- 标题
- 摘要
- 关键词
- 实验方案
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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) - The Influence of Terahertzand Middle-Infrared Laser Radiationon the Membrane-Dependent Properties of Ratsa?? Red Blood Cells
摘要： A novel planar ultrathin electronically steerable parasitic array radiator (ESPAR) is presented in this paper. Through theoretical analysis of the electric fields of orthogonally crossed dipoles in phase quadrature, it is found that the crossed dipoles radiate linearly polarized wave with a rotational electric field in the azimuth plane. This characteristic is then utilized to design a planar crossed dipole ESPAR, termed as “CD-ESPAR.” Furthermore, a simple but effective impedance matching method is also proposed and analyzed. To verify these concepts, a prototype with compact size and very low profile (0.42 λ0 × 0.42 λ0 × 0.006 λ0) resonating at 2.3 GHz is designed, fabricated, and measured. The measured results indicate that the proposed antenna achieves more than 17.8% impedance bandwidth and can produce four directional beams, covering the whole azimuth plane. Owing to its planar ultrathin structure, compact size, electronically beam-switching ability, low power, and low cost characteristics, it is promising for applications in wireless communications.
关键词： Beam-switching,planar antenna,smart antenna,crossed dipoles,electronically steerable parasitic array radiator (ESAPR)
更新于2025-09-23 15:21:01
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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) - Coherence Properties of Multi-Section Semiconductor Frequency Swept Lasers
摘要： A novel planar ultrathin electronically steerable parasitic array radiator (ESPAR) is presented in this paper. Through theoretical analysis of the electric fields of orthogonally crossed dipoles in phase quadrature, it is found that the crossed dipoles radiate linearly polarized wave with a rotational electric field in the azimuth plane. This characteristic is then utilized to design a planar crossed dipole ESPAR, termed as “CD-ESPAR.” Furthermore, a simple but effective impedance matching method is also proposed and analyzed. To verify these concepts, a prototype with compact size and very low profile (0.42 λ0 × 0.42 λ0 × 0.006 λ0) resonating at 2.3 GHz is designed, fabricated, and measured. The measured results indicate that the proposed antenna achieves more than 17.8% impedance bandwidth and can produce four directional beams, covering the whole azimuth plane. Owing to its planar ultrathin structure, compact size, electronically beam-switching ability, low power, and low cost characteristics, it is promising for applications in wireless communications.
关键词： crossed dipoles,planar antenna,smart antenna,Beam-switching,electronically steerable parasitic array radiator (ESAPR)
更新于2025-09-19 17:13:59
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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) - Monolithic CZTS/Si tandem cells: development of multilayer structures for the intermediate contact
摘要： A novel planar ultrathin electronically steerable parasitic array radiator (ESPAR) is presented in this paper. Through theoretical analysis of the electric ?elds of orthogonally crossed dipoles in phase quadrature, it is found that the crossed dipoles radiate linearly polarized wave with a rotational electric ?eld in the azimuth plane. This characteristic is then utilized to design a planar crossed dipole ESPAR, termed as “CD-ESPAR.” Furthermore, a simple but effective impedance matching method is also proposed and analyzed. To verify these concepts, a prototype with compact size and very low pro?le (0.42 λ0 × 0.42 λ0 × 0.006 λ0) resonating at 2.3 GHz is designed, fabricated, and measured. The measured results indicate that the proposed antenna achieves more than 17.8% impedance bandwidth and can produce four directional beams, covering the whole azimuth plane. Owing to its planar ultrathin structure, compact size, electronically beam-switching ability, low power, and low cost characteristics, it is promising for applications in wireless communications.
关键词： crossed dipoles,planar antenna,smart antenna,Beam-switching,electronically steerable parasitic array radiator (ESAPR)
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE Research and Applications of Photonics in Defense Conference (RAPID) - Miramar Beach, FL, USA (2019.8.19-2019.8.21)] 2019 IEEE Research and Applications of Photonics in Defense Conference (RAPID) - Nonlinear Metasurfaces for Optical Applications
摘要： A novel planar ultrathin electronically steerable parasitic array radiator (ESPAR) is presented in this paper. Through theoretical analysis of the electric fields of orthogonally crossed dipoles in phase quadrature, it is found that the crossed dipoles radiate linearly polarized wave with a rotational electric field in the azimuth plane. This characteristic is then utilized to design a planar crossed dipole ESPAR, termed as “CD-ESPAR.” Furthermore, a simple but effective impedance matching method is also proposed and analyzed. To verify these concepts, a prototype with compact size and very low profile (0.42 λ0 × 0.42 λ0 × 0.006 λ0) resonating at 2.3 GHz is designed, fabricated, and measured. The measured results indicate that the proposed antenna achieves more than 17.8% impedance bandwidth and can produce four directional beams, covering the whole azimuth plane. Owing to its planar ultrathin structure, compact size, electronically beam-switching ability, low power, and low cost characteristics, it is promising for applications in wireless communications.
关键词： Beam-switching,planar antenna,smart antenna,crossed dipoles,electronically steerable parasitic array radiator (ESAPR)
更新于2025-09-19 17:13:59
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A 20-GHz-band 64×64 Hollow Waveguide Two-Dimensional Butler Matrix
摘要： In this paper, a 20-GHz-band 64×64 hollow waveguide Butler matrix is proposed. By using two-plane short slot couplers and a modified diagram, a short-axis two dimensional Butler matrix is realized. The design method of the diagram and components is presented. The Butler matrix is composed of two plane hybrids, cross couplers and phase shifters. The designed Butler matrix is fabricated by milling and screwing together nine aluminum plates. The dimensions and weight are 86.40 mm × 74.19 mm × 396.34 mm and 7.0 kg, respectively. Transmission characteristics as a beam switching circuit are characterized by measurements, with a low insertion loss of less than 1.8 dB and an excitation error of 4-dB and 40-deg. standard deviation. Radiation characteristics as a 64-beam antenna are measured, and a wide coverage area of 40% of the hemisphere and high directivity of more than 18.7 dBi were determined by measurements.
关键词： two-plane short slot coupler,Butler matrix,two dimensional beam switching,Hollow waveguide
更新于2025-09-16 10:30:52
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Plastic-Filled Dual-Polarized Lens Antenna for Beam Switching in the Ka-Band
摘要： This article presents a circular lens antenna for wide-angle beam-steering and for dual-polarized operation at mm-wave frequencies (27–30 GHz). The lens consists of a dielectric disc and two parallel plates, whose vertical spacing is varied linearly to achieve a suitable effective refraction index pro?le for the polarization parallel to the plates. The desired refraction pro?le is that of the Luneburg lens. The variation in plate spacing has negligible effect on the polarization perpendicular to the plates and, therefore, the dielectric material is selected such that the circular shape of the lens approximates the dimensions of lens. This way the lens provides the extended hemispherical focusing or collimation for both linear polarizations. The lens is fed with square waveguides supporting both polarizations. Several feeding waveguides allow beam-switching over a wide angular range. The designed lens antenna was fabricated, and the simulation and measurement results agree well and show that the proposed antenna concept is a valid solution for the upcoming 5G technologies, for instance as the access-point antenna. The antenna provides a ±50° beam-scanning range in both polarizations, and the realized gain is mostly between 9 and 12 dBi for the main beam. The measured re?ection coef?cient is mainly below ?10 dB for both polarizations across the whole frequency band.
关键词： 5G,base station,mm-wave,Lens antenna,waveguide,access point,beam-switching
更新于2025-09-12 10:27:22
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One-Body 2-D Beam-Switching Butler Matrix with Waveguide Short-Slot 2-Plane Couplers
摘要： A 42 × 42-way one-body 2-D beam-switching Butler matrix with waveguide short-slot 2-plane couplers is designed and fabricated in the 22 GHz band. The one-body con?guration using the commutativity and the overlapping of units allows reducing the size and loss in comparison with a cascade of matrices beam-switching for the horizontal and the vertical planes. It is achieved by replacing 2×2-way 1-plane couplers in the conventional block con?guration for a Butler matrix with 22 × 22-way 2-plane couplers. The measured bandwidth is approximately 2% restricted by the frequency characteristics of the 2-plane couplers. In the radiation from the aperture array antenna of the 42 output ports, the 3.9 dB-down coverage of 3-D solid angle by the sixteen beams is around 1.72 steradian which is same as 27.4% of hemisphere at the design frequency for the aperture spacing of 0.73 × 0.73 wavelength.
关键词： waveguide short-slot coupler,beam-switching,Butler matrix
更新于2025-09-11 14:15:04
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Electronically Beam-Steering Antenna with Active Frequency Selective Surface
摘要： A beam-sweeping antenna utilizing a novel active frequency selective surface (FSS) is developed in this letter. It is comprised of a simple dipole and a cylindrical FSS formed by six columns of unit cells. The dipole used as a radiating source is situated at the center of the cylindrical FSS. The radiation pattern of the antenna could be reconfigured by controlling the states of the PIN diodes in the FSS. The dimension of the whole antenna is 0.75 λg × 0.75 λg × 1.57 λg (λg is the guided wavelength at its resonant frequency). Experimental results demonstrate that the presented beam-steering antenna can operate at 2.45 GHz and the main beam can be swept across the whole azimuth plane with a peak gain of 8.15 dBi.
关键词： beam-sweeping,frequency selective surface,Radiation pattern,beam-switching
更新于2025-09-10 09:29:36
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Spatio-Temporal Impact of Hand and Body Blockage for Millimeter-Wave User Equipment Design at 28 GHz
摘要： The recently proposed channel model by the Third Generation Partnership Project for fifth generation New Radio (5G-NR) systems at millimeter-wave carrier frequencies in TR38.901 provides a good starting point for understanding the impact of propagation, material penetration, and blockage in cellular access systems. With this backdrop, the focus of this article is on hand and body blockage which have a significant bearing on user equipment (UE) design and in the practical viability of millimeter-wave systems. Building on TR38.901, we first study hand and body blockage loss with experiments using a 28 GHz experimental prototype that emulates a 5G base station and a form-factor UE. These measurement estimates show that while blockage losses can be substantial, they are significantly lower than the agreed model in TR38.901. We then study the implications of these revised estimates on spherical coverage with the UE. For this, we consider two form-factor UE designs: a face design and an edge design. Our studies show that while both designs are generally comparable in terms of spherical coverage, practical design considerations favor the edge design over the face design. We finally report on the timescales at which blockage events occur and show that given the symbol periods in 5G-NR, it is possible to implement mitigation strategies to overcome blockage (e.g., switch beams at the UE from a blocked path to an unblocked path).
关键词： body blockage,hand blockage,user equipment design,beam switching,spherical coverage,millimeter-wave,5G
更新于2025-09-09 09:28:46