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A Conformal Conical Archimedean Spiral Antenna for UWB Communications

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Chinese Journal of electronics 2015年第2期24卷 402-407页

作者： SONG Lizhong FANG Qingyuan School of electronics and information Engineering Harbin Institute of Technology at Weihai School of electronics and information Engineering Harbin Institute of Technology

In this paper, a wide-band miniaturized Conformal conical Archimedean spiral(CCARS) antenna is proposed for Ultra wideband(UWB) *** CCARS antenna utilizes the vertical space instead of horizontal space significantly saving the antenna installation space. We investigate the transformation from Planar Archimedean spiral(PARS) antenna to the CCARS antenna and the antenna miniaturization technique. Due to the using of flexible dielectric substrate, the PARS antenna can be bent freely, which assures the transformation from the PARS antenna to the CCARS antenna. To realize antenna miniaturization, zigzag shape arms are applied to the PARS antenna. Moreover, the CCARS antenna has good unidirectional radiation property that avoids the using of traditional absorber-loaded back cavity. The measured results of antenna prototype indicate that the Voltage standing wave ratio(VSWR) is below 2 over the frequency range from 1.3GHz to 9GHz. The antenna gain is higher than3.4d Bi and the Front to back(F/B) ratio is better than20 d B from 2GHz to 7GHz. In addition, good radiation patterns and broad 3d B beam width are also available for the CCARS antenna.

关键词： Ultra wideband(UWB) communications Conformal antenna Miniaturized antenna Archimedean spiral antenna Microstrip tapered Balun

Ultra-wideband direct-sequence design approach for multiple narrowb and interference suppression

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Journal of Systems Engineering and electronics 2013年第3期24卷 365-371页

作者： Huibin Xu Junjun Guo Xingjun Shi School of electronics and information Tongji University Tianhua college Shanghai Normal University Shaanxi Posts and Telecommunications college School of Economy and Trade Zhejiang Industry and Trade Vocational College

A novel direct sequence （DS） design method for suppressing the narrowband interference in DS spread spectrum ultra-wideband receivers is proposed. The method has low computational complexity and can be easily implemented in practical systems. Simulation results prove that the proposed method is effective to suppress the narrowband interference. Therefore, the integrity of both the ultra-wide bandwidth and the narrowband systems can be highly enhanced.

关键词： bit error rate (BER) narrowband interference Rayleigh-Ritz direct sequence (DS).

Adaptive network fuzzy inference system based navigation controller for mobile robotAdaptive network fuzzy inference system based navigation controller for mobile robot

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Frontiers of information Technology & Electronic Engineering 2019年第2期20卷 141-151页

作者： Panati SUBBASH Kil To CHONG Department of electronics and information Engineering Chonbuk National University Advanced electronics and information Research Center Chonbuk National University

Autonomous navigation of a mobile robot in an unknown environment with highly cluttered obstacles is a fundamental issue in mobile robotics research. We propose an adaptive network fuzzy inference system(ANFIS) based navigation controller for a differential drive mobile robot in an unknown environment with cluttered obstacles. Ultrasonic sensors are used to capture the environmental information around the mobile robot. A training data set required to train the ANFIS controller has been obtained by designing a fuzzy logic based navigation controller. Additive white Gaussian noise has been added to the sensor readings and fed to the trained ANFIS controller during mobile robot navigation, to account for the effect of environmental noise on sensor readings. The robustness of the proposed navigation controller has been evaluated by navigating the mobile robot in three different environments. The performance of the proposed controller has been verified by comparing the travelled path length/efficiency and bending energy obtained by the proposed method with reference mobile robot navigation controllers, such as neural network, fuzzy logic, and ANFIS. Simulation results presented in this paper show that the proposed controller has better performance compared with reference controllers and can successfully navigate in different environments without any collision with obstacles.

关键词： Adaptive network fuzzy inference system Additive white Gaussian noise Autonomous navigation Mobile robot

Dispersion characteristics of a slow wave structure with a modified photonic band gap

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Chinese Physics B 2011年第3期20卷 129-134页

作者：高喜杨梓强曹卫平姜彦南 School of Physical electronics University of Electronic Science and Technology of China information and Communication college Guilin University of Electronic Technology

This paper studies the dispersion characteristics of a modified photonic band-gap slow-wave structure with an open boundary by simulation and experiment. A mode launcher with a wheel radiator and a coupling probe is presented to excite a pure TM01-like mode. The cold test and simulation results show that the TM01-like mode is effectively excited and no parasitic modes appear. The dispersion characteristics obtained from the cold test are in good agreement with the calculated results.

关键词： modified photonic band-gap slow-wave structure TM01-like mode cold test

Through-Wall Tracking of Human Movers Using Continuous-Wave Radar

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Chinese Journal of electronics 2014年第2期23卷 334-340页

作者： DING Yipeng TANG Jingtian Cheng Dong Fang Guangyou School of Geosciences and information Physics Central South University School of Physics and electronics Central South University college of electrical and information engineering Hunan University Institute of electronics Chinese Academy of Sciences

An intelligent frequency fitting algorithm is presented for continuous-wave radar to track human movers through walls. With the proper fitting dimension,which is usually determined by the practical detection requirements, this technique can improve the localization accuracy and the tracking performance without introducing too much calculation burden, and more precisely identify different targets even in the frequency ambiguous *** technology can also help to match the estimation results to their corresponding targets automatically, which is of great importance to certain urban sensing applications,such as specific target surveillance and tracking. To further improve the detection performance and better identify the weak targets in the presence of strong noise, CLEAN algorithm and adaptive filter technology are also *** results are provided to illustrate the algorithm performance.

关键词： Continuous-wave through-wall radar(CW-TWR) Frequency ambiguous effect Frequency fitting technology CLEAN algorithm Adaptive filt

Characteristics of a Normal Glow Discharge Excited by DC Voltage in Atmospheric Pressure Air

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Plasma Science and Technology 2013年第11期15卷 1149-1153页

作者：李雪辰赵欢欢贾鹏英 college of Physics Science and Technology Hebei University Key Laboratory of Photo-electronics information Materials of Hebei Province

Atmospheric pressure glow discharges were generated in an air gap between a needle cathode and a water anode. Through changing the ballast resistor and gas gap width between the electrodes, it has been found that the discharges are in normal glow regime judged from the currentvoltage characteristics and visualization of the discharges. Results indicate that the diameter of the positive column increases with increasing discharge current or increasing gap width. Optical emission spectroscopy is used to calculate the electron temperature and vibrational temperature. Both the electron temperature and the vibrational temperature increases with increasing discharge current or increasing gap width. Spatially resolved measurements show that the maxima of electron temperature and vibrational temperature appeared in the vicinity of the needle cathode.

关键词： atmospheric pressure glow discharge positive column optical emission spectroscopy electron temperature vibrational temperature

Hybrid diffusion approximation in highly absorbing media and its effects of source approximation

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Chinese Optics Letters 2009年第6期7卷 515-518页

作者：田会娟刘迎王利军张宇辉肖立峰 college of Science Key Laboratory of Opto-Electronics Information Technical ScienceMinistry of Education of ChinaTianjin University

A modified diffusion approximation model called the hybrid diffusion approximation that can be used for highly absorbing media is investigated. The analytic solution of the hybrid diffusion approximation for reflectance in two-source approximation and steady-state case with extrapolated boundary is obtained. The effects of source approximation on the analytic solution are investigated, and it is validated that two-source approximation in highly absorbing media to describe the optical properties of biological tissue is necessary. Monte Carlo simulation of recovering optical parameters from refiectant data is done with the use of this model. The errors of recovering μ＇s and μ＇s are smaller than 15% for the reduced albedo between 0.77 and 0.5 with the source-detector separation of 0.4-3 mm.

关键词： Electromagnetic wave absorption Monte Carlo methods Optical properties

Comparing Set Reconciliation Methods Based on Bloom Filters and Their Variants

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Tsinghua Science and Technology 2016年第2期21卷 157-167页

作者： Zhiyao Hu Xiaoqiang Teng Deke Guo Bangbang Ren Pin Lv Zhong Liu college of information System and Management National University of Defense TechnologyChangsha 410073China School of Computer Electronics and InformationGuangxi UniversityNanning 530004China.

Set reconciliation between two nodes is widely used in network applications. The basic idea is that each member of a node pair has an object set and seeks to deliver its unique objects to the other member. The Standard Bloom Filter （SBF） and its variants, such as the Invertible Bloom Filter （IBF）, are effective approaches to solving the set reconciliation problem. The SBF-based method requires each node to represent its objects using an SBF, which is exchanged with the other node. A receiving node queries the received SBF against its local objects to identify the unique objects. Finally, each node exchanges its unique objects with the other node in the node pair. For the IBF- based method, each node represents its objects using an IBF, which is then exchanged. A receiving node subtracts the received IBF from its local IBF so as to decode the different objects between the two sets. Intuitively, it would seem that the IBF-based method, with only one round of communication, entails less communication overhead than the SBF-based method, which incurs two rounds of communication. Our research results, however, indicate that neither of these two methods has an absolute advantages over the others. In this paper, we aim to provide an in-depth understanding of the two methods, by evaluating and comparing their communication overhead. We find that the best method depends on parameter settings. We demonstrate that the SBF-based method outperforms the IBF-based method in most cases. But when the number of different objects in the two sets is below a certain threshold, the IBF-based method outperforms the SBF-based method.

关键词： set reconciliation bloom filter communication overheads

Effects of Gas Flow Rate on the Discharge Characteristics of a DC Excited Plasma Jet

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Plasma Science and Technology 2015年第9期17卷 738-742页

作者：李雪辰贾鹏英狄聪鲍文婷张春燕 college of Physics Science & Technology Hebei University Key Lab of Photo-electronics information Materials of Hebei Province

A direct current（DC） source excited plasma jet consisting of a hollow needle anode and a plate cathode has been developed to form a diffuse discharge plume in ambient air with flowing argon as the working *** optical and electrical methods,the discharge characteristics are investigated for the diffuse plasma *** indicate that the discharge has a pulse characteristic,under the excitation of a DC *** discharge pulse corresponds to the propagation process of a plasma bullet travelling from the anode to the *** is found that,with an increment of the gas flow rate,both the discharge plume length and the current peak value of the pulsed discharge decrease in the laminar flow mode,reach their minima at about1.5 L/min,and then slightly increase in the turbulent ***,the frequency of the pulsed discharge increases in the laminar mode with increasing the argon flow rate until the argon flow rate equals to about 1.5 L/min,and then slightly decreases in the turbulent mode.

关键词： DC excited plasma jet plasma bullet pulsed discharge gas flow rate laminar mode turbulent mode