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Dual-band multiple-input multiple-output antenna based on half split cylindrical dielectric resonator

JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS 2018年第9期32卷 1152-1163页

作者： Sharma, Abhishek Sarkar, Anirban Biswas, Animesh Akhtar, M. Jaleel Indian Inst Technol Kanpur Dept Elect Engn Kanpur Uttar Pradesh India

In this article, a dual-band half split cylindrical dielectric resonator antenna is proposed for multiple-input multiple-output (MIMO) applications. The dual-band operation is achieved by simultaneously exciting TE01 delta and TE02 delta modes in an aperture coupled fed half split cylindrical dielectric resonator. The topology of four element MIMO antenna is such that it provides both spatial and polarization diversities. Over both the operating bands, the measured port-toport isolation is better than 20 dB. The proposed antenna exhibits broadside radiation with cross polarization level below -15 dB in both xz-and yz-plane. The peak gain of antenna is 4.88 and 5.32 dBi at lower and upper operating frequency, respectively. The MIMO performance of the proposed antenna is found to be good with ECC<0.06. Moreover, the channel capacity of the proposed MIMO is near to uncorrelated case for uniform propagation scenario. The proposed antenna could be suitable for LTE 22/LTE 42 and WLAN applications.

关键词： Dielectric resonator antenna LTE polarization diversity multiple-input multiple-output spatial diversity WLAN

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Novel Movement-Based Methods for the Calibration of Colocated multiple-input multiple-output Radars

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IEEE ACCESS 2023年 11卷 116090-116108页

作者： Guerzoni, Giorgio Faghand, Elahe Vitetta, Giorgio Matteo Vincenzi, Loris Mehrshahi, Esfandiar Univ Modena & Reggio Emilia Dept Engn Enzo Ferrari I-41124 Modena Italy Shahid Beheshti Univ Fac Elect Engn Dept Telecommun Tehran *** Iran

It is well-known that the availability of transmit and receive arrays in colocated multiple-input multiple-output radar systems can be exploited to detect multiple targets, and estimate their range and angular coordinates. Unluckily, the accuracy achieved in the estimation of target parameters can be severely affected by hardware nonidealities. The impact of these nonidealities can be mitigated through the adoption of specific methods explicitly developed to estimate and compensate for them, i.e., briefly, of calibration methods. As far as we know, until now, most of the calibration techniques proposed in the technical literature for colocated multiple-input multiple-output radars are based on the idea of placing one or more reference targets in front of the considered radar device at perfectly known and fixed locations, and quantifying the difference between the expected radar image and the measured one. In this manuscript, two novel calibration methods are proposed. Both exploit the measurements captured by a colocated multiple-input multiple-output radar device at multiple positions;for this reason, the acquisition of such measurements involves the movement of the radar. The first one does not require any knowledge about the nature, number, position or radar cross section of the reference targets, provided that all these are in far-field;the second one, instead, needs a single reference target in near-field conditions, with the only constraints for it to be pointwise and isolated from stray targets in the range domain. This drastically simplifies the experimental setup to be employed for radar calibration. The proposed methods are tested on a commercial radar device and compared with a traditional method for radar calibration.

关键词： Calibration multiple-input multiple-output radar synthetic aperture radar

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Performance enhancement for a non-orthogonal multiple access system using 4 x 4 multiple-input multiple-output visible-light communication

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OPTICAL ENGINEERING 2020年第12期59卷 126104-126104页

作者： Elewah, Ibrahim A. Jasman, Faezah Ng, Shashiong Univ Sains Malaysia Inst Nano Optoelect Res & Technol George Town Malaysia Amer Coll Middle East Dept Engn & Technol Kuwait Kuwait

A multi-user visible-light communication (VLC) system based on 4 x 4 multiple-input multiple-output (MIMO) was investigated. The system consists of four light-emitting diodes (as a transmitter) and four photodetectors (as a receiver). The proposed system was simulated for two, three, and four users. The objective of this study is to optimize the system power consumption and to utilize the sum rate on the system coverage area. By expanding the system from a 2 x 2 MIMO-VLC to a 4 x 4 MIMO-VLC, the results demonstrate that the total sum rate of the system can be improved. The findings reveal that the 4 x 4 MIMO-VLC achieves a maximum sum-rate enhancement of 143% compared with the 2 x 2 MIMO-VLC. The results also show that the efficiency of 4 x 4 MIMO-VLC system with non-orthogonal multiple access (NOMA) and gain ratio power allocation (GRPA) was increased by around 181% compared to 2 x 2 MIMO-NOMA-based VLC with GRPA in combination. For the 4 x 4 MIMO-NOMA-VLC device with GRPA, the sum bit rate for two, three, and four users was increased by 40%, 33%, and 24%, respectively. Through this study, it can be concluded that GRPA scheme plays an important role in utilizing MIMO-VLC system sum rate of the MIMO-VLC system. (c) The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

关键词： visible-light communication multiple-input multiple-output non-orthogonal multiple access gain ratio power allocation

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Reduced complexity lattice-based multiple-input multiple-output schemes

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IET COMMUNICATIONS 2019年第10期13卷 1472-1481页

作者： Ouni, Nizar Tourki, Kamel Mohaisen, Manar Bouallegue, Ridha Univ Carthage Higher Sch Commun InnovCom Lab Tunis Tunisia Univ Tunis El Manar Natl Engn Sch Tunis Tunis Tunisia Huawei Technol Co France Res Ctr Math & Algorithm Sci Lab Paris France Korea Univ Technol & Educ Dept Elect Elect & Commun Engn Cheonan South Korea

multiple-input multiple-output is being considered as a highly interesting topic for the new generation of wireless communication systems. The major challenge is how to enhance the link reliability while neither affecting the spectral efficiency nor the quality of service. To reduce the complexity of the maximum likelihood (ML) receiver, efforts have been focused on zero forcing (ZF) decoder using lattice reduction-aided (LRA) techniques. In this study, the authors propose a method that improves performance using the LRA-based precoding technique without increasing the decoder complexity. Their approach is to exploit the channel matrix to generate matrices for both the precoding and LRA detection technique. This makes it possible to achieve maximum orthogonality for the generated channel matrices while reducing considerably the noise effect. They focus on the use of the LRA-ZF for the ease of its implementation and low complexity. The proposed method outperforms LRA-minimum mean square error-based receiver and gets closer to ML receiver performance. The performance and complexity of the proposed scheme are discussed.

关键词： precoding matrix algebra MIMO communication least mean squares methods reduced complexity lattice-based multiple-input multiple-output schemes multiple-input multiple-output highly interesting topic wireless communication systems link reliability spectral efficiency quality of service maximum likelihood receiver lattice reduction-aided techniques LRA-based decoder complexity precoding generated channel matrices LRA-ZF low complexity LRA-minimum mean square error-based receiver ML receiver performance

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Simplified log likelihood ratio calculation in soft ordered successive interference cancellation for multiple-input multiple-output digital video broadcasting-second generation terrestrial receivers

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IET COMMUNICATIONS 2014年第18期8卷 3280-3289页

作者： Kang, In-Woong Lee, Young-Jun Kim, Youngmin Seo, Jae Hyun Kim, Heung Mook Kim, Hyoung-Nam Pusan Natl Univ Dept Elect & Comp Engn Pusan South Korea ETRI Broadcasting Syst Res Dept Taejon South Korea

This study proposes a soft ordered successive interference cancellation (OSIC) receiver accompanied by a simplified log-likelihood ratio calculation method for a dual-polarised multiple-input multiple-output (MIMO) digital video broadcasting-second generation terrestrial system. The future terrestrial transmission systems will be required to provide high data rates for ultra-high definition television service. For this purpose, dual-polarised MIMO techniques with a little cross-antenna interference and high-order modulation schemes have been considered. As the cross-antenna interference needs to be removed, a soft OSIC receiver can be used effectively. However, the receiver has to endure high computational complexity for calculating soft values. To reduce it, the authors simplified the calculation based on the decision threshold (DT) method. The main contribution of this study is to extend the conventional DT method, which is restricted to only low-order modulations, to an algorithmic process applicable to any modulation order. The proposed soft OSIC receiver has about 1 dB degradation from the soft OSIC receiver with the maximum-likelihood calculation of soft values. The degradation can be fully rewarded by the significantly reduced computational complexity. Furthermore, this study presents an additional possibility of improving the decoding performance by modelling the OSIC equaliser as a biased estimator.

关键词： interference suppression MIMO communication television receivers digital video broadcasting television antennas modulation decoding equalisers communication complexity high definition television antenna arrays soft ordered successive interference cancellation multiple-input multiple-output digital video broadcasting-second generation terrestrial receivers dual-polarised MIMO techniques log-likelihood ratio calculation method digital video broadcasting second generation terrestrial system terrestrial transmission systems ultra-high deflnition television service cross-antenna interference high-order modulation schemes soft OSIC receiver computational complexity decision threshold method low-order modulations algorithmic process maximum-likelihood calculation decoding performance OSIC equaliser biased estimator

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A new layered space-time detection algorithm for frequency selective fading multiple-input multiple-output channels based on particle filter

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CHINESE PHYSICS 2006年第11期15卷 2481-2488页

作者： Du Zheng-Cong Tang Bin Liu Li-Xin Univ Elect Sci & Technol China Coll Elect Engn Chengdu 610054 Peoples R China Panzhihua Univ Panzhihua 617000 Peoples R China

In this paper, a new observation equation of non-Gaussian frequency selective fading Bell Labs layered space time (BLAST) architecture system is proposed, which is used for frequency selective fading channels and non-Gaussian noise in an application environment of BLAST system. With othogonal matrix triangularization (QR decomposition) of the channel matrix, the static observation equation of frequency selective fading BLAST system is transformed into a dynamic state space model, and then the particle filter is used for space-time layered detection. Making the full use of the finite alphabet of the digital modulation communication signal, the optimal proposal distribution can be chosen to produce particle and update the weight. Incorporated with current method of reducing error propagation, a new space-time layered detection algorithm is proposed. Simulation result shows the validity of the proposed algorithm.

关键词： particle filter multiple-input multiple-output layered space-time structure frequency selective fading channels

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Compact planar near-field resonant parastic antenna for multiple-input multiple-output applications

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MICROWAVE AND OPTICAL TECHNOLOGY LETTERS 2012年第3期54卷 580-584页

作者： Lin, Chia-Ching Jin, Peng Ziolkowski, Richard W. Univ Arizona Dept Elect & Comp Engn Tucson AZ 85721 USA Ruckus Wireless Sunnyvale CA 94085 USA Broadcom Corp Signal Integr Grp Irvine CA 92617 USA

A planar tri-band near-field resonant parasitic (NFRP) antenna for multiple-input multiple-output (MIMO) applications in the WLAN 2.4/5.2/5.8 GHz bands is presented. The tri-band functionality is obtained by introducing three different resonant parasitic elements near a simple driven element. Good impedance matching, radiation efficiency, and antenna patterns are realized at each of the desired resonant frequencies. Experimental confirmation of the simulated performance is presented. It is demonstrated that an array of these tri-band NFRP antennas obtains good isolation between elements even with small spacing between them. Calculated envelope correlation values are less than 0.12 within the bands of interest. The design methodologies of the tri-band NFRP antenna and the corresponding MIMO array are detailed. (C) 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:580-584, 2012;View this article online at ***. DOI 10.1002/mop.26647

关键词： antenna antenna pattern input impedance multiple-input multiple-output parasitic antenna

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Phase and Channel Estimation for High-Capacity Phase-Asynchronous Mode-Division multiplexing multiple-input multiple-output Free-Space Optical Communications in Strong Turbulent Channels

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JOURNAL OF LIGHTWAVE TECHNOLOGY 2024年第11期42卷 4132-4143页

作者： Li, Yiming Chen, Zhaozhong Patel, Mohammed Lavery, Martin P. J. Ellis, Andrew D. Aston Univ Aston Inst Photon Technol Birmingham B4 7ET England Univ Glasgow James Watt Sch Engn Glasgow G12 8QQ Scotland

In this paper, we propose a novel pilot-aided phase and channel estimation algorithm for coherent mode-division multiplexing multiple-input multiple-output free-space optical communication system. This algorithm enables the implementation of advanced multiple-input multiple-output decoders, leading to a significantly better bit error rate performance. This algorithm also supports phase-asynchronous light sources at each transmit and receive channel, significantly reducing the hardware requirements. Moreover, it has low computational complexity and Cram & eacute;r-Rao lower bound approaching estimation performance. In our proof-of-concept experiment, we employed 10 decorrelated channels to achieve a record-high 689.2 Gbit/s/wavelength line rate in strong turbulence, verifying the feasibility of our phase and channel estimation algorithm.

关键词： Channel estimation Estimation MIMO communication Phase noise Symbols Decoding Vectors Atmospheric turbulence channel estimation free-space optics multiple-input multiple-output

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Hybrid Two-Stage Decision-Feedback Equalization for Single-Carrier multiple-input multiple-output Systems

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IEICE TRANSACTIONS ON COMMUNICATIONS 2009年第7期E92B卷 2503-2506页

作者： Feng, Ang Yin, Qinye Fan, Jiancun Xi An Jiao Tong Univ Elect & Informat Engn Dept Xian 710049 Peoples R China

A single-carrier multiple-input multiple-output (MIMO) system with frequency-selective channels suffers from the inter-symbol interference (ISI) and the co-channel interference (CCI). To eliminate both type of interference, we propose in this letter a hybrid two-stage decision-feedback equalizer (HTS-DFE), which performs the frequency-domain equalization (FIDE) in the first stage and the layered serial interference-cancellation (SIC) in the second stage. Since the decision-feedback (DF) or noise-prediction (NP) architecture can be employed in FIDE or SIC, the proposed equalizer actually can have four variations that achieve the same mean square error (MSE) under the assumption of perfect feedback. Further, we combine HTS-DFE with the decoded decision-feedback (131317) scheme to mitigate the error-propagation encountered in the practice. Simulation results confirm that the proposed HTS-DFE can outperform the existing equalizers significantly.

关键词： single-carrier multiple-input multiple-output noise prediction decision-feedback equalization

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An adaptive control algorithm for harmonic cancellation in multiple-input multiple-output vibration systems

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JOURNAL OF VIBRATION AND CONTROL 2024年第17-18期30卷 3837-3849页

作者： Xu, Zhenyu Li, Chao Chen, Zhangwei Zhejiang Univ State Key Lab Fluid Power & Mech Syst Hangzhou Peoples R China Zhejiang Univ State Key Lab Fluid Power & Mech Syst Yuhangtang Rd 866 Hangzhou 310058 Peoples R China

This paper presents a time-domain adaptive algorithm designed to eliminate harmonics in a multiple-input multiple-output (MIMO) system, taking into account its coupling characteristics. The algorithm is an improvement over the X-filtered LMS (FxLMS) algorithm, and is specifically tailored to the triaxial vibration system. The proposed algorithm has been shown to achieve high convergence, even in the presence of identification errors, as confirmed through both theoretical derivation and numerical simulations. To validate the efficacy of the proposed MIMO harmonic cancellation algorithm, it was tested on a genuine triaxial vibration system. The experimental results clearly demonstrate that the algorithm effectively reduces the output harmonic disturbance of the three axes' frequency components.

关键词： Triaxial vibrator harmonic cancellation adaptive control FxLMS algorithm multiple-input multiple-output

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