on average. © 2023 ACM.

关键词： Encoding (symbols)

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Transient states to control the electromagnetic response of space-time dispersive media

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Physical Review B 2024年第23期110卷 235125-235125页

作者： Pablo H. Zapata-Cano Salvador Moreno-Rodríguez Stamatios Amanatiadis Antonio Alex-Amor Zaharias D. Zaharis Carlos Molero School of Electrical and Computer Engineering Aristotle University of Thessaloniki 54124 Thessaloniki Greece Department of Signal Theory Telematics and Communications Research Centre for Information and Communication Technologies (CITIC-UGR) Universidad de Granada 18071 Granada Spain Department of Electrical and Systems Engineering University of Pennsylvania Philadelphia Pennsylvania 19104 USA

In this paper, we study the dynamic formation of transients when plane waves impinge on a dispersive slab that abruptly changes its electrical properties in time. The time-varying slab alternates between air and metal-like states, whose frequency dispersion is described by the Drude model. It is shown how the physics of this complex system can be well described with the joint combination of two terms: one associated with temporal refractions and the other associated with spatial refractions. To test the validity of the approach, some analytical results are compared with a self-implemented finite-difference time-domain method. Results show how the transients that occur after the abrupt temporal changes can shape the overall steady-state response of the space-time system. In fact, far from always being detrimental, these transient states can be conveniently used to perform frequency conversion or to amplify or attenuate the electromagnetic fields.

关键词： Electromagnetic transients

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FORS-EMG: A Novel sEMG Dataset for Hand Gesture Recognition Across Multiple Forearm Orientations

arXiv

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arXiv 2024年

作者： Rumman, Umme Ferdousi, Arifa Saha, Bipin Hossain, Md. Sazzad Islam, Md. Johirul Ahmad, Shamim Reaz, Mamun Bin Ibne Islam, Md. Rezaul The Department of Computer Science and Engineering Varendra University Rajshahi Bangladesh The Department of Electrical Electronic and Systems Engineering Universiti Kebangsaan Malaysia Selangor Bangi Malaysia The Department of Physics Rajshahi University of Engineering and Technology Rajshahi6204 Bangladesh The Department of Electrical and Electronic Engineering University of Rajshahi Rajshahi6205 Bangladesh The Department of Computer Science and Engineering University of Rajshahi Rajshahi6205 Bangladesh The Department of Electrical and Electronic Engineering Independent University Dhaka Bangladesh

Surface electromyography (sEMG) signals hold significant potential for gesture recognition and robust prosthetic hand development. However, sEMG signals are affected by various physiological and dynamic factors, including forearm orientation, electrode displacement, and limb position. Most existing sEMG datasets lack these dynamic considerations. This study introduces a novel multichannel sEMG dataset to evaluate commonly used hand gestures across three distinct forearm orientations. The dataset was collected from nineteen able-bodied subjects performing twelve hand gestures in three forearm orientations-supination, rest, and pronation. Eight MFI EMG electrodes were strategically placed at the elbow and mid-forearm to record high-quality EMG signals. Signal quality was validated through Signal-to-Noise Ratio (SNR) and Signal-to-Motion artifact Ratio (SMR) metrics. Hand gesture classification performance across forearm orientations was evaluated using machine learning classifiers, including LDA, SVM, and KNN, alongside five feature extraction methods: TDD, TSD, FTDD, AR-RMS, and SNTDF. Furthermore, deep learning models such as 1D CNN, RNN, LSTM, and hybrid architectures were employed for a comprehensive analysis. Notably, the LDA classifier achieved the highest F1 score of 88.58% with the SNTDF feature set when trained on hand gesture data of resting and tested across gesture data of all orientations. The promising results from extensive analyses underscore the proposed dataset's potential as a benchmark for advancing gesture recognition technologies, clinical sEMG research, and human-computer interaction applications. The dataset is publicly available in MATLAB format. Access the dataset here. © 2024, CC BY-SA.

关键词： Signal to noise ratio

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Electro-optic Analog-to-Digital Converter Using Spectral Interferometry

Electro-optic Analog-to-Digital Converter Using Spectral Int...

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CLEO: Science and Innovations in CLEO 2024, CLEO: S and I 2024 - Part of Conference on Lasers and Electro-Optics

作者： Shao, Linbo Thomas, Joseph G. Srijanto, Bernadeta R. Lester, Kevin C. Kravchenko, Ivan I. Zhu, Yizheng Bradley Department of Electrical and Computer Engineering Virginia Tech 1185 Perry Street BlacksburgVA24061 United States Virginia Tech Center for Quantum Information Science and Engineering BlacksburgVA24061 United States Center for Nanophase Materials Sciences Oak Ridge National Laboratory Oak RidgeTN37830 United States

We demonstrate an optical analog-to-digital converter (ADC) leveraging spectral interferometry of an integrated electro-optic Mach-Zehnder interferometer on thin-film lithium niobate. The ADC features a high dynamic r... 详细信息

关键词： Mach-Zehnder interferometers

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Effect of radiofrequency coil and primary magnetic field on radiolucent composite plates

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Noise and Vibration Worldwide 2023年第1期54卷 44-58页

作者： Gawande, Atul S Mukka Ramachanra, Shreyas Kamyab, Hesam Trung, Nguyen-Thoi Kattimani, Subhaschandra Department of Mechanical Engineering National Institute of Technology Karnataka Surathkal India Malaysia-Japan International Institute of Technology Universiti Teknologi Malaysia Kuala Lumpur Malaysia Laboratory for Applied and Industrial Mathematics Institute of Computational Science and Artificial Intelligence Ho Chi Minh City Viet Nam Faculty of Mechanical-Electrical and Computer Engineering Van Lang University Ho Chi Minh City Viet Nam

Magnetic Resonance Imaging (MRI) systems need a material compatible with the imaging technique with lesser attenuation and provide accurate images without distortion. Carbon fibers are the best-suited materials for x-ray applications because of their radiolucent properties and reduced attenuation characteristics. However, carbon fiber produces images with distortion in the MRI system by absorbing electromagnetic energy because of its conductive nature. In the present study, five different fiber-reinforced radiolucent composite plates are analyzed to predict their suitability for a radio frequency coil and the effect of a primary magnetic field of 1.5 T and 3.0 T on mechanical responses. Simulation models are built to explore the impact of electromagnetic waves and birdcage coil configurations on composite material and quantify the temperature changes caused due to energy absorption. A multiphysics coupling simulation is being used to understand the effect of stacking sequence, ply orientation, and boundary conditions on the response of composite plates under an electro-magneto-mechanical environment. © The Author(s) 2022.

关键词： Magnetic resonance imaging

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Evaluation of Adaptive Backstepping Control Applied to DFIG Wind System Used on the Real Wind Profile of the Dakhla-Morocco City 6th

Evaluation of Adaptive Backstepping Control Applied to DFIG ...

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6th International Conference on Wireless Technologies, Embedded and Intelligent systems, WITS 2020

作者： Yessef, Mourad Bossoufi, Badre Taoussi, Mohammed Lagrioui, Ahmed El Mahfoud, Mohammed Laboratory of Engineering Modeling and Systems Analysis SMBA University Fez Fez Morocco Laboratory of Technologies and Industrial Services Higher School of Technology SMBA University Fez Fez Morocco Department of Electrical and Computer Engineering Higher National School of Arts and Trades Moulay Ismail University Meknes Meknes Morocco

ISBN: (纸本)9789813368927

The conception of a control strategy of Doubly-Fed Induction Generator (DFIG) for providing a high quality of energy, without harmonic accumulations, to the electric network is a real challenge because of the no-linearity of the system and the variable wind speed. In this work, two commands based on two technics have been developed and then tested in order to control the system and the grid powers, respectively. Note that the main purpose of the control laws is to optimize the extraction of the wind energy in a real context and to push the DFIG working properly with the best performance in both static and dynamic modes. Therefore, the dynamic model turbine has been presented in this paper, also the FOC (Field Oriented Control) and the adaptive Backstepping commands are highlighted. Matlab/Simulink simulations analysis, with real parameters of the turbine and real wind profile of Dakhla-Morocco city, confirm the high accuracy of the adaptive Backstepping command, based on the Lyapunov stability technique, with a total harmonic distortion THD ~0.16%. © 2022, Springer Nature Singapore Pte Ltd.

关键词： Wind turbines

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