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2008 IEEE International Conference Neural Networks and signal {1., ICNNSP

作者： Wanli, Lv Yutang, Guo Jixin, Ma Bin, Luo Key Lab. of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei 230039 China Computer Department Anhui Institute of Education Hefei 230061 China School of Computing and Mathematical Sciences University of Greenwich United Kingdom

ISBN: (纸本)9781424423118

In this paper, a novel watermarking scheme based on relationship of Tchebichef Moments is proposed. Firstly, the image is divided into blocks;then the Tchebichef moment's relationship of each block is computed, which is computed rapidly with the help of the look-up-table;finally, the Tchebichef moments of each block are modified to embed watermark. The watermark extraction is the reverse procedure of the watermark embedding and the original image is not necessary in the watermark detection. Experimental results demonstrate that the proposed watermarking technique is robustness to attacks such as JPEG compress, noises, luminance and contrast enhancement and low pass filtering. ©2008 IEEE.

关键词： Low pass filters

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A Novel Tri-band Frequency Selective Surface 2

A Novel Tri-band Frequency Selective Surface

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2020 2nd International Conference on Artificial Intelligence Technologies and Application, ICAITA 2020

作者： Wu, Shenbing Chen, Mingsheng Wang, Chao Wu, Xianliang Key Lab of Ministry of Education of Intelligent Computing and Signal Processing Anhui University Hefei Anhui230601 China School of Electronic Engineering Huainan Normal University Huainan Anhui232001 China

This paper presents a novel tri-band frequency miniaturized frequency selection surface (FSS). The proposed FSS consists of single-node folding and single-node folding bending. The single-layer FSS exhibits three stop bands centered at 2.45, 3.61.and 5.79 GHz, with bandwidths of 0.42, 0.48 and 0.70 GHz, respectively. The proposed FSS has better miniaturization characteristics, and its cell size is 0.1.6 ?×0.1.6 ?. The three stop band frequencies of the FSS can be independently controlled by simply changing the length of the corresponding branch. In addition, the proposed FSS is symmetrical about the center and exhibits good resonance stability in both TE and TM polarization. The prototype of the proposed FSS was fabricated and tested, compared with the simulation results, the FSS showed stable performance. This method provides ideas for designing multiband FSS in the future. © 2020 Published under licence by IOP Publishing Ltd.

关键词： Frequency selective surfaces

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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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201. International Conference on Microwave and Millimeter Wave Technology, ICMMT 201.

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 (1.) grid and using the nature of numerical plane wave in FDTD, an efficient plane wave sources is simulated on 1. 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. © 201. IEEE.

关键词： Wave propagation

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Wideband 1.-port mimo antenna array for 5g metal-frame smartphone applications

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Progress In Electromagnetics Research C 2020年 104卷 229-240页

作者： Liu, Peng Sun, Yufa Liu, Tao Li, Qing Wang, Xuefeng Key Lab of Intelligent Computing & Signal Processing Ministry of Education Anhui University Hefei230601 China

A wideband 1.-port multiple input multiple output (MIMO) antenna array operated below 6 GHz for the fifth generation (5G) metal-frame smartphones is presented and discussed in this paper. The proposed MIMO antenna array element is composed of a microstrip line with a tuning stub and rectangular slot. The size of the rectangular slot is only 1. mm × 2 mm (0.21.λ0 × 0.028λ0, and λ0 is the wavelength with the resonance frequency of 4.2 GHz). U-shaped slots on the substrate are used to reduce the mutual coupling between the antenna elements. At the same time, in order to improve the radiation characteristics of the antenna arrays, narrow slits are etched in the metal-frame. The proposed antenna covers 3.3–5.5 GHz (S1. © 2020, Electromagnetics Academy. All rights reserved.

关键词： Antenna arrays

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Dielectric Resonator Magnetoelectric Dipole Arrays with Low Cross Polarization,Backward Radiation,and Mutual Coupling for MIMO Base Station Applications

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China Communications 2024年第6期21卷 290-304页

作者： Song Simin Da Yiran Qian Bingyi Huang Xiaoyu Chen Xiaoming Li Yingsong Ahmed A.Kishk School of Information and Communications Engineering Xi’an Jiaotong UniversityXi’an 710049China Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education Anhui UniversityHefei 230039China Department of Electrical and Computer Engineering Concordia UniversityMontrealQC H3G 1M8Canada

Dielectric resonator magnetoelectric dipole(DRMED)arrays with enhanced isolation,reduced cross-polarization,and backward radiation are proposed for base station(BS)*** proposed antenna comprises an elevated dielectric resonator antenna(DRA)on a small metal plate above a sizeable common ground *** DRA is designed in its T Eδ1. mode,acting like a magnetic *** surface current excited by the differential probes flowing on the small ground plane is equivalent to an electric *** these two equivalent dipoles are orthogonal,they have the magnetoelectric dipole characteristics with reduced backward ***,the small ground planes can be treated as decoupling structures to provide a neutralization path to cancel the original coupling path.A linearly-polarized 4-element prototype array was verified experimentally in previous ***,a dual-polarized DRMED antenna is presented to construct a 2-element and 4×4 array for BS *** investigate its MIMO performance,sophisticated multi-cell scenario simulations are carried *** using the proposed dualpolarized DRMED array,the cellular system capacityis improved by 1.8.6%compared to a conventional DRA *** significant MIMO system improvement is mainly due to the reduced backward radiation and,therefore,reduced inter-cell *** align well with the simulations.

关键词： backward radiation dielectric resonator antennas(DRAs) isolation magnetoelectric-dipole(ME-dipole)antennas

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A Pilot Allocation Method of Jointing Cell Grouping and Alliance Game in Massive MIMO System

A Pilot Allocation Method of Jointing Cell Grouping and Alli...

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第二届材料科学应用与能源材料国际研讨会

作者： Feiyue Wang Hui Zhi Ziju Huang Key Lab of Computing Intelligent and Signal Processing(Ministry of Education) Anhui University

In order to improve the uplink channel estimation performance and reduce pilot contamination(PC),this paper proposes a pilot allocation method of jointing cell grouping and alliance game(JCG-AG) for massive multiple-input multiple-output(MIMO) cellular *** can be divided into two ***,by properly dividing all cells into different cell-groups,the users in different cell-groups are allocated different orthogonal pilot ***,the users in the same cell-group are further divided into several mutually disjoint *** belonging to different sub-alliances are allocated different pilots,and users belonging to the same sub-alliance reuse the same *** the second step,the alliance formation algorithm is used to suppress *** JCG-AG method takes practical application as the starting point,focuses on the random distribution of users,and uses the idea of alliance *** these make it more flexible and *** demonstrated in the simulation results,the JCG-AG method can greatly mitigate the PC and reduce the average mean square error(MSE) for all channel estimations in the uplink.

关键词： MSE red A Pilot Allocation Method of Jointing Cell Grouping and Alliance Game in Massive MIMO System

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A new coupled-loop antenna for eight-band LTE/WWAN operation in ultra-thin laptop computer

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Progress In Electromagnetics Research C 2013年 42卷 229-238页

作者： Zhu, Xianbin Sun, Yufa Key Lab of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei 230039 China

A new structure of coupled-fed loop antenna con- nected with two branch radiators for eight-band LTE/WWAN (LTE700/GSM850/900/1.00/1.00/UMTS/LTE2300/2500) operation in the ultra-thin laptop computer is presented. The two branch strips of the antenna are e±cient radiators and contributing multi-resonant modes to greatly enhance the bandwidth of the antenna. The proposed antenna on the top shielding metal wall of the laptop display, with a planar and compact size of 1.:5 × 70 × 0:8mm3, is suitable to be embedded inside the casing of the laptop computer. The proposed antenna is fabricated and tested, and good radiation performances are obtained. Compared with the existing published antennas, the volume of the planar antenna is quite small.

关键词： Laptop computers

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A logarithmic backoff algorithm based on dynamic contention window adjustment for IEEE 802.1. DCF

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Journal of Computational Information Systems 2014年第17期10卷 7609-7617页

作者： Xu, Lei Wang, Li Xun, Huili H., Zhang X., Li Key Lab. of Intelligent Computing and Signal Processing of Ministry of Education Anhui University Hefei China

IEEE 802.1. is a protocol standard widely used in wireless local area network (WLAN). For the distributed coordination function (DCF) of IEEE 802.1. MAC layer, the binary exponential backoff (BEB) algorithm has the defect of poor access fairness. To address this issue, the design criteria of backoff algorithm is generalized from the analysis of the key performance parameters of DCF, and then a logarithmic backoff (LB) algorithm based on dynamic contention window (CW) adjustment is proposed. The algorithm dynamically adjusts the initial value of CW and the backoff size of the CW by using the logarithmic function that takes the number of network competing nodes as the variable. Simulation results show that compared with the BEB algorithm, the LB algorithm can effectively improve the fairness performance and the throughput performance, and also reduce network delay.

关键词： IEEE Standards

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Design of reconfigurable monopole antenna with switchable dual band-notches for UWB applications

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Progress In Electromagnetics Research C 2019年 96卷 97-107页

作者： Li, Ji Sun, Yufa Key Lab of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei230601 China

A reconfigurable antenna with on-demand single-band or dual-band rejection capability for ultra-wideband (UWB) applications is presented. A modified monopole structure is integrated with a U-shaped slot and an open-ended slot to realize band-rejection. The antenna operates in four modes: A full UWB (3.1.1..6 GHz) coverage antenna, a UWB antenna with a single-band WiMax or wide local area network (WLAN) rejection, and a UWB antenna with dual-band WiMax/WLAN rejection. On-demand single and dual-band rejections are implemented by controlling two slots using two PIN diodes. Thus, the adopted control technique is quite easy and requires low operating power. Details of the design process and reconfiguration mechanism are presented. The band-rejection performance is explained by return loss and surface current distribution at single-band mode. A prototype is built on a Rogers substrate and tested to validate the performances. The antenna exhibits stable radiation characteristics and almost flat gain responses across the whole band, while significantly gain reduction is achieved at the rejected bands. Therefore, this antenna is suitable for high-performance UWB systems in WiMax/WLAN dense environments with the aim to improve signal quality, system capacity, and communication efficiency. © 201., Electromagnetics Academy. All rights reserved.

关键词： Monopole antennas

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A broadband dual-polarized magneto-electric dipole antenna for 2G/3G/LTE/WiMAX applications

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Progress In Electromagnetics Research C 2017年 73卷 127-136页

作者： Li, Zuming Sun, Yufa Yang, Ming Wu, Zhifeng Tang, Peiquan Key Lab of Intelligent Computing & Signal Processing Ministry of Education Anhui University Hefei230601 China

A novel broadband dual-polarized magneto-electric (ME) dipole antenna is proposed for 2G/3G/LTE/WiMAX applications. The proposed antenna has stair-shaped feeding strips to impart a wide impedance bandwidth to it and a rectangular box-shaped reflector to enhance its stability in radiation patterns and high gain over the operating frequencies. The measured results show that a common impedance bandwidth is 80% with standing-wave ratio (SWR) ≤ 1.5 from 1.68 to 3.92 GHz, and port-to-port isolation larger than 25 dB within the bandwidth. The measured antenna gains vary from 9.2 to 1. dBi and from 9.2 to 1..8 dBi for port 1.and port 2, respectively. The antenna has nearly symmetrical radiation patterns with low back-lobe radiation both in horizontal and vertical planes, and broadside radiation patterns with narrow beam can also be obtained. © 201., Electromagnetics Academy. All rights reserved.

关键词： Dipole antennas

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