Article
Materials Science, Multidisciplinary
Abdulkarem H. M. Almawgani, Vishal Sorathiya, Adam R. H. Alhawari
Summary: This publication presents a fabricated MIMO antenna geometry composed of multiple dipole arrays and its numerical findings from simulations. The study delves into the role of antenna resonators in antenna performance. The characteristics of the antenna, such as return loss, peak gain, bandwidth, polar plot, and electric field distribution, are investigated. The proposed antennas can generate three to seven resonance bands, suiting them for multiband, wideband, and short-band settings. The study's findings have implications for various wireless networking and telecommunications technologies.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2023)
Article
Computer Science, Information Systems
Hossein Malekpoor
Summary: This paper presents a 2x2 array of printed antenna loaded by planar Giuseppe Peano artificial magnetic conductor (AMC) for vehicular wireless systems. The proposed array achieves a wideband antenna with enhanced properties by utilizing diverse polarized directions of the printed dipoles with a 5 x 5 AMC reflector. The measured S-parameters show wide bandwidths and increased stable gains and efficiencies for all elements.
Review
Chemistry, Multidisciplinary
Kaiwen Du, Yongshun Wang, Yao Hu
Summary: This paper reviews the mutual coupling effect in MIMO wireless systems and provides a classification and overview of various decoupling techniques. The additional impacts of different decoupling structures are summarized, and the usability and defects of these techniques are revealed clearly. Finally, a future outlook on the development direction of decoupling techniques for MIMO wireless systems is discussed.
APPLIED SCIENCES-BASEL
(2022)
Article
Computer Science, Hardware & Architecture
Qimei Cui, Zengbao Zhu, Wei Ni, Xiaofeng Tao, Ping Zhang
Summary: This article explores the authentication and compromised user equipment (UE) detection in EI-powered 5G and beyond 5G (B5G) systems, proposing new authentication framework and UE detection method to enhance efficiency and detection rate.
IEEE WIRELESS COMMUNICATIONS
(2021)
Article
Engineering, Electrical & Electronic
Vyacheslav Begishev, Eduard Sopin, Dmitri Moltchanov, Rustam Pirmagomedov, Andrey Samuylov, Sergey Andreev, Yevgeni Koucheryavy, Konstantin Samouylov
Summary: This study develops a mathematical framework using stochastic geometry and queuing theory, utilizing 3GPP cluster-based propagation modeling to capture session-level service dynamics of user equipment that supports multi-band operation. The results show that serving mmWave sessions with microwave BSs is feasible in light traffic conditions, but there are challenges to be aware of.
IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
(2021)
Article
Computer Science, Hardware & Architecture
Jie Hu, Qing Wang, Kun Yang
Summary: This article introduces the utilization of full spectrum in 6G, proposing an energy self-sustainable 6G scheme. By exploiting technologies such as cell-free and airborne access networks, as well as intelligent reflecting surfaces, energy efficiency can be improved. Additionally, utilizing radio-frequency/visible-light signals for wireless information and energy provision enables the realization of zero-energy Internet of Everything devices.
IEEE WIRELESS COMMUNICATIONS
(2021)
Article
Computer Science, Information Systems
Hokuto Taromaru, Hidekazu Murata, Toshiro Nakahira, Daisuke Murayama, Takatsune Moriyama
Summary: Collaboration between mobile stations (MSs) improves signal detection performance and reduces traffic volume on collaboration links. The proposed system utilizes multiple nearby MSs to collaboratively decode MIMO signals from a base station. Multiple decision results obtained from a distributed detection system are used to improve error performance, and residual interference coefficients are used to make final decisions. Through simulations and experiments, the proposed error control scheme achieves a better tradeoff between error performance and collaboration wireless link traffic volume.
Article
Computer Science, Information Systems
Komei Kurasawa, Kota Hashimoto, Aohan Li, Koya Sato, Kensuke Inaba, Hiroki Takesue, Kazuyuki Aihara, Mikio Hasegawa
Summary: This letter presents an ultra-fast and accurate channel assignment approach using a coherent Ising machine for dense wireless LAN systems, demonstrating its ability to improve total throughput performance in a very short time.
IEEE WIRELESS COMMUNICATIONS LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Rongjiang Nie, Li Chen, Nan Zhao, Yunfei Chen, Weidong Wang, Xianbin Wang
Summary: This study analyzes the impact of nonlinear reciprocity mismatch in massive MIMO systems and proposes a calibration method for the base station. The calibration involves using a polynomial function and over-the-air training to estimate the nonlinear mismatch factor and compute calibration coefficients by maximizing downlink achievable rate. Simulation results verify the analytical findings and demonstrate the effectiveness of the proposed calibration approach.
IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
(2021)
Article
Telecommunications
Mohammed Hirzallah, Marwan Krunz, Balkan Kecicioglu, Belal Hamzeh
Summary: The 3GPP has established 5G NR standards to meet the high demand for mobile data, and is also working on extending 5G NR to unlicensed bands with 5G NR-U technology. Studies show that NR-U often achieves higher throughput and lower delay than Wi-Fi, and offers improvements over LTE-LAA.
IEEE TRANSACTIONS ON COGNITIVE COMMUNICATIONS AND NETWORKING
(2021)
Article
Computer Science, Hardware & Architecture
Cise Midoglu, Konstantinos Kousias, Ozgu Alay, Andra Lutu, Antonios Argyriou, Michael Riegler, Carsten Griwodz
Summary: This research focuses on characterizing and evaluating the performance of Mobile Broadband (MBB) networks, with an emphasis on speed as a key Quality of Service (QoS) indicator. Extensive longitudinal measurements were conducted across 2 countries over 2 years, providing insights into the impact of network context, spatio-temporal effects, roaming, and mobility. The study also introduces the concept of adaptive speedtest duration and a proof-of-concept implementation using Machine Learning (ML), while discussing the potential of open datasets to support MBB research and addressing challenges in large scale testbed experimentation.
Article
Engineering, Electrical & Electronic
Upesh Patel, Megh Parekh, Arpan Desai, Trushit Upadhyaya
Summary: The proposed low-profile, tri-band, wide slot antenna is designed for WLAN and WiMAX applications. It features a simple structure using standard FR-4 substrate, achieving tri-band resonance with satisfactory performance metrics.
INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS
(2021)
Article
Astronomy & Astrophysics
Hossein Malekpoor, Mojtaba Shahraki
Summary: This article introduces a novel printed dipole antenna array with a rhomboid AMC reflector, which can achieve a wider bandwidth in the range of 5.27-6.74 GHz and exhibits smaller size, higher gain, and better impedance matching compared to the antenna without AMC.
Article
Computer Science, Information Systems
Vladan M. Jovanovic, Brian T. Cummings
Summary: This paper discusses CDR-based geolocation methods that are grounded in the science of RF engineering, as well as methods that lack a basis in RF theory and engineering practices.
Article
Multidisciplinary Sciences
Jean Boulvert, Gwenael Gabard, Vicente Romero-Garcia, Jean-Philippe Groby
Summary: This work addresses the issue of wave absorption in reciprocal asymmetric scattering by designing and optimizing compact absorbers for perfect unidirectional absorption. The study analyzes the impact of the absorber's structure and coupling on its absorption performance, and provides design guidelines. Experimental results show that the designed absorber achieves high absorption performance within a specific frequency range.
SCIENTIFIC REPORTS
(2022)
Article
Computer Science, Information Systems
A. Garcia-Collado, G. Molina-Cuberos, O. Fernandez, J. Margineda
IEEE LATIN AMERICA TRANSACTIONS
(2020)
Article
Computer Science, Information Systems
Luis Valle, Jesus R. Perez, Rafael P. Torres
Article
Computer Science, Information Systems
Rafael P. Torres, Jesus R. Perez
Summary: This paper derives a lower bound for the coherence block (ChB) length in mobile radio channels and discusses its practical importance for wireless systems. It highlights the easily measurable parameters involved in the bound derivation and the impact of coherence on the results.
Article
Computer Science, Information Systems
Oscar Fernandez, Tomas Fernandez, Alvaro Gomez
Summary: This work presents a novel and efficient band-stop filter using microstrip technology to reduce channel interferences caused by the allocation of part of the UHF band to 4G and 5G services in the digital terrestrial television frequency band. The filter provides high performance and compact subwavelength size, suitable for installation at the input of the TV terminal or integrated with the balun at the rooftop antenna.
Article
Computer Science, Information Systems
Jesus R. Perez, Oscar Fernandez, Luis Valle, Abla Bedoui, Mohamed Et-tolba, Rafael P. Torres
Summary: This paper presents a measurement-based comparison between distributed and concentrated massive MIMO systems in an indoor environment with a 400 MHz bandwidth centered at 3.5 GHz. The performance of both systems in the up-link is characterized in terms of sum capacity, spectral efficiency, user fairness, and the impact of power imbalance. The differences in channel performance between the two systems are explained through the observation of their respective measured channel matrices. The deployment of systems and distribution of users in the measurement environment are realistically arranged to avoid interference from human movement.
Article
Engineering, Electrical & Electronic
Rafael P. Torres, Jesus R. Perez, Luis Valle
Summary: In this letter, a comparative analysis is presented on the hardening effect of concentrated and distributed massive multiple-input-multiple-output channels (C-mMIMO and D-mMIMO, respectively). The analysis is conducted in two buildings with similar structural characteristics, considering the frequency bands of 3.5 and 26 GHz for 5G deployments. Experimental data at 3.5 GHz and simulation results at 26 GHz using a rigorous ray tracing method are used. Both measurements and simulations show that indoor environments provide a sufficiently high level of hardening for mMIMO systems, contributing to the reliability of communication systems or sensor networks.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2023)
Article
Computer Science, Information Systems
Lorenzo Rubio, Vicent M. Rodrigo Penarrocha, Marta Cabedo-Fabres, Bernardo Bernardo-Clemente, Juan Reig, Herman Fernandez, Jesus R. Perez, Rafael P. Torres, Luis Valle, Oscar Fernandez
Summary: In this paper, the path loss characterization at millimeter-wave frequencies in a typical indoor office environment is studied. The path loss results are derived from measurements collected in the 25-40 GHz frequency band under both line-of-sight and obstructed-LOS conditions. Different models, including the close-in free space reference distance and floating-intercept models, are used to analyze the path loss at different frequencies. The results provide valuable insights into the propagation behavior at mmWave frequencies and are helpful for the simulation and performance evaluation of future wireless communication systems in indoor hotspot environments.
Article
Engineering, Electrical & Electronic
Jihad Ben Yamoun, Oscar Fernandez, Noura Aknin, Alvaro Gomez-Gomez
Summary: This study analyzes the extrinsic chirality of metamaterials based on printed circuit board (PCB). Two novel 3-D chiral metamaterials (CMMs) called sawtooth and zigzag arrangements are proposed and analyzed. Numerical and experimental characterization show that these new types of arrangements exhibit a larger circular dichroism (CD) with a significant wideband response compared to the traditional planar extrinsic chiral structures.
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
(2023)
Proceedings Paper
Engineering, Electrical & Electronic
O. Fernandez, J. Ben Yamoun, A. Gomez
Summary: This study investigates the behavior of a chiral metamaterial in modifying the polarization state of incident plane waves. The authors explore two different arrangements, sawtooth and zigzag profiles, and utilize a mutual twist rosette to combine intrinsic and extrinsic chirality. The findings demonstrate improved optical activity and/or circular dichroism.
2022 PHOTONICS & ELECTROMAGNETICS RESEARCH SYMPOSIUM (PIERS 2022)
(2022)
Article
Computer Science, Information Systems
Jesus R. Perez, Luis Valle, Oscar Fernandez, Rafael P. Torres, Lorenzo Rubio, Vicent M. Rodrigo Penarrocha, Juan Reig
Summary: This paper presents a comparative analysis of concentrated and distributed massive MIMO channels in an indoor environment using ray-tracing. The results show that the distributed MIMO channel outperforms the concentrated MIMO channel in terms of broadband behavior and achievable capacity.
Article
Computer Science, Information Systems
Jesus R. Perez, Rafael P. Torres, Marta Domingo, Luis Valle, Jose Basterrechea
Article
Computer Science, Information Systems
Jesus R. Perez, Rafael P. Torres
