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A novel two-layer compact electromagnetic bandgap (EBG) structure and its applications in microwave circuits

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Science China(Technological Sciences) 2003年第4期46卷 439-447页

作者：杨宁陈志宁王蕴仪 ChiaM.Y.W. State Key Laboratory of Millimeter Waves Southeast University InstituteforInfo comm Research Institute for Info comm Research

This paper presents a novel two-layer electromagnetic bandgap (EBG) structure. The studies on the characteristics of the cell are carried out numerically and experimentally. A lumped-LC equivalent circuit extracted from the numerical simulation is used to model the bandgap characteristics of the proposed EBG structure. The influences of geometric parameters on the operation frequency and equivalent LC parameters are discussed. A meander line high performance bandstop filter and a notch type duplexer are designed and measured. These EBG structures are shown to have potential applications in microwave and RF systems.

关键词： electromagnetic bandgap, microstrip line, filter, duplexer.

Laser Additive Manufacturing of Bio-inspired Metallic Structures

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Chinese Journal of Mechanical Engineering(Additive Manufacturing Frontiers) 2022年第1期1卷 28-38页

作者： Jiankai Yang Dongdong Gu Kaijie Lin Yicha Zhang Meng Guo Luhao Yuan Han Zhang Hongmei Zhang Jiangsu Provincial Engineering Laboratory for Laser Additive Manufacturing of High-Performance Metallic Components College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China icb-comm CNRS UMR 6303UTBM–Universitéde Technologie Belfort-MontbéliardSevenansFrance

High-performance/multifunctional metallic components primarily determine the service performance of equip-ment applied in the aerospace,aviation,and automobile *** have developed structures with specific properties over millions of years of natural evolution,thereby providing inspiration for the design of high-performance structures to satisfy the increasing demands of modern *** the perspective of manufacturing,the ability of conventional processing technologies is inadequate for fabricating these complex structural *** contrast,laser additive manufacturing(AM)is an effective method for fabricating complex metallic bio-inspired structures owing to its layer-by-layer deposition ***,recent devel-opments in the laser AM of bio-inspired cellular,plate,and truss structures,as well as the materials used in laser AM for bio-inspired printing are briefly *** organisms being imitated include butterfly,Norway spruce,mantis shrimp,beetle,and water spider,which expand the diversity of multifunctional structures for laser *** mechanical properties and functions of laser-AM-processed bio-inspired structures are ***,the challenges,possible outcomes,and directions of utilizing laser AM technology to fabricate high-performance/multifunctional metallic bio-inspired structures in the future are outlined.

关键词： Laser additive manufacturing(AM) Laser powder bed fusion(LPBF) Bio-inspired Biomimicry Property Functionality

Software Instrument Based on Software Radio Concept

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Software Instrument Based on Software Radio Concept

Formation and aggregation number of sodium dodecyl sulphonate-polyvinylpyrrolidone aggregates

2001 International Conferences on Info-tech and Info-net

作者： Wang Hua Zou Yi Kuang Jingming Modern comm.Lab Dept.of EE Beijing Institute of Technology

ISBN: (纸本)0780370104;9780780370104

＜正＞In this paper,a virtual instrument based on software radio concept is introduced. The instrument is developed to generate widely existing RF or Baseband signals and demodulate various modulated signals for testing wireless communication systems. By virtue of such an instrument,the performances of typical MODEM（Modulator and Demodulator） can be *** architecture of the instrument is first presented,and then the design ideas and key technologies are *** software based on LABVIEW programming language is developed in order to have an interactive interface and also make the system be operated like an *** prior experiments show that the instrument can meet the general testing requirements of typical MODEM.

关键词： Software radio Software Instrument Modulation and Demodulation Digital Signal Processing

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Chinese Science Bulletin 1997年第21期42卷 1810-1814页

作者： Li, F Li, GZ Xu, GY Wang, HQ Shandong Univ State Educ Comm Key Lab Colloid & Interface Chem Jinan 250100 Peoples R China

THE interaction of surfactants with water-soluble polymers has been an active subject for manyyears. Early investigations were mainly concerned with the effect of synthetic detergents onnatural proteins, such as gel. These studies were motivated by observations of biologicalphenomena involving surfactants and proteins such as the inactivation of bacterial

关键词： aggregation number surface tension fluorescence sodium dodecyl sulphonate polyvinylpyrrolidone.

NEAR OPTIMAL CLUSTER-HEAD SELECTION FOR WIRELESS SENSOR NETWORKS

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Journal of Electronics(China) 2007年第6期24卷 721-725页

作者： Zhu Xiaorong Shen Lianfeng National Mobile comm. Research Lab Southeast University Nanjing 210096 China

Clustering in wireless sensor networks is an effective way to save energy and reuse band- width. To our best knowledge, most of the clustering protocols proposed in literature are of a dynamic type, where cluster heads are selected in each period, followed by cluster formation. In this paper, a new static type clustering method called Hausdorff clustering, which is based on the location of sensor nodes as well as communication efficiency and network connectivity, is proposed. The cluster head, however, is rotated within the cluster by a fuzzy logic algorithm that optimizes the network lifetime. Simulation results show that this approach can significantly increase the lifetime of the sensor network.

关键词：通信技术网络逻辑分析模糊技术

Research and Progress of Service Driven Optical Switching Network in China

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China communications 2008年第1期5卷 9-21页

作者： Wang, Hongxiang Ji, Yuefeng Beijing Univ Posts & Telecommun Sch Telecommun Engn Key Lab Opt Commun & Lightwave Technol Minist EducAcad Comm Beijing Peoples R China

National R&D activities on optical switching networkare introduced. Optical switching network testbedswere established in China including 3T-net andOBS ring and mesh network test-bed with the supportof national '863' ... 详细信息

关键词： optical communications service driven optical network optical circuit switching optical burst switching optical packet switching test-bed

Fast light-path set-up protocol for optical flow switching

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Optoelectronics Letters 2009年第5期5卷 368-371页

作者：曹雪跃张平张振荣何永琪李正斌 State Key Laboratory of Advanced Optical comm. Systems and Networks Peking University School of Computer Electronics and Information Guangxi University

In order to decrease the blocking probability of fast light-path set-up in the network,a novel strategy for optical flow switching is proposed,named dynamically initialized wavelength number protocol (DIWP),which can dynamically change the initialized wavelength number according to the traffic load of the network. Computer simulations are conducted to analyze the performance of the proposed strategy,which is based on forward reservation backward release (FRBR) mechanism. The results show that the initialized wavelength number can affect the blocking probability of the network.

关键词：路径设置开关协议光流光路计算机模拟初始化阻塞率

QSM-IDM -A novel quadrature spatial modulation based on interleaving division multiplexing for multiple antenna system

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Digital communications and Networks 2019年第3期5卷 183-188页

作者： Sherif K. El Dyasti Esam A.A. Hagras Hadia El-Hennawy Ain Shams Cairo Egypt Elec and Comm. Dept Technical Research Centre Cairo Egypt Faculty of Engineering Ain Shams Cairo Egypt

Quadrature Spatial Modulation (QSM) is a high spectral efficiency Multiple-Input Multiple Output (MIMO) technique used to improve the spectral efficiency of wireless communication systems. The main concept of QSM is to extend the spatial constellation of the conventional Spatial Modulation (SM) in both the in-phase and quadrature components of the data symbol. In this paper, because QSM-based on Interleaxdng Division Multiplexing (IDM) has not been introduced in the literature as a multiple antenna system, we introduced a novel scheme, called QSM system based on Interleaving Division Multiplexing (QSM-IDM). The antenna sets are also applied to a spreader, before being used to assign an antenna number for information transmission. Analysis and simulations for a flat fading channel show that the proposed QSM-IDM method significantly outperforms the original QSM system with the same data rate, while maintaining a relatively acceptable complexity. The obtained simulation results show that the conducted analysis yields significant improvements for the accuracy of the proposed scheme, with satisfactory complexity.

关键词： Interleaver Division Multiplexing (IDM) Multiple Input Multiple Output (MIMO) Spatial Modulation (SM) Quadrature Spatial Modulation (QSM)

Construction of time-frequency codes based on protograph LDPC codes in OFDM communication systems

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Journal of Systems Engineering and Electronics 2012年第3期23卷 335-341页

作者： Kaiyao Wang Yang Xiao Kiseon Kim Institute of Information Science Beijing Jiaotong UniversityBeijing 100044R R.China Department of Inform ation and comm unications Gwangju Institute of Science and TechnologyGwangju 500-712Korea

This paper proposes a scheme to construct time- frequency codes based on protograph low density parity check （LDPC） codes in orthogonal frequency division multiplexing （OFDM） communication systems. This approach synthesizes two techniques： protograph LDPC codes and OFDM. One symbol of encoded information by protograph LDPC codes corresponds to one sub-carrier, namely the length of encoded information equals to the number of sub-carriers. The design of good protograph LDPC codes with short lengths is given, and the proposed proto- graph LDPC codes can be of fast encoding, which can reduce the encoding complexity and simplify encoder hardware implementa- tion. The proposed approach provides a higher coding gain in the Rayleigh fading channel. The simulation results in the Rayleigh fading channel show that the bit error rate （BER） performance of the proposed time-frequency codes is as good as random LDPC- OFDM codes and is better than Tanner LDPC-OFDM codes under the condition of different fading coefficients.

关键词： time-frequency code protograph low density parity check (LDPC) code orthogonal frequency division multiplexing (OFDM) fast encoding algorithm.