| 1. |
- Algaba-Brazalez, A., et al.
(författare)
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Compact Polarization Transformation in a Geodesic Luneburg Lens Antenna
- 2021
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Ingår i: 2021 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting, APS/URSI 2021 - Proceedings. - : Institute of Electrical and Electronics Engineers Inc.. ; , s. 1992-1993
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Konferensbidrag (refereegranskat)abstract
- This paper describes the design of a compact polarizer that rotates the linear polarization of a fully metallic geodesic Luneburg lens antenna for applications requiring polarization diversity. The polarization rotation is achieved by loading the radiating aperture of the antenna with two metallic screens. The integrated antenna operates in the Ka-band, from 25 to 31 GHz, showing around 20% bandwidth with S11 below -10 dB, and a scanning range of 100°.
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| 2. |
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| 3. |
- Chernikov, Viktor, 1998, et al.
(författare)
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A Teflon-Filled Open-Ended Circular Waveguide Focal-Plane-Array Used for Sway Compensation in W-band 50dB-Gain Backhaul Reflector Antennas
- 2023
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Ingår i: 2023 International Conference on Electromagnetics in Advanced Applications, ICEAA 2023. ; , s. 340-345
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Konferensbidrag (refereegranskat)abstract
- The paper introduces a novel focal plane array (FPA) design aimed at enhancing the reliability of millimeter-wave backhaul communication links by compensating for the impact of antenna mounting structures' sways. This FPA is analyzed for an offset parabolic reflector antenna with the 40-cm aperture diameter at W-band frequencies (92-96 GHz). The FPA-fed reflector antenna generates multiple closely-overlapping beams to compensate for the expected antenna tilt range, equivalent to seven beamwidths. This study addresses major challenges associated with FPA design implementation at these high frequencies, including (i) the need for a small (≤ 0.75 λ) inter-element spacing for the required beam overlap, and (ii) manufacturing complexities of an array element ensuring optimal reflector illumination and impedance matching in the presence of mutual coupling effects. An analytical approach to the FPA pattern shaping for optimal reflector illumination is proposed and successfully validated via numerical optimization and measurements. Furthermore, our analysis of the total reflector-FPA system shows promising results, i.e. 56 - 68% antenna aperture efficiency (49 - 50 dBi directivity) for all beams with compliance to the radiation emission constraints (ETSI class 3) within ±89°.
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| 4. |
- Manholm, L., et al.
(författare)
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A two-dimensional all metal Luneburg lens using glide-symmetric holey metasurface
- 2018
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Ingår i: IET Conference Publications. - : Institution of Engineering and Technology.
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Konferensbidrag (refereegranskat)abstract
- A two-dimensional Luneburg lens multiport antenna at 28GHz is presented, where an all metal metasurface structure is used to control the effective refractive index. The metasurface lens has glide-symmetric pin-loaded holes in the two plates of the parallel plate waveguide lens. This glide-symmetric configuration enhances the bandwidth of operation for the same equivalent refractive index. Excellent port matching and radiation performance are demonstrated through simulations of the complete antenna that is fed with 11 waveguides.
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| 5. |
- Papageorgiou, I., et al.
(författare)
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An E-band cylindrical reflector antenna for wireless communication systems
- 2013
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Ingår i: 7th European Conference on Antennas and Propagation, EuCAP 2013. ; 2013, s. 524-528
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Konferensbidrag (refereegranskat)abstract
- The increasing demand of radio links with high data rates is satisfied by the allocation of new frequency spectrum. A novel cylindrical reflector antenna is designed to operate in the E-band (71-86 GHz), which was already allocated in 2003 for radio link applications. Presented simulation results are preliminary and the directivity of the antenna at the center frequency is calculated to be 41.4 dBi with an aperture efficiency of 60% or -2.2dB.
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| 6. |
- Quevedo-Teruel, Oscar, et al.
(författare)
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Glide-Symmetric Fully Metallic Luneburg Lens for 5G Communications at Ka-Band
- 2018
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Ingår i: IEEE Antennas and Wireless Propagation Letters. - : Institute of Electrical and Electronics Engineers Inc.. - 1536-1225 .- 1548-5757. ; 17:9, s. 1588-1592
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Tidskriftsartikel (refereegranskat)abstract
- Here, we propose a fully metallic implementation of a Luneburg lens operating at Ka-band with potential use for 5G communications. The lens is implemented with a parallel plate that is loaded with glide-symmetric holes. These holes are employed to produce the required equivalent refractive index profile of a Lune-burg lens. Glide symmetry and inner metallic pins are employed to increase the equivalent refractive index. The lens is fed with rectangular waveguides designed to match the height of the parallel plate, and it is ended with a flare to minimize the reflections.
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| 7. |
- Wang, Enlin, 1998, et al.
(författare)
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A 50 dBi E-Band Dual-reflector Antenna for 5G Backhauling with Auto-beam-tracking Function
- 2024
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Ingår i: IEEE Transactions on Antennas and Propagation. - 0018-926X .- 1558-2221. ; 72:6, s. 4874-4887
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Tidskriftsartikel (refereegranskat)abstract
- An ultra-high-gain E-band dual-reflector antenna for 5G backhaul with beam tracking function is proposed in this paper. Beam tracking is achieved by defocussing the feed away from the focus point of the sub-reflector, while keeping the interface with the transmit-receive unit stationary by applying a movable gap-waveguide configuration. The antenna has been prototyped and measured. The measured reflection coefficients remain below –10 dB for both horizontal and vertical polarizations over 71 – 86 GHz, almost independent from the offset positions of the feed. The measured radiation patterns agree well with the simulated ones, with a peak gain of about 50 dBi in the band and less than 1 dB gain drop for beam steering within ±2°. Finally, a low-cost and environmentally friendly mechanical tracking system is proposed, prototyped, and tested. Measurements have verified that the tracking system functions well for slow sways.
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| 8. |
- Yang, Jian, 1960, et al.
(författare)
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High-performance UWB mmWave smart bowtie array antenna technology for 5G access and backhauling systems
- 2021
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Ingår i: 2020 International Symposium on Antennas and Propagation, ISAP 2020. ; , s. 243-244
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Konferensbidrag (refereegranskat)abstract
- Smart Bowtie array antenna technology is a recently developed one, aiming to provide UWB solutions to antennas in 5G mmWave access and backhauling systems. This technology enables the simultaneous multiple beams with large beam scan angles and tracking ability, with high gain and high antenna efficiency over an ultra-wideband (UWB) at low manufacturing cost. This paper will presents several designs to show the features and characteristics of the technology.
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| 9. |
- Yaqoob Chaudhry, Sohaib, 1993, et al.
(författare)
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A Compact W-band Diplexer for Integration with an Electronically Steerable Focal Plane Array Antenna System
- 2023
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Ingår i: Asia-Pacific Microwave Conference Proceedings, APMC. ; , s. 315-317
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Konferensbidrag (refereegranskat)abstract
- A waveguide folded diplexer is presented that is designed to provide frequency division duplex operation of electronically steerable focal-plane-array (FPA) antennas for W-band wireless backhaul links. This design overcomes manufacturing challenges associated with small dimensions at these high frequencies (reaching the required tolerance of ± 15 μ m) and the difficulties of integration with the closely-spaced FPA elements. Bandpass filters for the 94-97 GHz and 106-109GHz bands are synthesized utilizing waveguide cavity TE102 resonators with inductive iris coupling through a combined analytical-numerical optimization approach. The final assembly has a three-fold compact 10th-order configuration and the prototype is manufactured using CNC milling. The measured reflection coefficients are ≤ -15dB, the isolation level is ≥ 55dB, and the insertion loss is 1dB.
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| 10. |
- Zetterström, Oskar, et al.
(författare)
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V-Band Geodesic Generalized Luneburg Lens Antenna with High Beam Crossover Gain
- 2023
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Ingår i: IEEE Transactions on Antennas and Propagation. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-926X .- 1558-2221. ; 71:9, s. 7591-7596
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Tidskriftsartikel (refereegranskat)abstract
- Quasi-optical beamformers provide attractive properties for antenna applications at millimeter-wave (mm-wave) frequencies. Antennas implemented with these beamformers have demonstrated wide-angle switching of directive beams, making them suitable as base station antennas for future communication networks. For these applications, it is essential to ensure a high beam crossover gain to provide a robust service to end users within the steering range. Here, we propose a geodesic generalized Luneburg lens antenna operating from 57 to 67 GHz that provides increased crossover gain compared to previously reported geodesic Luneburg lens antennas. The focal curve of the generalized Luneburg lens can be displaced from the beamformer, allowing for a higher angular resolution in the placement of the feed array along the focal curve. The lens is fed with 21 ridge waveguides with an angular separation of 5.1°, thus providing beam steering in a 102° range. The peak realized gain varies from 19 to 21 dBi throughout the steering and frequency ranges and the beam crossover gain is roughly 3 dB below the peak gain. The simulations are experimentally validated.
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