检索结果-内蒙古大学图书馆

International Conference on Transparent Optical Networks

作者： Mohamed Al-Nahhal Hossam M. Kasem Tawfik Ismail Mohamed E. Nasr Tanta University Tanta EG Faculty of Engineering Tanta University Egypt National Institute of Laser Enhanced Science Cairo University Egypt

This paper presents an improvement for a bit error rate (BER) performance in a free-space optical communication system over log-normal fading channel and misalignment effect, by using single-input multiple-output (SIMO) technique with maximal ratio combining. Differential phase shift keying with subcarrier intensity modulation is applied. The BER closed-form expression is obtained and compared to integration numerically solution. The simulation results show that the BER performance is improved by using SIMO system.

关键词： Free space optical Log-normal fading Misalignment Differential phase shift keying Bit error rate single-input multiple-output

来源：评论

学校读者我要写书评

暂无评论

High-Efficiency Step-Down Converter Via Coupled Inductor 8

High-Efficiency Step-Down Converter Via Coupled Inductor

引用

8th IEEE International Power Electronics and Motion Control Conference (IPEMC-ECCE Asia)

作者： Wai, Rong-Jong Liaw, Jun-Jie Natl Taiwan Univ Sci & Technol Dept Elect & Comp Engn Taipei 106 Taiwan Yuan Ze Univ Dept Elect Engn Chungli 320 Taiwan

ISBN: (纸本)9781509012107

In this study, a high-efficiency single-input multiple-output (SIMO) step-down converter is designed. The coupled-inductor-based SIMO step-down converter utilizes two power switches with the properties of voltage clamping for the middle-voltage switch, and soft switching for all power switches due to the appropriately choice of the corresponding device specifications. As a result, the leakage inductor energy of the coupled inductor can be recycled, and the voltage spikes on power switches can be alleviated. Moreover, the switching losses can be significantly decreased because of all power switches with zero-voltage-switching (ZVS) features. Therefore, the objectives of high-efficiency power conversion, high step-down ratio, and various output voltage with different levels can be obtained. The effectiveness of the proposed SIMO step-down converter is verified by experimental results of a converter prototype in practical applications.

关键词： high efficiency single-input multiple-output step-down converter zero voltage switching

来源：评论

学校读者我要写书评

暂无评论

BER Analysis for BPSK Based SIM-FSO Communication System Over Strong Atmospheric Turbulence with Spatial Diversity and Pointing Errors

引用

WIRELESS PERSONAL COMMUNICATIONS 2015年第3期81卷 1143-1157页

作者： Prabu, K. Kumar, D. Sriram Natl Inst Technol Dept Elect & Commun Engn Tiruchirappalli 620015 Tamil Nadu India

Free space optical communication (FSO) has much attention in recent years for the applications viz. inter-satellite, deep space communications, inter and intra chip communications. The performance of FSO systems sternly suffers from atmospheric turbulence due to the random nature of weather conditions. Spatial diversity is an emerging technique for improving the performance of the system over strong atmospheric turbulences. In this paper, the error rate performance of binary phase shift keying based subcarrier intensity modulated free space optical (SIM-FSO) communication system over gamma-gamma channel with pointing errors is investigated. Novel closed-form analytical expressions are derived for the average bit error rate of single-input multiple-output FSO (SIMO-FSO) system with various combining schemes. The error rate performance of SISO and SIMO-FSO systems are compared in terms of 2D and 3D plots.

关键词： Free space optics Pointing errors Strong atmospheric turbulence Bit error rate single-input multiple-output

来源：评论

学校读者我要写书评

暂无评论

Secrecy Performance Analysis for SIMO Simultaneous Wireless Information and Power Transfer Systems

引用

IEEE TRANSACTIONS ON COMMUNICATIONS 2015年第9期63卷 3423-3433页

作者： Pan, Gaofeng Tang, Chaoqing Li, Tingting Chen, Yunfei Southwest Univ Sch Elect & Informat Engn Chongqing 400715 Peoples R China Southwest Univ Sch Math & Stat Chongqing 400715 Peoples R China Univ Warwick Sch Engn Coventry CV4 7AL W Midlands England

In this paper, a single-input multiple-output (SIMO) simultaneous wireless information and power transfer system consisting of one base station, one desired information receiver and N (N > 1) energy-harvesting receivers is considered. Each link in the considered system suffers not only from small-scale fading but also path-loss. In particular, we focus on the physical layer security performance including secrecy outage and secrecy capacity in the presence of eavesdroppers. We derive the closed-form analytical expression for the exact and the asymptotic secrecy outage probability while considering each eavesdropping link experiences independent but not necessarily identical Rayleigh fading. The closed-form analytical expression for the average secrecy capacity has also been derived for the case that all eavesdropping links experience independent and identical Rayleigh fading. Numerical and Monte Carlo simulation results are presented to verify our derived analytical models.

关键词： Secure communication simultaneous wireless information and power transfer single-input multiple-output secrecy capacity secrecy outage probability

来源：评论

学校读者我要写书评

暂无评论

Bit error rate analysis of free-space optical system with spatial diversity over strong atmospheric turbulence channel with pointing errors

引用

OPTICAL ENGINEERING 2014年第12期53卷 1-6页

作者： Krishnan, Prabu Kumar, D. Sriram Natl Inst Technol Dept Elect & Commun Engn Tiruchirappalli 620015 Tamil Nadu India

Free-space optical communication (FSO) is emerging as a captivating alternative to work out the hindrances in the connectivity problems. It can be used for transmitting signals over common lands and properties that the sender or receiver may not own. The performance of an FSO system depends on the random environmental conditions. The bit error rate (BER) performance of differential phase shift keying FSO system is investigated. A distributed strong atmospheric turbulence channel with pointing error is considered for the BER analysis. Here, the system models are developed for single-input, single-output-FSO (SISO-FSO) and single-input, multiple-output-FSO (SIMO-FSO) systems. The closed-form mathematical expressions are derived for the average BER with various combining schemes in terms of the Meijer's G function. (C) 2014 Society of Photo-Optical Instrumentation Engineers (SPIE)

关键词： free-space optics differential phase shift keying strong atmospheric turbulence single-input multiple-output

来源：评论

学校读者我要写书评

暂无评论

BER analysis of DPSK-SIM over MIMO free space optical links with misalignment

引用

OPTIK 2014年第18期125卷 5176-5180页

作者： Prabu, K. Kumar, D. Sriram NIT Dept Elect & Commun Engn Tiruchirappalli 620015 Tamil Nadu India

Free-space optics (FSO) is a safe, license-free, high speed and high-bandwidth cordless technique for broadcasting signals at the same speed as fiber optics. But the main drawback of FSO is the dissolution of the signals due to atmospheric turbulence and thus degrading the link performance. So, to enhance the bit error rate (BER) performance, spatial diversity is employed over the FSO links for single-input multiple-output FSO (SIMO-FSO) systems. In this paper, we analyze the BER performance of SIMO-FSO links with spatial diversity and multiple-input multiple-output FSO (MIMO-FSO) systems over gamma-gamma atmospheric turbulence fading channel with misalignment (pointing errors). The closed form expressions are derived for the same with various combining schemes in terms of the Meijer G function and also evaluate the results with 2D and 3D graphs. (C) 2014 Elsevier GmbH. All rights reserved.

关键词： Free space optics Differential phase shift keying subcarrier intensity modulation Strong atmospheric turbulence Pointing errors single-input multiple-output multiple-input multiple-output

来源：评论

学校读者我要写书评

暂无评论

Maximum SNR Relaying Strategies for AF SIMO Wireless Relay Networks 79

Maximum SNR Relaying Strategies for AF SIMO Wireless Relay N...

引用

IEEE 79th Vehicular Technology Conference (VTC-Spring)

作者： Lee, Kanghee Yang, Jie Kwon, Hyuck M. Sawan, Edwin M. Park, Hyuncheol Wichita State Univ Dept Elect Engn & Comp Sci Wichita KS 67260 USA Korea Adv Inst Sci & Technol Dept Elect Engn Daejeon 305701 South Korea

ISBN: (纸本)9781479944828

This paper addresses optimum nondiagonal and diagonal amplifying relay matrices for the amplify-and-forward (AF) wireless relay networks. single-input multiple-output (SIMO) nondistributed and distributed relaying system strategies with the relay power constraint are applied, based on the signal-to-noise ratio (SNR) criterion. By adopting the optimum amplifying relay matrices derived, the SNRs at the destinations are analytically and numerically investigated in order to evaluate the proposed system. In particular, using the SNR values, it can be predicted which scheme would yield a better system performance than the others.

关键词： Amplify-and-forward power constraint single-input multiple-output zero forcing

来源：评论

学校读者我要写书评

暂无评论

Maximum SNR Relaying Strategies for AF SIMO Wireless Relay Networks

Maximum SNR Relaying Strategies for AF SIMO Wireless Relay N...

引用

IEEE Vehicular Technology Conference

作者： Kanghee Lee Jie Yang Hyuck M. Kwon Edwin M. Sawan Hyuncheol Park Department of Electrical Engineering and Computer Science Wichita State University Department of Electrical Engineering Korea Advanced Institute of Science and Technology

ISBN: (纸本)9781479944811

关键词： Amplify-and-forward Power constraint single-input multiple-output Zero forcing

来源：评论

学校读者我要写书评

暂无评论

Adaptive Bayesian space-time equalisation for multiple receive-antenna assisted single-input multiple-output systems

引用

DIGITAL SIGNAL PROCESSING 2008年第4期18卷 622-634页

作者： Chen, S. Liu, S. Hanzo, L. Univ Southampton Sch Elect & Comp Sci Southampton SO17 1BJ Hants England

This contribution considers nonlinear space-time equalisation (STE) for multiple receive-antenna induced single-input multiple-output (SIMO) systems. By exploiting the inherent symmetry of the underlying optimal Bayesian STE solution, a novel symmetric radial basis function (RBF) based STE scheme is proposed, which is capable of approaching the optimal Bayesian equalisation performance. Adaptive implementation of this symmetric RBF (SRBF) based STE can be achieved conveniently by estimating the SIMO channels using the least mean square channel estimator and computing the optimal RBF centres from the resulting SIMO channel matrix estimate. Simulation results also demonstrate that the performance of this SRBF based STE is robust with respect to the choice of the RBF variance value. The proposed adaptive solution is then extended to the space-time decision feedback equalisation (ST-DFE) structure. (C) 2007 Elsevier Inc. All rights reserved.

关键词： multiple antennas single-input multiple-output space-time equaliser space-time decision feedback equaliser Bayesian equaliser symmetric radial basis function network

来源：评论

学校读者我要写书评

暂无评论

Equalisation of SIMO-OFDM systems with insufficient cyclic prefix in doubly selective channels

引用

IET COMMUNICATIONS 2009年第12期3卷 1870-1882页

作者： Beheshti, M. Omidi, M. J. Doost-Hoseini, A. M. IUT Dept Elect & Comp Engn ECE Esfahan Iran

Time variations of a doubly selective wireless channel and insufficient cyclic prefix (CP) length of an orthogonal frequency division multiplexing (OFDM) transmission system cause intercarrier interference (ICI) and interblock interference (IBI) as significant limitations. This paper investigates the problem of joint ICI and IBI mitigation in single-input multiple-output OFDM (SIMO-OFDM) systems. It is assumed, unlike most existing literature, that the channel delay spread is larger than the CP, and also the channel varies on each OFDM block. First, doubly selective channel is modelled using basis expansion model (BEM) and a closed-form expression for signal-to-interference-plus-noise ratio (SINR) is derived. Then, a time-domain equaliser is developed, which maximises the SINR for all subcarriers. Moreover, a frequency-domain equalisation approach is proposed which is based on the MSE minimisation per tone. A low-complexity implementation of the pertone equaliser is also derived. An important feature of the proposed equalisers is that no bandwidth expansion or redundancy insertion is required except for the CP. Finally, complexity comparison and simulation results over Rayleigh fading channel are provided to illustrate the effectiveness of the proposed approaches. Since both equalisers are designed in the frequency domain, they provide significant interference cancellation.

关键词： Electromagnetic compatibility and interference ICI signal-to-interference-plus-noise ratio minimisation Optimisation techniques interblock interference insufficient cyclic prefix SIMO-OFDM system Modulation and coding methods single-input multiple-output basis expansion model orthogonal frequency division multiplexing wireless channels doubly selective wireless channel OFDM modulation time-domain analysis time-domain equaliser intercarrier interference Mathematical analysis channel delay spread equalisers IBI time variation frequency-domain analysis bandwidth expansion Radio links and equipment Rayleigh fading channel frequency-domain equalisation approach

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：