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High-Spatial-Diversity Imaging Receiver Using Fisheye Lens for Indoor MIMO VLCs

IEEE PHOTONICS TECHNOLOGY LETTERS 2014年第22期26卷 2260-2263页

作者： Chen, Te Liu, Lu Tu, Bo Zheng, Zhong Hu, Weiwei Peking Univ State Key Lab Adv Opt Commun Syst & Networks Beijing 100871 Peoples R China

This letter proposes an imaging receiver scheme for an indoor multiple-input-multiple-output (MIMO) visible light communication (VLC), in which a fisheye lens with ultrawide field-of-view is used for high-quality imaging, so it can realize omnidirectional receiving and provide high-spatial diversity for decoding of the MIMO signals. In addition, the fisheye lens projects planar and small-sized images, which means that the integration with compact planar receiver array is feasible. Using the polynomial projection model, the optical intensity on the receiving plane is obtained, which is in accordance with the experimental result and shows that the images of the light-emitting diodes are clearly separated. The simulation results indicate that low correlations of the channel matrix are achieved, so high spectral efficiency is realized with various receiver positions under indoor circumstance. Consequently, this fisheyelens-based imaging receiver is a potential candidate for high-performance indoor MIMO VLC applications.

关键词： Visible light communications imaging receiver fisheye lens multiple-input-multiple-output spatial diversity

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An efficient MIMO-OFDM VLC system of combining space time block coding with orthogonal circulant matrix transform precoding

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OPTICS COMMUNICATIONS 2020年 473卷 125993-125993页

作者： Chen, Mengru Lu, Huimin Chen, Danyang Jin, Jianli Wang, Jianping Univ Sci & Technol Beijing Sch Comp & Commun Engn Beijing 100083 Peoples R China

An efficient precoding scheme combining space-time block code (STBC) and orthogonal circulant matrix transform (OCT) is proposed to improve the performance of multiple input-multiple output-orthogonal frequency division multiplexing (MIMO-OFDM) based visible light communication (VLC) systems in this work. An experimental 2x2 MIMO-OFDM VLC system is designed and setup to evaluate the performance of the proposed STBC-OCT precoding scheme, which bit error rate (BER) performance is investigated experimentally for different sample rates, amplitudes and quadrature amplitude modulation (QAM) order. It is shown that the system using proposed STBC-OCT precoding has more excellent BER performance compared with the system using other precoding methods, and 157.5 Mbit/s transmission rate can be realized for the MIMO VLC system with 0.5 m distance. This is because that the proposed scheme can effectively alleviate the bandwidth limitation issue of the VLC system and offers the optimal reliability.

关键词： Visible light communication multiple-input-multiple-output Orthogonal circulant matrix transform Space-time block code

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A Four-Port MIMO Antenna Using Concentric Square-Ring Patches Loaded With CSRR for High Isolation

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IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS 2016年 15卷 1196-1199页

作者： Ramachandran, Anitha Pushpakaran, Sarin Valiyaveettil Pezholil, Mohanan van Kesavath, Vasude Cochin Univ Sci & Technol Dept Elect Ctr Res Electromagnet & Antennas CREMA Cochin 682022 Kerala India Govt Coll Dept Elect Chittur 678104 Palakkad India

A novel four-port multiple-input multiple-output (MIMO) antenna system is designed using concentric square-ring patch antennas. All four ports are made to resonate at 2.4 GHz ISM band with an overall system dimension of 60 x 60 x 1.6 mm(3). This design uses complementary split-ring resonator (CSRR) loaded on its ground plane for enhanced isolation of 22 dB between patch antenna elements. CSRR reduces mutual coupling by about 6.5 dB. The antenna operates with a 2:1 VSWR bandwidth of 75 MHz centered at 2.45 GHz. This collocated antenna system satisfies MIMO diversity performance with low envelope correlation between its waveforms. The effectiveness of concentric rings in MIMO design along with proposed isolation enhancement technique is validated using measurements from a prototype.

关键词： Angle diversity complementary split-ring resonator correlation coefficient multiple-input-multiple-output mutual coupling polarization diversity square ring

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Four element half circle shape printed mimo antenna

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MICROWAVE AND OPTICAL TECHNOLOGY LETTERS 2016年第12期58卷 2990-2992页

作者： Hassan, A. T. Sharawi, M. S. King Fahd Univ Petr & Minerals Dept Elect Engn Dhahran 31261 Saudi Arabia

In this work, a four element multiple-input-multiple-output (MIMO) antenna system with half circle shape printed monopole antennas is presented. The antenna elements are designed on an FR4 substrate with dielectric constant 4.3 and dimensions of 110 x 60 x 0.8 mm(3). These antennas are covering part of 4G and WLAN bands with maximum measured gain and efficiency of 3.12 dB and 81.5%, respectively, along with a -10 dB bandwidth of 230 MHz. The coupling between adjacent ports is at least -11 dB without using any technique for isolation enhancement. The MIMO antenna system has good pattern isolation such that the correlation coefficient is calculated using the measured three-dimensional (3D) far field radiation pattern with a maximum value of 0.3 at 2.4 GHz. The proposed design can be used in handheld terminals. (c) 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2990-2992, 2016

关键词： multiple-input-multiple-output printed monopole correlation coefficient (3D) far field radiation pattern 4G

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Estimation of continuous flat fading MIMO channels

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2002年第4期1卷 549-553页

作者： Sun, QF Cox, DC Huang, HC Lozano, A Atheros Commun Sunnyvale CA 94085 USA Stanford Univ Dept Elect Engn Stanford CA 94305 USA Lucent Bell Labs Crawford Hill NJ 07733 USA

multiple-input-multiple-output (MIMO) systems can provide high data rate wireless services in a rich scattering environment. In this paper, we study one of the proposals for MIMO systems, the Bell Labs Layered Space-Time (BLAST) architecture. Channel estimation using training sequences is required for coherent detection in BLAST. We apply the maximum-likelihood channel estimator and the optimal training sequences for block flat fading channels to continuous flat fading channels and analyze the estimation error. The optimal training length and training interval that maximize the throughput for a given target bit error-rate are found by computer simulations as functions of the Doppler frequency and the number of antennas.

关键词： Bell Labs layered space-time channel estimation continuous fading multiple-input-multiple-output optimal training parameters training

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Secrecy Enhancement Analysis Against Unknown Eavesdropping in Spatial Modulation

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IEEE COMMUNICATIONS LETTERS 2015年第8期19卷 1351-1354页

作者： Wang, Li Bashar, Shafi Wei, Yaman Li, Ruoguang Beijing Univ Posts & Telecommun Sch Elect Engn Beijing Key Lab Work Safety Intelligent Monitorin Beijing 100876 Peoples R China Yelp Inc San Francisco CA 94105 USA

In multiple-input-multiple-output (MIMO) wireless communications, spatial modulation (SM) has recently emerged as a new transmission method. This letter explores the physical-layer security in typical SM systems. We present a secrecy rate analysis for multiple antenna destination and eavesdroppers receivers. Targeting against passive eavesdroppers in unknown locations, we study the efficacy of active security measure through joint signal and jamming transmission without the typical requirement of eavesdropper channel information. We demonstrate the secrecy rate and transmission power tradeoff in active source jamming by providing numerical results on achieved secrecy rate and the bit error rate (BER) at different receivers.

关键词： multiple-input-multiple-output eavesdropping spatial modulation secrecy rate

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Low-Complexity Signal Vector Based Detection Algorithm for Spatial Modulation

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INTERNATIONAL JOURNAL OF FUTURE GENERATION COMMUNICATION AND NETWORKING 2016年第2期9卷 257-268页

作者： Jiang, Yang Wen, Jiejun Wang, Yuanlu Li, Yibo Chongqing Univ Sch Commun Engn Chongqing 630044 Peoples R China

In this paper, signal vector based detection (SVD) algorithm for spatial modulation (SM) is modified to achieve a near maximum-likelihood (ML) performance and reduces the complexity compared to ML. First, the proposed low-complexity SVD (LC-SVD) algorithm orders the antenna index list based on the angle between the received vector y and the channel vector h(j), and then it estimates symbol by compensating the channel attenuation with transmitting antenna index list. We can trade-off between the performance and the complexity by changing the number of the candidate transmitting antennas. The theoretical analysis and simulation results show that the LC-SVD algorithm can achieve a near-ML performance with lower complexity.

关键词： Spatial modulation Complexity SVD multiple-input-multiple-output

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An Origami Based Capacity Resilient and Reconfigurable MIMO System

An Origami Based Capacity Resilient and Reconfigurable MIMO ...

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International Symposium of Applied-Computational-Electromagnetics-Society (ACES)

作者： Russo, Nicholas E. Zekios, Constantinos L. Georgakopoulos, Stavros, V Florida Int Univ Dept Elect & Comp Engn Miami FL 33199 USA

ISBN: (纸本)9780996007887

In this work, the ability of a physically reconfigurable, linear uniform, MIMO antenna with variable interelement spacing to achieve maximum capacity is demonstrated for a variety of propagation scenarios. Propagation scenarios are differentiated based upon the angle of incidence. An example situation with two transmit and two receive antennas is analyzed. It is shown that the maximum capacity is achieved by appropriately selecting the inter-element spacing for different propagation scenarios. Demonstrating the resilience of this reconfigurable antenna, high throughput communications are allowed to be reliably achieved.

关键词： multiple-input-multiple-output MIMO reconfigurable Origami structure

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Analytical Results for the Performance of MIMO Systems in Frequency Selective Fading Channels

Analytical Results for the Performance of MIMO Systems in Fr...

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IEEE 72nd Vehicular Technology Conference Fall 2010

作者： Xu, Rongtao Chen, Jiann-Mou Su, Zhou Beijing Jiaotong Univ State Key Lab Rail Traff Control & Safety Beijing Peoples R China Hwa Hsia Inst Technol Dept Assets & Property Management Taipei Taiwan Waseda Univ Fac Sci & Engn Shinjyu Ku Tokyo Japan

ISBN: (纸本)9781424435746

The performance of spatial multiplexing-based multiple-input multiple output (MIMO) systems using zero forcing (ZF) detector in frequency selective fading channels is analyzed in this paper. The approximation of a linear combination of Wishart matrices is used to derive the probability density function (p.d.f.) of output signal-to-noise ratio (SNR) expression. Analytical error rate expressions for the system are obtained with the assumption that inter-path interference is omitted. Simulations are carried out to evaluate the analytical results. We relate the diversity order of frequency selective fading channels with the multipath power delay profile.

关键词： multiple-input-multiple-output zero-forcing Wishart matrix frequency selective

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A Simultaneous-Alternate Relaying Scheme for the Two-Cell Two-Hop MIMO X Channel With Shared Relays 3

A Simultaneous-Alternate Relaying Scheme for the Two-Cell Tw...

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3rd IEEE International Conference on Computer and Communications (ICCC)

作者： Jin, Jin Gao, Xiang-Chuan Zhengzhou Univ Sch Informat Engn Zhengzhou Henan Peoples R China

ISBN: (纸本)9781509063529

We consider a two-cell two-hop X channel, where each of the two base stations sends an independent message to each of the two mobile stations via two half-duplex relays. It is assumed that each of the base stations and mobile stations has M antennas while each relay is equipped with N antennas. In this channel, the previously known upper bounds on the degrees of freedom (DoF) are characterized based on the alternate relaying and simultaneous relaying, respectively. In this paper, we establish a new DoF upper bound based on the simultaneous-alternate relaying, which provides superior DoF gain over the derived upper bounds of the alternate relaying and simultaneous relaying for the case of 3/2 < N/M < 8/3. Furthermore, an achievable scheme is provided to reach the DoF upper bound of the simultaneous-alternate relaying.

关键词： degrees of freedom interference cancellation X channel relays multiple-input-multiple-output

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