| 1. |
- Bärring, Maja, 1988, et al.
(författare)
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Factory Radio Design of a 5G Network in Offline Mode
- 2021
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Ingår i: IEEE Access. - 2169-3536 .- 2169-3536. ; 9, s. 23095-23109
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Tidskriftsartikel (refereegranskat)abstract
- The manufacturing industry is connecting people and equipment with new digital technologies, enabling a more continuous stream of data to represent processes. With more things connected, the interest in a connectivity solution that can support communication with high reliability and availability will increase. The fifth generation of telecommunication, i.e., 5G has promising features to deliver this, but the factory environment introduces new challenges to ensure reliable radio coverage. This will require efficient ways to plan the Factory Radio Design prior to installation. 3D laser scanning is used at an ever-increasing rate for capturing the spatial geometry in a virtual representation to perform layout planning of factories. This paper presents how to combine 3D laser scanning and physical optics (PO) for planning the Factory Radio Design of a cellular Long-Term Evolution (LTE) network (5G) in a virtual environment. 3D laser scanning is applied to obtain the spatial data of the factory and the virtual representation serves as the environment where PO computation techniques can be performed. The simulation result is validated in this paper by comparison to measurements of the installed network and empirical propagation models. The results of the study show promising opportunities to simulate the radio coverage in a virtual representation of a factory environment.
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| 2. |
- Iupikov, Oleg, 1983, et al.
(författare)
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A Cavity-Backed Patch Antenna with Distributed Multi-Port Feeding, Enabling Efficient Integration with Doherty Power Amplifier and Band-Pass Filter
- 2021
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Ingår i: IEEE Transactions on Antennas and Propagation. - 0018-926X .- 1558-2221. ; 69:8, s. 4412-4422
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Tidskriftsartikel (refereegranskat)abstract
- A joint design approach for co-integrated antenna and power amplifier (PA), employing a high-efficiency Doherty PA (DPA) architecture and including a band-pass RF filter, is proposed. This design is realized through the optimally distributed and balanced multi-port feeding of the cavity-backed patch antenna element that provides the desired (unique) loading conditions for the main and auxiliary PA branches and tailored power combining. A novelty and advantage of this feeding solution is that each pair of feeding points form a virtual common feeding centre of the radiating element; as a result, the radiation pattern remains power invariant when the port excitations change. A joint optimization of the integrated antenna-DPA transmitter is carried out to enhance the overall performance and maximize the bandwidth. This optimization is demonstrated through an example design for the sub-6 GHz telecommunication applications that target high power-efficiency (>50%) at the 6dB backed-off power levels and require RF-filtering in a compact integrated design. The latter challenge leads to a non-conventional implementation, which generally does not require the filter to be inserted between the antenna and the final output stage of the PA, and can be embedded in the topology with complex-valued source/load impedance values. Results of numerical studies are supported by measurements obtained with the antenna-DPA-filter prototype system.
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| 3. |
- Zhu, Yuqing, 1998, et al.
(författare)
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A Varactor-Based Reconfigurable Intelligent Surface Concept for 5G/6G mm-Wave Applications
- 2024
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Ingår i: 18th European Conference on Antennas and Propagation, EuCAP 2024.
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Konferensbidrag (refereegranskat)abstract
- A varactor-based reconfigurable intelligent surface (RIS) concept is presented for low-cost, high-precision beamforming of 5G/6G mm-waves. To enable this, we maximize the RIS unit cell (UC) phase coverage by (i) employing a varactor diode-tuned slotted-patch UC, and (ii) adding a metallic loop and via fence across the UC boundary, which also improves the bandwidth and angular insensitivity. In an infinite RIS environment, the UC exhibits a phase coverage of 330.7 degrees while maintaining the insensitivity of reflection coefficients up to 50-degree elevation angle. This UC design demonstrates a phase coverage that exceeds 315 degrees with under 0.7-dB reflection loss across a 11.6% bandwidth, where the capacitance tuning ratio of the considered commercial off-the-shelf varactor diode is only 1.8. A 15 × 15 RIS model with a 3-bit phase quantization is used for beam steering performance validation; it predicts the realized gain of 19.5 dBi for the 30-degree beam-steering direction at 28 GHz.
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| 4. |
- Bressner, Thomas A.H., et al.
(författare)
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Cell Partitioning Antenna System Performance in Multi-User Scenarios for mmWave Communications
- 2021
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Ingår i: IEEE Access. - 2169-3536 .- 2169-3536. ; 9, s. 127141-127149
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Tidskriftsartikel (refereegranskat)abstract
- Fixed-beam, high-gain antenna systems can be used for a finer partitioning of the currently used cell-sectoring. This partitioning has the benefit of reducing the number of users seen per antenna beam, which reduces interference. Furthermore, the high antenna gain allows for a high effective isotropic radiated power while keeping the transmit power low. In this paper, we study the performance of such a fixed-beam, high gain antenna system design for millimeter-wave mobile communications. The antenna system is designed to keep the inter-sector interference in a multi-site scenario low. The performance is analyzed for single- and multi-user environments. In single-input single-output mode, the 50th percentile of the signal-to-interference-plus-noise ratio lies between 12.5 dB to 39.7 dB if 3 to 0 interferers are present, respectively. For multiple-input multiple-output transmission using zero-forcing, the signal-to-interference-plus-noise ratio increases and the 50th percentile ranges from 36.1 dB to 43.3 dB if 3 to 0 interferes are present, respectively. By using maximum ratio transmission, the best performance is achieved with no interferers present, while a plunge in performance is observed with interferers. Furthermore, the study revealed that the narrow beam antenna system can also provide a clear signal separation for small spatial separations. In the given example, the signal-to-interference-plus-noise ratio is larger than 32.1 dB with 11 active antenna elements, where 2.8 meters separate the users. Hence, the paper shows that the cell-partitioning antenna systems provide coverage in the desired area while keeping the inter-sector interference low, and the considered transmission techniques can be used for situation optimized mobile communication links.
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| 5. |
- Cappellin, C., et al.
(författare)
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Design of a Push-Broom Multi-Beam Radiometer for Future Ocean Observations
- 2015
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Ingår i: 9th European Conference on Antennas and Propagation, EuCAP 2015, Lisbon, Portugal, 13-17 May 2015. - 9788890701856
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Konferensbidrag (refereegranskat)abstract
- The design of a push-broom multi-beam radiometer for future ocean observations is described. The radiometer provides a sensitivity one order of magnitude higher than a traditional conical scanning radiometer, and has the big advantage of being fully stationary relative to the satellite platform. Thanks to a dense focal plane array and a dedicated optimization procedure, the instrument can accurately measure in C, X and Ku band and as close as 15 km to the coast line.
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| 6. |
- Cappellin, C., et al.
(författare)
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Feed array breadboard for future passive microwave radiometer antennas
- 2018
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Ingår i: IET Conference Publications. ; 2018:CP741
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Konferensbidrag (refereegranskat)abstract
- The pattern of a 265 mm x 200 mm breadboard made of 35 x-polarized and 32 y-polarized Vivaldi antennas located above a finite ground plane is computed and measured at 6.9 GHz. The breadboard constitutes the feed array illuminating a 5 m conical scan antenna working at 6.9 GHz for next generation microwave radiometers for ocean observation. The analysis is done including mutual coupling between the elements, and in two commercial software, the MoM add-on to GRASP and CST. The breadboard is measured at the Spherical Near-Field Antenna Test Facility at the Technical University of Denmark.
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| 7. |
- Cappellin, Cecilia, et al.
(författare)
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Focal Plane Array Breadboard For Advanced Multiple Beam Radiometer Antennas
- 2017
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Ingår i: 38th ESA Antenna Workshop on Innovative Antenna Systems and Technologies for Future Space Missions. ; , s. 1-8
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The detailed design and RF analysis of a breadboard made by 35 x-polarized and 32 y-polarized Vivaldi antennas, placed 0.67 wavelength from each other and located above a finite ground plane, are described. The breadboard constitutes a representative part of the feed array illuminating a conical scan or push-broom antenna for next generation microwave radiometers for ocean observation. The analysis are done at 6.9 GHz including mutual coupling between the elements, and in two commercial software, i.e. CST and the MoM add-on to GRASP.
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| 8. |
- Cappellin, C., et al.
(författare)
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Novel multi-beam radiometers for accurate ocean surveillance
- 2014
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Ingår i: 8th European Conference on Antennas and Propagation, EuCAP 2014. - 9788890701849 ; , s. 3531-3535
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Konferensbidrag (refereegranskat)abstract
- Novel antenna architectures for real aperture multi-beam radiometers providing high resolution and high sensitivity for accurate sea surface temperature (SST) and ocean vector wind (OVW) measurements are investigated. On the basis of the radiometer requirements set for future SST/OVW missions, conical scanners and push-broom antennas are compared. The comparison will cover reflector optics and focal plane array configuration.
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| 9. |
- de lasson, Jakob R., et al.
(författare)
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Innovative Multi-Feed-Per-Beam Reflector Antenna for Space-Borne Conical-Scan Radiometers
- 2018
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Ingår i: 2018 IEEE ANTENNAS AND PROPAGATION SOCIETY INTERNATIONAL SYMPOSIUM ON ANTENNAS AND PROPAGATION & USNC/URSI NATIONAL RADIO SCIENCE MEETING. - 1522-3965. - 9781538671023 - 9781538671023 ; , s. 1729-1730
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Konferensbidrag (refereegranskat)abstract
- We present an antenna for use on conical-scan space-borne radiometers in C band and demonstrate that stringent radiometric requirements can be met. The antenna consists of a 5 m offset reflector fed by a focal plane array in a multi-feed-per-beam configuration, so far never used in ocean observation missions. We use distinct element beams and two optimization routines for obtaining element excitation amplitudes and phases, and with either routine, and in both x- and y-polarization, compliant beams, with footprint < 20 km, distance to coast < 20 km and accuracy < 0:25 K, are obtained. These results may pave the way for use of focal plane arrays with digital beamforming in future radiometric ocean observation missions.
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| 10. |
- Elsakka, Amr, 1984, et al.
(författare)
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A Design Concept of Power Efficient, High Gain Antenna System for mm-Waves Base Stations
- 2021
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Ingår i: 2021 15TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP). - 2164-3342.
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Konferensbidrag (refereegranskat)abstract
- A design concept for a phased-array-fed reflector antenna system intended for millimeter-wave base stations is presented. This concept is motivated by the need for efficient beamforming antenna systems with reduced power consumption as compared to the presently considered fully-populated large-scale MIMO arrays. The main idea is to use a high-gain reflector antenna to maximize the effective isotropic radiated power. That in turn, allows minimizing the number of active antenna elements of the phased-array feed, and hence limit the total supplied power. The proposed reflector antenna system is based on a torus reflector which is illuminated by an offset phased-array feed. We show how to determine the antenna design parameters to achieve the desired cell coverage.
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