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Spectral matching algorithm based on nonsubsampled contourlet transform and scale-invariant feature transform

Journal of Systems Engineering and Electronics 2012年第3期23卷 453-459页

作者： Dong Liang Pu Yan Ming Zhu Yizheng Fan Kui Wang Key Lab of Intelligent Computing ＆ Signal Processing Ministry of Education Anhui University Hefei 230039 E R. China School of Electronics and Information Engineering Anhui University Hefei 230039 P. R. China School of Mathematics and Computation Sciences Anhui University Hefei 230039 P. R. China

A new spectral matching algorithm is proposed by us- ing nonsubsampled contourlet transform and scale-invariant fea- ture transform. The nonsubsampled contourlet transform is used to decompose an image into a low frequency image and several high frequency images, and the scale-invariant feature transform is employed to extract feature points from the low frequency im- age. A proximity matrix is constructed for the feature points of two related images. By singular value decomposition of the proximity matrix, a matching matrix （or matching result） reflecting the match- ing degree among feature points is obtained. Experimental results indicate that the proposed algorithm can reduce time complexity and possess a higher accuracy.

关键词： point pattern matching nonsubsampled contourlet transform scale-invariant feature transform spectral algorithm.

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Perfect plane wave injection for symplectic finite-difference time-domain scheme

Perfect plane wave injection for symplectic finite-differenc...

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2012 International Conference on Microwave and Millimeter Wave Technology, ICMMT 2012

作者： Wang, Hui Huang, Zhi-Xiang Wu, Xian-Liang Wu, Bo Shen, Jing Key Lab. of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei 230039 China Department of Physics and Electronic Engineering Hefei Normal University Hefei 230061 China

ISBN: (纸本)9781467321839

In this paper, the method of splitting plane wave finite-difference time-domain (SP-FDTD) algorithm is presented for the initiation of plane wave sources in symplectic finite-difference time-domain (SFDTD) scheme. By splitting the fields on one-dimensional (1D) grid and using the nature of numerical plane wave in FDTD, an efficient plane wave sources is simulated on 1D grid, and a perfect match is achieved for a plane wave propagating at any angle forming an integer grid cell ratio. Numerical examples show the valid of the proposed method. © 2012 IEEE.

关键词： Wave propagation

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A full-rate wireless cooperative relay transmission scheme with low detection complexity

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Journal of Computational Information Systems 2012年第13期8卷 5279-5285页

作者： Zhang, Hongwei Liu, Yanru Zhang, Ye Li, Xiaohui Key Lab. of Intelligent Computing and Signal Processing of Ministry of Education Anhui University Hefei 230039 China

To achieve low detection complexity and full-rate wireless cooperative transmissions, pre-coding and cyclic delay diversity (CDD) techniques are fully considered and properly combined for a two-path successive relay network with multiple relay nodes in this paper. Firstly, the symbols to be transmitted at source node are encoded with linear complex field coding methods, and then these coded symbols are divided into two data streams. Both streams are transmitted to two groups of relay nodes respectively during two consecutive time slots. After having been amplified and forwarded by relay nodes using CDD ways, all transmit signals are received by the destination node finally. At receiver, only two symbols are needed to be jointly detected in each transmission process, the complexity is low. Simulation results show that the proposed scheme can achieve full-rate cooperative relay transmissions and obtain high diversity gains of the distributed wireless systems. © 2011 by Binary Information Press.

关键词： Orthogonal frequency division multiplexing

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Fast calculation of bistatic RCS for conducting objects using the adaptive cross approximation algorithm

Fast calculation of bistatic RCS for conducting objects usin...

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International Symposium on Antennas Propagation and EM Theory

作者： Lei Chen Yufa Sun Shuaishuai Yang Key Lab. of Intelligent Computing & Signal Processing Ministry of Education Anhui University

ISBN: (纸本)9781467317993

Adaptive cross approximation (ACA) algorithm as a kind of common matrix compression method is often used to analyze the electromagnetic radiation and scattering problems. In the region of far field, the impedance matrix is compressed by ACA method, and the extracted impedance matrix is accelerated filling by equivalent dipole-moment method (EDM). In the area of near field, the method of moments or the equivalent dipole-moment method is applied for filling the impedance matrix. The iterative near field preconditioning technique is used to solve matrix equation, so that fast calculation of radar cross section (RCS) can be achieved. Numerical results show that the computational efficiency is improved significantly via applying the presented method in this paper without sacrificing much accuracy.

关键词： Adaptive cross approximation algorithm Equivalent dipole-moment method Near field preconditioning Radar cross section

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Analysis of electromagnetic characteristics of antenna arrays based on the characteristic basis function method

Analysis of electromagnetic characteristics of antenna array...

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International Symposium on Antennas Propagation and EM Theory

作者： Meng Wu Yufa Sun Guohua Wang Key Lab. of Intelligent Computing & Signal Processing Ministry of Education Anhui University

ISBN: (纸本)9781467317993

The characteristic basis function method (CBFM) is used to analyze the electromagnetic characteristics of antenna arrays in this paper. The original antenna arrays are divided into a number of subdomains and high-level basis functions are constructed for each subdomain through their couplings, the resulting matrix can be largely reduced. The characteristic basis function method not only has high accuracy and computing time is greatly reduced. The numerical results are given to illustrate that the method is accurate and efficient.

关键词： Characteristic basis function method Method of Moments Antenna arrays

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A Design of Temperature and Humidity Remote Monitoring System Based on Wireless Sensor Network Technology

A Design of Temperature and Humidity Remote Monitoring Syste...

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International Conference on Control Engineering and Communication Technology (ICCECT)

作者： Zhiyuan Gao Yingju Jia Hongwei Zhang Xiaohui Li Key Lab of Intelligent Computing and Signal Processing of Ministry of Education Anhui University Hefei China

ISBN: (纸本)9781467344999

In recent years, WSN (Wireless Sensor Network) technology has been developed rapidly, and been widely used in the fields of industry, agriculture, medicine and so on. To solve the low communication rate and short-distance data transmission in the current temperature and humidity monitoring system, this paper designs a temperature and humidity remote monitoring system based on WSN technology. In this system, microprocessor Atmega128L is adopted as the control core of network node, and wireless transceiver module nRF905 is used to realize wireless data transmission. The data of temperature and humidity is sampled by using digital temperature sensor DS18B20 and humidity sensor SHT75 in the system. The proposed network protocol in this paper not only can realize long-rang wireless data transmission, but also can realize self-organizing and manual networking. The results of practical test show that this system has the stable and reliable performance and the advantage of scalability.

关键词： Temperature sensors Wireless sensor networks Humidity Routing Wireless communication Temperature measurement Monitoring

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The structure of the sparse basis function in compressive sensing for fast analysis of wide-angle monostatic scattering problems

The structure of the sparse basis function in compressive se...

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2012 International Conference on Microwave and Millimeter Wave Technology, ICMMT 2012

作者： Du, Hong-Mei Chen, Ming-Sheng Wu, Xian-Liang Key Lab. of Intelligent Computing and Signal Processing Anhui University Ministry of Education Hefei 230029 China Department of Physics and Electronic Engineering Hefei Normal University Hefei 230601 China University of Science and Technology of China Hefei 230026 China

ISBN: (纸本)9781467321839

In the theory of compressive sensing, the selection of the basis functions directly affects the sparse transformation, observation number and reconstruction accuracy. In this paper, we introduce the structure of three sparse basic functions, which are used to analyze the electromagnetic scattering problems over a wide incident angle by the method of moment and compressive sensing. According to the characteristics of the induced current of wide angle, the best basic function is selected. Compared with the DCT, the accuracy of the reconstruction for different shape object are improved and the observation number reduces about 50%. © 2012 IEEE.

关键词： Method of moments

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Rate-embedded differential space-frequency codes based on cyclic delay diversity

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Journal of Computational Information Systems 2012年第1期8卷 151-158页

作者： Zhang, Hongwei Xu, Lei Li, Xiaohui Lu, Lu Key Lab of Intelligent Computing and Signal Processing of Ministry of Education Anhui University Hefei 230039 China Anhui Public Security Department Hefei 230061 China

The conventional differential space-frequency codes (DSFC) based on cyclic delay diversity (CDD) only could achieve the same transmission rate with that of a single transmit antenna system, the spectral efficiency was low. To improve the spectral efficiency in a non-coherent multiple antenna system, the advantage of CDD is considered fully in this paper and then a rate-embedded differential space-frequency coding scheme based on grouped CDD is proposed. In the proposed scheme, all transmit antennas are partitioned into several groups firstly, the conventional cyclic delays are adopted to achieve spatial diversity in each group, those symbols among different groups are transmitted differentially with low rate and high rate message matrices alternately, consequently high rate transmission is obtained. Simulation results verify that, compared with the conventional DSFC based on CDD, the proposed coding scheme can achieve obviously higher transmission rates and better error performances. © 2012 Binary Information Press January 2012.

关键词： Spectrum efficiency

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Numerical dispersion analysis of symplectic and ADI schemes

Numerical dispersion analysis of symplectic and ADI schemes

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International Conference on Microwave and Millimeter Wave Technology Proceedings

作者： Xin-gang Ren Zhi-xiang Huang Xian-liang Wu Si-long Lu Yi-cai Mei Hong-mei Du Hui Wang Jing Shen Key Lab of Intelligent Computing & Signal Processing Ministry of Education Anhui University Hefei China Department of Physics and Electronic Engineering Hefei Normal University Hefei China

In this paper, Maxwell's equations are taken as a Hamiltonian system and then written as Hamiltonian canonical equations by using the functional variation method. The symplectic and ADI schemes, which can be extracted by applying two types of approximation to the time evolution operator, are explicit and implicit scheme in computational electromagnetic simulation, respectively. Since Finite-difference time-domain (FDTD) encounter low accuracy and high dispersion, the more accurate simulation methods can be derived by evaluating the curl operator in the spatial direction with kinds of high order approaches including high order staggered difference, compact finite difference and scaling function approximations. The numerical dispersion of the symplectic and ADI schemes combining with the three high order spatial difference approximations have been analyzed. It has been shown that symplectic scheme combining with compact finite difference and ADI scheme combining with scaling function performance better than other methods. Both schemes can be usefully employed for simulating and solving the large scale electromagnetic problems.

关键词： Dispersion Finite difference methods Function approximation Time domain analysis Maxwell equations Mathematical model

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Fast Calculation of RCS over a Broad Frequency Band Using FDM and AWE technique

Fast Calculation of RCS over a Broad Frequency Band Using FD...

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International Symposium on Antennas Propagation and EM Theory

作者： Tao Sheng Yufa Sun Lingyang Kong Key Lab. of Intelligent Computing & Signal Processing Ministry of Education Anhui University

ISBN: (纸本)9781467317993

The fast dipole method (FDM) in conjunction with the asymptotic waveform evaluation (AWE) technique is presented for fast calculation of radar cross section (RCS) from arbitrarily shaped perfect electric conductor targets over a broad frequency band. The FDM, which is based on the equivalent dipole-moment (EDM) method, is employed to reduce impedance matrix storage and accelerate the matrix-vector multiplications in the solutions of the Taylor coefficients. The application of AWE technique enables fast frequency sweep analysis. The numerical results show that this method greatly increased the computational efficiency without losing accuracy conditions compared with the traditional method of moments (MoM) combined with AWE technique.

关键词： Fast dipole method Equivalent dipole-moment Asymptotic waveform evaluation Radar cross section Method of moments

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