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multiple input multiple output dielectric resonator antenna with circular polarized adaptability for 5G applications

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JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS 2020年第9期34卷 1180-1194页

作者： Singhwal, S. S. Kanaujia, B. K. Singh, A. Kishor, J. Matekovits, L. Uttarakhand Tech Univ Dept Elect & Commun Engn Dehra Dun Uttarakhand India HMR Inst Technol & Management Dept Elect & Commun Engn Delhi India Jawaharlal Nehru Univ Sch Computat & Integrat Sci Delhi India BTK Inst Technol Dept Comp Sci & Engn Dwarahat Uttarakhand India IMS Engn Management Tech Campus Greater Noida Dept Elect & Commun Engn Noida India Politecn Torino Dipartimento Elettron & Telecomunicaz Turin Italy

In this paper, the concept of the circularly polarized agile, multiple-input multiple-output (MIMO) dielectric resonator antenna (DRA) structure for fifth generation (5G) new radio application in mobile terminal is presented. Two prototypes have been fabricated, namely one with cylindrical DRA (CDRA) referred as A1 and a second one with ring DRA (RDRA) named as A2. These practical realizations of dual-port MIMO antennas have been mounted on a Rogers 5870 substrate of octagonal shape with proper ground architecture. The proposed dual-port MIMO antennas have been excited with conformal probes and L-type feed network aiming to achieve circular polarization (CP). Measured impedance bandwidth of A1 and A2 are 21.2% (3.15-3.9 GHz) and 22.2% (3.12-3.9 GHz), respectively. Moreover, for both antennas low mutual coupling between ports with minimum isolation of dB over entire impedance bandwidth has been obtained by using triangular head slots in the ground plane. Measured axial ratio bandwidths in broadside direction are 5.66% (3.26-3.45 GHz) and 4.25% (3.45-3.6 GHz), respectively. Maximum gains are 7.3 and 7.2 dBi, in that order. MIMO antenna parameters such as envelope correction coefficient, diversity gain (DG), mean effective gain and total active reflection coefficient are also calculated to verify MIMO performance parameters. The proposed antennas also demonstrate CP agility with insertion of concentric cylindrical shells of different radii.

关键词： Circular polarization dielectric resonator antenna multiple input multiple output 5G

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multiple input multiple output CDSK Chaotic Communication System and Its Performance Analysis

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Wuhan University Journal of Natural Sciences 2016年第3期21卷 221-228页

作者： DUAN Junyi JIANG Guoping YANG Hua School of Communication and Signal Nanjing Institute of Railway Technology School of Communication and Information Engineering Nanjing University of Posts and Telecommunications

This paper propose a novel noncoherent chaotic com- munication scheme named multiple-input multiple-output correlation-delay-shill- keying （MIMO-CDSK）. In this scheme, multiple antennas are employed to strengthen the robustness in transmission, and to get more diversity gain. The bit error rate （BER） of the MIMO-CDSK is studied analytically in AWGN channel model and multipath fading channel model. The theory and simulation results show that, the performance gain can be obtained with multiple antennas allocated in the transmitter and receiver. Moreover, it is observed that MIMO-CDSK system can effectively reduce the multipath interference.

关键词： multiple input multiple output correlation delayshift keying (CDSK) AWGN (additive white Gaussian noise)channel model multipath fading channel model diversity gain

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Channel Estimation for the Multiuser Multi-panel Massive multiple input multiple output System

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WIRELESS PERSONAL COMMUNICATIONS 2024年第4期138卷 2677-2698页

作者： Ghadiri, Abbas Atashbar, Mahmoud Mohassel Feghhi, Mahmood Azarbaijan Shahid Madani Univ Fac Engn Tabriz Iran Univ Tabriz Fac Elect & Comp Engn Tabriz Iran

The size and weight of Massive multiple input multiple output (mMIMO) significantly increase with the addition of more antennas. The 3rd Generation Partnership Project standardization group addressed these issues by incorporating the multi-panel feature into New Radio communications. The estimated value of the channel is essential for signal detection and precoding in mMIMO. Traditional channel estimation methods are ineffective in multi-panel mMIMO system because of its hybrid structure and non-uniform antenna array structure. This paper introduces a novel channel estimation technique for multi-panel mMIMO systems operating in multiuser scenario by transforming the channel estimation problem into an angular domain block sparse signal recovery problem. We propose a generalized block orthogonal matching pursuit (GB-OMP) method to solve the obtained sparse model. The proposed method incorporates a well-designed pilot sequence for optimal performance. The proposed GB-OMP method outperforms the reference method, as shown by the simulation results.

关键词： Channel estimation Multi-panel Multiuser multiple input multiple output

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Global stabilization control for multiple input multiple output nonlinear systems with unknown function vector

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INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL 2023年第11期33卷 6496-6511页

作者： Jia, Fujin Lu, Junwei Li, Yongmin Anhui Univ Sch Elect Engn & Automat Hefei Peoples R China Nanjing Univ Sci & Technol Sch Automat Nanjing Peoples R China Nanjing Normal Univ Sch Elect & Automat Engn Nanjing Peoples R China Huzhou Univ Sch Sci Huzhou Peoples R China

In this article, a control algorithm is proposed to solve the global stabilization control problem of multiple input multiple output (MIMO) nonlinear systems with unknown function vectors (UFVs). Firstly, a Lemma dealing with UFVs is proposed. Then, combined with the backstepping method, the controller is designed such that all signals of the closed-loop system are globally stable. Compared with the approximation method, the algorithm in this article solves the global stabilization control problem. Compared with the assumptions of UFVs, the algorithm in this article reduces the conservatism problem. At the same time, the algorithm in this article also solves the "explosion of terms" problem of backstepping. Compared with the methods to solve this problem: dynamic surface control (DSC) and direct fuzzy control, the algorithm in this article can make all signals of the closed-loop system converge to the origin. Finally, the algorithm is applied to the model of spacecraft with modified Rodrigues parameters, and the simulation results show the effectiveness of this algorithm.

关键词： backstepping global stabilization control multiple input multiple output nonlinear systems

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Approximate ergodic capacity of multiuser massive multiple input multiple output in a Rayleigh fading uplink channel with variance profile

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IET COMMUNICATIONS 2015年第6期9卷 844-852页

作者： Kazemi, Mohammad Aghaeinia, Hassan Amirkabir Univ Technol Dept Elect Engn Tehran Polytech Tehran Iran

The effect of large-scale fading variations over massive multiple input multiple output (MIMO) antenna array on sum-capacity of massive MIMO system has not been thoroughly investigated in the literature. This study considers a multiuser massive MIMO system with a Rayleigh fading channel that takes into account large-scale fading variations over base station antenna array. Two scenarios are investigated: distributed antenna base station and linear array base station. In both scenarios, the authors obtain an approximate closed-form expressions for uplink ergodic sum-capacity for both low and high signal-to-noise ratio (SNR) regimes. It is shown that the proposed closed-form expressions are accurate in a wide range of practical SNRs;for example, the approximation error is below 10% for SNRs lower than -10 dB and higher than 17 dB for low-SNR and high-SNR closed-form expressions, respectively. It is also shown that the proposed closed-form expressions are not only valid for massive MIMO scenario but also for a system with a few number of base station antennas. The numerical results show that the proposed closed-form expressions have much less computational complexity than previous works.

关键词： multiuser channels MIMO communication Rayleigh channels channel capacity approximation theory linear antenna arrays large scale fading variation effect multiple input multiple output MIMO antenna array multiuser massive MIMO system Rayleigh fading channel base station antenna array distributed antenna base station linear array base station approximate uplink ergodic sum capacity signal-to-noise ratio SNR

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multiple input multiple output Resonant Inductive WPT Link: Optimal Terminations for Efficiency Maximization

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ENERGIES 2021年第8期14卷 2194-2194页

作者： Monti, Giuseppina Mongiardo, Mauro Minnaert, Ben Costanzo, Alessandra Tarricone, Luciano Univ Salento Dept Engn Innovat I-73100 Lecce Italy Univ Perugia Dept Engn I-06123 Perugia Italy Odisee Univ Coll Appl Sci B-9000 Ghent Belgium Univ Bologna Dept Elect I-40126 Bologna Italy

In this paper a general-purpose procedure for optimizing a resonant inductive wireless power transfer link adopting a multiple-input-multiple-output (MIMO) configuration is presented. The wireless link is described in a general-purpose way as a multi-port electrical network that can be the result of either analytical calculations, full-wave simulations, or measurements. An eigenvalue problem is then derived to determine the link optimal impedance terminations for efficiency maximization. A step-by-step procedure is proposed to solve the eigenvalue problem using a computer algebra system, it provides the configuration of the link, optimal sources, and loads for maximizing the efficiency. The main advantage of the proposed approach is that it is general: it is valid for any strictly-passive multi-port network and is therefore applicable to any wireless power transfer (WPT) link. To validate the presented theory, an example of application is illustrated for a link using three transmitters and two receivers whose impedance matrix was derived from full-wave simulations.

关键词： resonant coils wireless power transfer inductive coupling optimal load multiple input multiple output power gain

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Reconfigurable wide band wearable multiple input multiple output antenna with hanging resonator

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MICROWAVE AND OPTICAL TECHNOLOGY LETTERS 2020年第3期62卷 1352-1359页

作者： Biswas, Ashim Kumar Chakraborty, Ujjal NIT Silchar Dept Elect & Commun Engn Silchar Assam India

This letter presents a two-element textile-based multiple input multiple output (MIMO) antenna with switchable dual wide band characteristics. The antenna is integrated with two switches enabled hanging resonators and a partial ground plane with funnel-shaped DGS. It covers the spectra from 3.11 to 5.15 GHz in one and 4.81 to 7.39 GHz in another switching condition. The antenna satisfies the WiMAX/C-band downlink (3.2-3.8/3.7-4.2 GHz) and WLAN/C-band uplink (5.15-5.35/5.72-5.825/5.925-6.425 GHz) application bands. The resonator structures provide very high port isolation of >19.5 and >21 dB in the lower and upper band, respectively. The proposed antenna offers suitable values of diversity parameters which include envelope correlation coefficient (ECC < 0.18), diversity gain (DG > 9.9 dB), and channel capacity loss (CCL < 0.2 BPS/Hz). The simulated results are found to be in close agreement with the measured outcomes from the experiments. The proposed antenna proves to be promising for wearable MIMO applications.

关键词： hanging resonator multiple input multiple output port isolation reconfigurable wearable antenna

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Model predictive control relevant identification: multiple input multiple output against multiple input single output

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IET CONTROL THEORY AND APPLICATIONS 2010年第9期4卷 1756-1766页

作者： Lauri, D. Salcedo, J. V. Garcia-Nieto, S. Martinez, M. Univ Politecn Valencia Inst Univ Automat & Informat Ind Valencia 46022 Spain

Model predictive control (MPC) relevant identification (MRI) can be performed by minimising a cost function containing identification errors from multistep ahead predictions. The multiple MISO (multiple input single output) identification approach is often preferred to the MIMO (multiple input multiple output) identification approach in traditional one-step ahead identification. This study aims at comparing the MIMO and multiple MISO identification approaches in MRI. It is argued in this study that, unlike in the one-step ahead approach, MIMO identification is preferable in MRI. As an example, a non-linear MIMO proton exchange membrane fuel cell (PEMFC) is approximated in the neighbourhood of an operating point using the MIMO and MISO approaches.

关键词： model relevant identification multiple input multiple output multivariable control systems identification errors MRI identification MPC Simulation, modelling and identification predictive control MIMO systems Multivariable control systems MISO model predictive controller MIMO Optimal control multiple input single output

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Two- and four-channel-incoherent multiple input multiple output system operating over multimode fiber

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MICROWAVE AND OPTICAL TECHNOLOGY LETTERS 2012年第4期54卷 940-943页

作者： Siuzdak, Jerzy Kowalczyk, Marcin Warsaw Univ Sci & Technol Inst Telekomunikacji PL-00665 Warsaw Poland

This article presents realization of two- and four-channel-incoherent multiple input multiple output systems operating over 4.4 km of 50-mu m core silica multimode *** system featured 1/2QPSK modulation, 10 Mbit/s per channel, sampling of the received signals, and off-line postprocessing. The quality of the received signals was acceptable only for 2 X 2 system, whereas for 4 X 4 system some channels experienced temporary fading. (c) 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:940943, 2012;View this article online at ***. DOI 10.1002/mop.26680

关键词： fiber optics optical communications multiple input multiple output multimode fiber RF carrier

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Bit Error Rate (BER) Improvement of multiple input multiple output Orthogonal Frequency Division multiplexing (MIMO-OFDM) System Using Bit Level Scrambling 12

Bit Error Rate (BER) Improvement of Multiple Input Multiple ...

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12 IEEE Int C Elect Energy Env Communications Computer Control

作者： Sheikh, Javaid Ahmad Uzma Parah, Shabir A. Bhat, G. Mohiuddin Univ Kashmir Post Grad Dept Elect & IT Srinagar Jammu & Kashmir India

ISBN: (纸本)9781467365406

The work in the field of wireless communication these days is directed towards the efficient usage of the available spectrum as the spectrum scarcity keeps haunting people in general and communication engineers in particular. This puts an upper limit on the development of new spectrum hungry applications. Spectral efficiency has thus given new direction to the researchers to look for the available option for better utilization of spectrum and to develop techniques that will be compatible with the existing technology. The work presented in this paper is also an attempt towards this direction. The idea is to use the multiple input multiple output Orthogonal Frequency Division multiplexing (MIMO-OFDM) for transmission of image data with improved Bit Error Rate (BER) and Pixel Error Rate (PER) as the performance of most of the communication systems developed is measured, in the most common parlance, in terms of BER. The bit error has been improved using bit level scrambling in addition to the convolutional coding. A MATLAB program has been developed to model the MIMO-OFDM system. The model under consideration prompts the user for various inputs and then produces the results in terms of various plots and graphs. The results confirm the significant improvement in the BER and PER of the system.

关键词： Multicarrier Modulation Orthogonal Frequency Division multiplexing multiple input multiple output Diversity Spectral Efficiency

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