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Analysis of asymptotic approximation SER for Alamouti code transmission protocol in cooperative communication networks

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Journal of Information and Computational Science 2011年第14期8卷 3003-3010页

作者： Xu, Lei Zhang, Hongwei Li, Xiaohui Wu, Xianliang Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei 230039 China

Some time division multiple access (TDMA) wireless cooperative relay protocols have recently been developed. The works about their symbol error rate (SER) performance, however, are limited to SER upper bounds or SER formulas with complex structures. For SER performance analysis of wireless cooperative communication system with multiple relays, the tightly approximated SER formula, which has a simple structure, is gotten by using the simplified calculation method of moment generating function (MGF). In high signal-to-noise ratio (SNR) conditions, this formula not only can describe the SER performance accurately, but also is convenient for the research of network topology and optimum power allocation. 1548-7741/Copyright © 2011 Binary Information Press December 2011.

关键词： Cooperative communication

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Analysis of asymptotic approximation SER for TDMA relay protocol in cooperative communication networks

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Journal of Information and Computational Science 2011年第12期8卷 2367-2374页

作者： Xu, Lei Zhang, Hongwei Li, Xiaohui Wu, Xianliang Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei 230039 China

Some Time Division Multiple Access (TDMA) wireless cooperative relay protocols and their Symbol Error Rate (SER) performance have recently been developed. These works, however, are limited to SER upper bounds or SER formulas with complex structures. For SER performance analysis of wireless cooperative communication system with multiple relays, the tightly approximated SER formula, which has a simple structure, is gotten by using the simplified calculation method of Moment Generating Function (MGF). In high signal-to-noise Ratio (SNR) conditions, this formula not only can describe the SER performance accurately, but also is convenient for the research of network topology and optimum power allocation. 1548-7741/Copyright © 2011 Binary Information Press.

关键词： Cooperative communication

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Through-wall synthetic aperture radar based on finite beamwidth processing

Through-wall synthetic aperture radar based on finite beamwi...

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3rd Microwaves, Radar and Remote Sensing Symposium, MRRS-2011

作者： Zhu, Jiabing Hong, Yi Tao, Liang East China Research Institute of Electronic Engineering Hefei Anhui China Education Ministry Key Lab. of Intelligent Computing and Signal Processing Anhui University China

ISBN: (纸本)9781424496440

Standard backprojection technique is used in typical through-wall synthetic aperture radar (TWSAR) image, it implicitly assumes infinite beamwidth, whereby the entire target area is illuminated and returns are collected from all points in the imaging grid, and this decreases the efficiency of the algorithm by summing over unnecessary grid points. In order to eliminate the disadvantage, the time-domain backprojection method based on finite beamwidth processing is proposed in the paper. The processing method is designed to be more physically realistic by accounting for the actual antenna pattern. Simulation results show that depending on the width of the effective beam, the number of processing loops can be reduced by up to 50%, while still maintaining good image quality in terms of the reconstructed target response. © 2011 IEEE.

关键词： processing

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A split-operator method to simulate the left hand materials

A split-operator method to simulate the left hand materials

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2011 Cross Strait Quad-Regional Radio Science and Wireless Technology Conference, CSQRWC 2011

作者： Ren, Xin-Gang Huang, Zhi-Xiang Wu, Xian-Liang Lu, Si-Long Mei, Yi-Cai Du, Hong-Mei Wu, Lei Key Lab. of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei China Department of Physics and Electronic Engineering Hefei Normal University Hefei China

ISBN: (纸本)9781424497904

The finite difference time domain (FDTD) is a powerful method in electromagnetic simulation and also widely used in research of the metamaterials recently. In this paper a novel FDTD method based on split operator is proposed to simulate the left hand materials, and the lossless Drude dispersive model is taken into account in the proposed scheme. The split perfectly matched layers (SPML) are used to absorb outgoing wave and terminate the computational domain. Focusing and refocusing of the electromagnetic wave in target detection by using the perfect lens is validated, and the inverse Snell effect is also demonstrated. © 2011 IEEE.

关键词： Electromagnetic simulation

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Perfect plane wave injection into 3D FDTD (2, 4) scheme

Perfect plane wave injection into 3D FDTD (2, 4) scheme

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2011 Cross Strait Quad-Regional Radio Science and Wireless Technology Conference, CSQRWC 2011

作者： Wang, Hui Huang, Zhi-Xiang Wu, Xian-Liang Wu, Lei Key Lab. of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei China Department of Physics and Electronic Engineering Hefei Normal University Hefei China

ISBN: (纸本)9781424497904

In the paper, the authors derive the method of splitting plane wave FDTD (SP-FDTD) method for initiation of plane wave sources in the total-field and scattered-field (TF/SF) formulation of 3D FDTD (2, 4) scheme. By splitting the fields on 1D auxiliary grids, the identical dispersion relation can be obtained between the 1D auxiliary grids and the 3D grids, which is also proved to be using the nature of plane wave. Using 1D auxiliary grids for introducing a plane wave, a perfect plane wave injection can be achieved at any angle forming an integer grid cell ratio. Numerical simulations also indicate the efficiency and validity of the method for FDTD (2, 4) scheme and the leakage error on the order of -300dB for double precision. © 2011 IEEE.

关键词： Numerical methods

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Fusion of multi-polarimetric SAR images using directionlets transform

Fusion of multi-polarimetric SAR images using directionlets ...

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International Conference on Multimedia Technology

作者： Dexiang Zhang Qingwei Gao Xiaopei Wu Yixiang Lu Key Laboratory of Intelligent Computing and Signal Processing of Ministry of Education Anhui University Hefei China

ISBN: (纸本)9781612847719

An efficient SAR image fusion algorithm for multi-polarimetric images based on Directionlets transform is proposed. Directionlets transform is a new lattice-based multi scale analysis anisotropic multi-directional wavelet transform. Firstly, several polarimetric images can be decomposed into low frequency coefficients and high-frequency coefficients with multi scales and multi-directions using the Directionlets transform. For the low-frequency coefficients, the average fusion method is used. For the each directional high frequency sub-band coefficients, the directive contrast and the larger value of region variance information measurement is used to select the better coefficients for fusion. At last the fused image can be obtained by utilizing inverse transform for fused Directionlets coefficients. Experimental results show that compared with traditional algorithm, the proposed algorithm can get better visual effect and the significant information of original image like textures and contour details is well maintained.

关键词： Wavelet transforms Image fusion Speckle Lattices Filter banks

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Optimum relay location in cooperative communication networks with single DF relay

Optimum relay location in cooperative communication networks...

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IEEE International Conference on Computer Science and Automation Engineering (CSAE)

作者： Lei Xu Hong-wei Zhang Xiao-hui Li Xian-liang Wu The Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei China

In wireless communication, the cooperative communications technology has been concern because of its advantages of spatial diversity. In particular, cooperative communication with a single relay is a simple, practical technology for wireless sensor networks. In this paper, we analyze several simple network topologies. Under the condition of equal power allocating, the optimum relay locations are respectively determined by using symbol error rate (SER) formula. And these types of topologies are compared, the analysis results show that, Linear network topology has the best system performance, the system performance of isosceles triangle topology is better than that of equilateral triangle topology.

关键词： Topology Relays Bit error rate Network topology Wireless sensor networks Graphics IEEE Press

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Design and Implementation of Multimedia Control System Based on Bluetooth and Electrooculogram (EOG)

Design and Implementation of Multimedia Control System Based...

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International Conference on Bioinformatics and Biomedical Engineering (ICBBE)

作者： Lian Li XiaoPei Wu Key Laboratory of Intelligent Computing & Signal Processing Ministry of Education Anhui University HeFei China

Nowadays, the Human Computer Interaction (HCI) developments improve the research of EOG. In this paper, A new EOG-based HCI system for multimedia control is designed and implemented. A special headset named Mindset is used to detect the EOG pulses generated by blinking, and then transmit them wirelessly via Bluetooth to PC. Three modules are contained in the system, which are the wireless communication module, EOG recognition module and the multimedia control module, respectively. The system can be used as an assistant for the disable persons, also can be used for amusement among normal people. It is feasible to put the system into practical use due to its security and convenience.

关键词： Electrooculography Bluetooth Multimedia communication Wireless communication Software Human computer interaction Electrodes

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Inverse system internal model control of DIFG wind power generator system based on matrix converter

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Taiyangneng Xuebao/Acta Energiae Solaris Sinica 2012年第11期33卷 1983-1991页

作者： Chen, Caixue Xie, Yunxiang Ma, Xueliang Key Laboratory of Intelligent Computing and Information Processing of Ministry of Education Xiangtan University Xiangtan 411105 China School of Electric Power South China University of Technology Guangzhou 510641 China Guangdong MingYang Wind Power Industry Group Co. Ltd Zhongshan 528437 China

Aim to solve the poor dynamic performance and the low disturbance resistance of PI power decoupling controller for DFIG power generator system based on matrix converter, this paper propose a nonlinear control algorithm for the AC-excitation DFIG system. First, we establish the mathematical model of the DFIG, based on the model, use the inverse system theory and deduce the inverse model, add the inverse model in series to the front of the original system model, develop the whole system to a pseudo linear system. Consider the system performance influenced by the parameters of the linearized model, we use the predictive control to improve the robustness. The simulation results show that the control strategy has fast response and good dynamic performance. The off-grid and cut-grid experimental data validate that under sub-synchronous or super-synchronous state, the stator voltage and frequency can maintain stability and achieve variable speed constant frequency operation.

关键词： Model predictive control

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A Novel Framework for Concept Detection on Large Scale Video Database and Feature Pool

A Novel Framework for Concept Detection on Large Scale Video...

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2011中国人工生命与智能机器人会议

作者： LV Gang ZHENG Cheng Key Laboratory of Network and Intelligent Information Processing Hefei University Hefei Key of Intelligent Computing & Signal Processing Ministry of EducationAnhui University Hefei

Large-scale semantic concept detection from large video database suffers from the large variations among different semantic concepts as well as their corresponding effective low-level features. In this paper, we propose a novel framework to deal with this obstacle. The proposed framework consists of four major components: feature pool construction, pre-filtering, modeling, and classification. First, a large low-level feature pool is constructed, from which a specific set of features are selected for the latter steps automatically or semi-automatically. Then, to deal with the unbalance problem in training set, a pre-filtering classifier is generated, which aim at achieving a high recall rate and a certain precision rate nearly 50％ for a certain concept. Thereafter, from the pre-filtered training samples, a SVM classifier is built based on the selected features in the feature pool. After that, the SVM classifier is applied to classification of semantic concept. This framework is flexible and extensible in terms of adding new features into the feature pool, introducing human interactions on selecting features, building models for new concepts and adopting active learning.

关键词： Semantic Concept Detection Feature Pool Pre-filtering User-defined Concepts

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