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- 实验方案
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Pattern Reconfigurable Wideband Loop Antenna for Thorax Imaging
摘要： A unidirectional loop antenna that can achieve wideband pattern re-configurability from -40 to +40 degrees in azimuth plane is presented. The antenna is designed to fulfill the multi-slice (level) scanning requirements of electromagnetic imaging (EMI) systems for thorax imaging. To overcome the need for positioning of several antenna-arrays, and hence eliminate the mutual coupling related complications, a square-loop antenna with reconfigurable pattern is designed. To create a unidirectional radiation, the loop is loaded with capacitive gaps, which convert its radiation mechanism to that of two virtual dipole arrays with quadrature phase excitation. By utilizing this feature, the location of the gaps are varied on the loop's structure to form virtual dipole arrays in different directions, thus rotating the radiation pattern without physically moving the structure of the antenna. As a proof of concept, six gaps were created on the loop and each gap is loaded with a PIN diode to electronically switch between the positions of the designed gaps, thus enabling changing the radiation direction. The proposed antenna can achieve a compact size of 0.32λ×0.32λ×0.002λ (λ is the wavelength of the lowest resonance of the antenna) and a wide fractional bandwidth of 32% at 0.8-1.15 GHz, with a peak gain and front-to-back-ratio of 2.1 dBi and 8 dB, respectively. The antenna is successfully tested on a thorax imaging platform to detect small volume of water (5 mL) inside lungs as an emulation of early pulmonary edema.
关键词： unidirectional antenna,virtual dipole array,pattern reconfigurable antenna,loop antenna,Electromagnetic imaging,wideband antenna
更新于2025-09-23 15:23:52
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A Novel Miniaturized Planar Ultra-Wideband Antenna
摘要： A novel miniaturized planar ultra-wideband antenna is proposed. The antenna design comprises an electromagnetically coupled structure and a tapered radiating slot, while a triangular slot is etched on the ground plane. The antenna miniaturization is realized by adopting an electromagnetically coupled structure formed by the notched half-ellipse patch and the strip attached to the ground. The proposed antenna can yield a large 10-dB impedance bandwidth ranging from 1.5 to 10.4 GHz with satisfactory radiation properties. It also features a physical size of 37.4 mm × 64 mm, equivalent to a compact electrical size of 0.19λ × 0.32λ at 1.5 GHz. The important design parameters are analyzed to comprehend the operating principle of the antenna. A good agreement between the simulated and measured results is achieved.
关键词： compact antenna,Ultra-wideband antenna,planar antenna,antenna miniaturization
更新于2025-09-23 15:23:52
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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) - Hermite-Gaussian beams with orbital angular momentum
摘要： A conformal permeable toroidal antenna operating in both a vertically polarized monopole mode and circularly polarized (CP) dipole mode in the UHF frequency range is designed based on theory of magneto-dielectric radiators. This antenna has been fabricated using a new advanced ferromagnetic laminate composite material whose high impedance and anisotropic properties enable an antenna that radiates via magnetic currents. The antenna, less than 0.5 m in diameter and less than 2 cm thick, was fabricated and tested. Including the imperfections of the feed network and a simple matching scheme, the antenna operates from 200 to 500 MHz with an input match of better than 10 dB, CP dipole realized gain as high as 2 dBi, and monopole mode vertically polarized gain as high as 1 dBi.
关键词： ferromagnetic materials,wideband antenna,multimode antenna,multifunction antenna,Conformal antennas
更新于2025-09-23 15:21:01
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Input Filter Capacitance and Inductance Design for Photovoltaic Systems
摘要： A conformal permeable toroidal antenna operating in both a vertically polarized monopole mode and circularly polarized (CP) dipole mode in the UHF frequency range is designed based on theory of magneto-dielectric radiators. This antenna has been fabricated using a new advanced ferromagnetic laminate composite material whose high impedance and anisotropic properties enable an antenna that radiates via magnetic currents. The antenna, less than 0.5 m in diameter and less than 2 cm thick, was fabricated and tested. Including the imperfections of the feed network and a simple matching scheme, the antenna operates from 200 to 500 MHz with an input match of better than 10 dB, CP dipole realized gain as high as 2 dBi, and monopole mode vertically polarized gain as high as 1 dBi.
关键词： multifunction antenna,ferromagnetic materials,multimode antenna,wideband antenna,Conformal antennas
更新于2025-09-23 15:19:57
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3 Practical uses for topological photonics: An obscure phenomenon could improve chips, lasers, and quantum circuitry
摘要： A conformal permeable toroidal antenna operating in both a vertically polarized monopole mode and circularly polarized (CP) dipole mode in the UHF frequency range is designed based on theory of magneto-dielectric radiators. This antenna has been fabricated using a new advanced ferromagnetic laminate composite material whose high impedance and anisotropic properties enable an antenna that radiates via magnetic currents. The antenna, less than 0.5 m in diameter and less than 2 cm thick, was fabricated and tested. Including the imperfections of the feed network and a simple matching scheme, the antenna operates from 200 to 500 MHz with an input match of better than 10 dB, CP dipole realized gain as high as 2 dBi, and monopole mode vertically polarized gain as high as 1 dBi.
关键词： Conformal antennas,ferromagnetic materials,multimode antenna,multifunction antenna,wideband antenna
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Cost-Effective Snow Removal from Solar Panels
摘要： A conformal permeable toroidal antenna operating in both a vertically polarized monopole mode and circularly polarized (CP) dipole mode in the UHF frequency range is designed based on theory of magneto-dielectric radiators. This antenna has been fabricated using a new advanced ferromagnetic laminate composite material whose high impedance and anisotropic properties enable an antenna that radiates via magnetic currents. The antenna, less than 0.5 m in diameter and less than 2 cm thick, was fabricated and tested. Including the imperfections of the feed network and a simple matching scheme, the antenna operates from 200 to 500 MHz with an input match of better than 10 dB, CP dipole realized gain as high as 2 dBi, and monopole mode vertically polarized gain as high as 1 dBi.
关键词： ferromagnetic materials,wideband antenna,multimode antenna,multifunction antenna,Conformal antennas
更新于2025-09-16 10:30:52
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Wideband Rectangular Double-Ring Nanoribbon Graphene-Based Antenna for Terahertz Communications
摘要： A wideband nanoribbon graphene-based antenna with double rectangular rings for terahertz (THz) applications is presented. The wideband and efficient graphene-based antenna on physical parameters is developed in this paper. The antenna has a wide impedance bandwidth of 26% at the center frequency of 1 THz, minimum return loss equal to 24 dB and average radiation efficiency approximately equal to 44% is obtained. An average gain of 2.45 dB is achieved at the operational frequency band. The goal of this paper is to provide an antenna with capabilities of being wideband, efficient and re-configurable with a simple and single-layer structure for THz communication.
关键词： Double-ring antenna,wideband antenna,graphene,terahertz,THz,re-con?gurable,nanoribbon antenna
更新于2025-09-11 14:15:04
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A Wideband Substrate Integrated Waveguide Fed Open Slot Antenna
摘要： In this work, we introduce a new structure of an open slot antenna excited by a substrate-integrated-waveguide (SIW) feed to obtain a wide bandwidth of about 60%. Different from conventional slot antennas, two short sides of the slot are open which do not connect to any metal. To excite the open slot, a SIW section is used as the feed. In this way, the antenna is constructed on a single laminate which includes the feeding structure and the radiator. The open slot structure serves as a single-mode resonator with a low Q-factor, and thus contributes a much wider bandwidth than that of conventional slot antennas simultaneously maintains stable radiation performance. Intensive parametric studies were implemented to provide a design guideline. To verify our design, antenna prototypes were fabricated and measured. The measured results validate that the antenna achieves a wide impedance bandwidth of 59.3% from 50.8 GHz to 93.6 GHz. Meanwhile, the radiation patterns keep stable over the entire operating frequency band. This new type of slot antenna with wide bandwidth and planar structure is a good candidate for mmW applications.
关键词： wideband antenna,substrate integrated waveguide,millimeter-wave,Slot antenna
更新于2025-09-11 14:15:04
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[IEEE 2018 IEEE International Conference on Computational Electromagnetics (ICCEM) - Chengdu, China (2018.3.26-2018.3.28)] 2018 IEEE International Conference on Computational Electromagnetics (ICCEM) - Design of a Compact Wideband Dual-Polarization Antipodal Vivaldi Antenna Array
摘要： A compact wideband dual-polarization antipodal Vivaldi antenna is proposed in this paper. This proposed antenna mainly consists of two orthogonal antipodal Vivaldi antennas and one cross-shaped metal block. Each of the antipodal Vivaldi antennas with three layers of metal is etched on the two layers of substrates with a size of 38×42×1.5 mm3. Moreover, the cross-shaped metal block with a height of 44 mm is mounted on the corner of the reflection ground plane in each periodic cell, which can fix these antennas enabling of guaranteeing the robustness of this proposed antenna. Obviously, compared to the traditional Vivaldi antenna, this proposed antenna is convenient to replace some elements if necessary. In additional, the simulated imped- ance bandwidth (active VSWR≤3) for both horizontal polariza- tion antenna and vertical polarization antenna is about 94.5%, ranging 1.2 GHz to 3.35 GHz, while the main beam is scanning from -45o to 45o in azimuth plane and from -30o to 30o in eleva- tion plane. The detailed simulated results and analysis of the proposed conformal antenna array will be presented.
关键词： Wideband antenna,Dual-polarization,Antipodal Vivaldi antenna
更新于2025-09-10 09:29:36
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[Institution of Engineering and Technology 12th European Conference on Antennas and Propagation (EuCAP 2018) - London, UK (9-13 April 2018)] 12th European Conference on Antennas and Propagation (EuCAP 2018) - Wideband Millimeter-Wave End-Fire Magneto-Electric Dipole Antenna Fed by Substrate Integrated Coaxial Line
摘要： A wideband millimeter-wave magneto-electric (ME) dipole antenna with end-?re radiation, which is fed by the substrate integrated coaxial line (SICL), is designed, fabricated, and measured. First, the ME-dipole antenna excited by a planar L-probe is presented to realize wideband performance. Then, a wideband impedance conversion structure is used to connect the antenna and the feeding port. A simple conversion structure for the SICL to the grounded coplanar waveguide is used for the antenna test. Finally, the simulation and measurement results validate the proposed end-?re ME-dipole antenna. The overall bandwidth is greater than 40% considering both impedance bandwidth and 3-dB gain bandwidth.
关键词： wideband antenna,magneto-electric (ME) dipole antenna,substrate integrated coaxial line (SICL),end-?re
更新于2025-09-04 15:30:14