- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Odessa, Ukraine (2018.9.4-2018.9.7)] 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Impedance Matching of Dipole Antennas by Metal Rod and Disk Placing
摘要： It has been researched experimentally and theoretically the impedance-matching possibility of dipole antenna with a coaxial feeder circuit. It has been made in case of a symmetrical dipole antenna placed parallel to a flat perfectly conducting screen by two bracket. It has been chosen a metal pins and discs of small electrical sizes as impedance-matching elements, which actually are placed between the dipole and the screen. Their dimensions and position relative to the dipole can be changed within certain small limits. The configuration and all dimensions of the tuned antenna has been entered into a computer for the calculation of the directivity patterns and dependence of the VSWR antenna on frequency. It is proved that such tuning elements allow to ensure good impedance-matching of the antenna and the feeder circuit, and also that practically does not affect on its directivity pattern.
关键词： near field region,dipole antenna,impedance matching,directivity pattern,flat screen
更新于2025-09-23 15:21:21
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[IEEE 2019 XVIII Workshop on Information Processing and Control (RPIC) - Bah?-a Blanca, Argentina (2019.9.18-2019.9.20)] 2019 XVIII Workshop on Information Processing and Control (RPIC) - Impact Produced by a Photovoltaic System on the Energy Utilization in an Educational Building
摘要： Enhancements of the directivity and front-to-back ratio (FTBR) of a metamaterial-inspired electrically small, linearly polarized, coaxially-fed Egyptian axe dipole antenna are considered. They are accomplished with a particular augmentation of the original near-field-resonant-parasitic (NFRP) antenna with an additional NFRP element, a small disc conductor modified with two meanderline-shaped slots. The entire system is evaluated numerically with two independent computational electromagnetics simulators. The optimized results demonstrate an electrically small antenna (i.e., ka < 1.0) with a reasonably low profile (i.e., height ～ λ/10) that improves the directivity from 1.77 to 6.32 dB, increases the FTBR from 0 to > 20 dB, and maintains large half-power beamwidths, while having a radiation efficiency over 80% with nearly complete matching to a 50 Ω source.
关键词： efficiency,Directivity,metamaterial-inspired antennas,front-to-back ratio,electrically small antennas,parasitic elements
更新于2025-09-23 15:19:57
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[IEEE 2019 22nd International Conference on Electrical Machines and Systems (ICEMS) - Harbin, China (2019.8.11-2019.8.14)] 2019 22nd International Conference on Electrical Machines and Systems (ICEMS) - Research on maximum power point contrast tracking of photovoltaic system based on improved particle swarm algorithm
摘要： Measurement procedures for determining the radiated disturbances from electronic equipment are described in several IEC/CISPR standards and are well probed for frequencies up to 1 GHz. Above that frequency, radiation pattern of EUTs evolve complex forms so that the direction and magnitude of the maximum directivity is not known by design. Hence, standardized sampling approaches might underestimate the “true” maximum of the radiated emission. In this paper, an extension of these measurement procedures is proposed. The method uses a stochastic approach for estimating the maximum directivity based on the electrical size of the EUT. This is combined with a total radiated power measurement for a reduced sampling procedure to predict the maximum free-space, far-zone electric field. For validation purposes, an extensive 3-D scan of the radiation pattern of a generic EUT is performed. Different subsampling approaches are then investigated while the new prediction method is applied. It can be shown that the accuracy of the measurement procedures can be increased due to the proposed method.
关键词： prediction,sampling approach,unintentional electromagnetic radiator,Emission measurement,maximum directivity
更新于2025-09-19 17:13:59
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Zinc Indiffused Diced Ridge PPLN Waveguides for Photorefractive Damage Resistance and Spectral Engineering
摘要： It is demonstrated numerically that a metamaterial-inspired, low profile (height approximately λ/80), electrically small (ka = 0.45) Huygens source antenna can be designed to radiate at 300 MHz in its broadside direction with a high radiation efficiency and a large front-to-back ratio. Two electrically small, near-field resonant parasitic (NFRP) antennas are first designed. Both are based on a coax-fed dipole antenna. An electric dipole response is obtained by combining it with a tunable Egyptian axe dipole (EAD) NFRP element. A magnetic dipole response is obtained by spatially loading the driven dipole with tunable, extruded capacitively loaded loop (CLL) NFRP elements. The driven dipole and the EAD and CLL NFRP elements are combined together and retuned to achieve a broadside radiating Huygens source antenna. Two different designs, one with two CLL elements and one with four, are obtained, and their performance characteristics are compared.
关键词： Huygens source,Directivity,metamaterial-inspired antennas,electrically small antennas
更新于2025-09-19 17:13:59
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A Non-Isolated Step-up DC-AC Converter With Reduced Leakage Current for Grid-Connected Photovoltaic Systems
摘要： Measurement procedures for determining the radiated disturbances from electronic equipment are described in several IEC/CISPR standards and are well probed for frequencies up to 1 GHz. Above that frequency, radiation pattern of EUTs evolve complex forms so that the direction and magnitude of the maximum directivity is not known by design. Hence, standardized sampling approaches might underestimate the “true” maximum of the radiated emission. In this paper, an extension of these measurement procedures is proposed. The method uses a stochastic approach for estimating the maximum directivity based on the electrical size of the EUT. This is combined with a total radiated power measurement for a reduced sampling procedure to predict the maximum free-space, far-zone electric field. For validation purposes, an extensive 3-D scan of the radiation pattern of a generic EUT is performed. Different subsampling approaches are then investigated while the new prediction method is applied. It can be shown that the accuracy of the measurement procedures can be increased due to the proposed method.
关键词： Emission measurement,sampling approach,prediction,unintentional electromagnetic radiator,maximum directivity
更新于2025-09-19 17:13:59
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[IEEE 2019 7th International Japan-Africa Conference on Electronics, Communications, and Computations, (JAC-ECC) - Alexandria, Egypt (2019.12.15-2019.12.16)] 2019 7th International Japan-Africa Conference on Electronics, Communications, and Computations, (JAC-ECC) - Broadside/Endfire Switched Beam Double Ridge-Gap Waveguide H-plane Horn Antenna
摘要： Measurement procedures for determining the radiated disturbances from electronic equipment are described in several IEC/CISPR standards and are well probed for frequencies up to 1 GHz. Above that frequency, radiation pattern of EUTs evolve complex forms so that the direction and magnitude of the maximum directivity is not known by design. Hence, standardized sampling approaches might underestimate the “true” maximum of the radiated emission. In this paper, an extension of these measurement procedures is proposed. The method uses a stochastic approach for estimating the maximum directivity based on the electrical size of the EUT. This is combined with a total radiated power measurement for a reduced sampling procedure to predict the maximum free-space, far-zone electric field. For validation purposes, an extensive 3-D scan of the radiation pattern of a generic EUT is performed. Different subsampling approaches are then investigated while the new prediction method is applied. It can be shown that the accuracy of the measurement procedures can be increased due to the proposed method.
关键词： Emission measurement,sampling approach,prediction,unintentional electromagnetic radiator,maximum directivity
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Sozopol, Bulgaria (2019.9.6-2019.9.8)] 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Radiation Patterns of Monopole Nano-Antenna Placed on Finite Size Metal Screen
摘要： Directive properties of monopole nano-antenna formed by carbon nanotube placed perpendicularly to metal rectangular screen are investigated. On the base of the method of the uniform geometric diffraction theory the asymptotic solution of the 3D vector problem of diffraction of the field of impedance monopole with radius r and length l placed on the ideally conducting rectangular screen is obtained. The fast-active algorithms and software for calculating 3-D patterns of this radiating system are developed. Analysis of the radiation patterns and directivity versus the screen sizes is carried out.
关键词： ellipticity,directivity,carbon nanotube antenna,square screen,radiation pattern,impedance monopole
更新于2025-09-19 17:13:59
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[IEEE 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC & 34th EU PVSEC) - Waikoloa Village, HI (2018.6.10-2018.6.15)] 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC & 34th EU PVSEC) - Simulating High-Frequency Generation Profiles for Large Solar PV Portfolios
摘要： It is demonstrated numerically that a metamaterial-inspired, low profile (height approximately λ/80), electrically small (ka = 0.45) Huygens source antenna can be designed to radiate at 300 MHz in its broadside direction with a high radiation efficiency and a large front-to-back ratio. Two electrically small, near-field resonant parasitic (NFRP) antennas are first designed. Both are based on a coax-fed dipole antenna. An electric dipole response is obtained by combining it with a tunable Egyptian axe dipole (EAD) NFRP element. A magnetic dipole response is obtained by spatially loading the driven dipole with tunable, extruded capacitively loaded loop (CLL) NFRP elements. The driven dipole and the EAD and CLL NFRP elements are combined together and retuned to achieve a broadside radiating Huygens source antenna. Two different designs, one with two CLL elements and one with four, are obtained, and their performance characteristics are compared.
关键词： Huygens source,metamaterial-inspired antennas,electrically small antennas,Directivity
更新于2025-09-19 17:13:59
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Metasurface-enabled interference mitigation in visible light communication architectures
摘要： Light can be used for wireless information transmission apart from illumination; that is the key idea behind visible-light communication (VLC), one of the disruptive technologies of our days. It combines remarkably high data rates due to ultrashort wavelengths with huge reliability and security due to small distances; nevertheless, it substantially suffers from interference of neighboring light sources in multiple-link configurations. In this manuscript, we investigate a pair of light emitting diodes interfering each other and propose a simple nanoslit metasurface that radically increases the directivity of the transmitting beams. As a result, enhancement of the signal-to-interference ratio by several orders of magnitude is reported. The considered generic setup retains its beneficial features in the presence of realistic design defects and, accordingly, may inspire standardization efforts towards the adoption of VLC in next-generation heterogeneous communication networks.
关键词： directivity,metasurface,visible-light communications,radiation pattern,indoor environment
更新于2025-09-19 17:13:59
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[IEEE 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Rome, Italy (2019.6.17-2019.6.20)] 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Multispectral Photodetectors Based on PbS Colloidal Quantum Dots
摘要： It is demonstrated numerically that a metamaterial-inspired, low profile (height approximately λ/80), electrically small (ka = 0.45) Huygens source antenna can be designed to radiate at 300 MHz in its broadside direction with a high radiation efficiency and a large front-to-back ratio. Two electrically small, near-field resonant parasitic (NFRP) antennas are first designed. Both are based on a coax-fed dipole antenna. An electric dipole response is obtained by combining it with a tunable Egyptian axe dipole (EAD) NFRP element. A magnetic dipole response is obtained by spatially loading the driven dipole with tunable, extruded capacitively loaded loop (CLL) NFRP elements. The driven dipole and the EAD and CLL NFRP elements are combined together and retuned to achieve a broadside radiating Huygens source antenna. Two different designs, one with two CLL elements and one with four, are obtained, and their performance characteristics are compared.
关键词： Huygens source,Directivity,metamaterial-inspired antennas,electrically small antennas
更新于2025-09-19 17:13:59