| 1. |
- Carlsson, Jan, 1962, et al.
(författare)
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Reverberation chamber for OTA measurements: The history of a dream!
- 2017
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Ingår i: 2017 11th European Conference on Antennas and Propagation, EUCAP 2017. - 9788890701870 ; , s. 237-241
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Konferensbidrag (refereegranskat)abstract
- In the late 1990's Professor Per-Simon Kildal got the idea that reverberation chambers could be used for characterizing small antennas and mobile devices. Many thought the idea was crazy but he was persistent and worked hard to realize his dream to build a small chamber that could be used by the wireless industry. This paper gives a short history of the research at Chalmers and the creation of the company Bluetest that both were instrumental for realizing the dream.
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| 2. |
- Ebrahimpouri, Mahsa, et al.
(författare)
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Design of microwave components in groove gap waveguide technology implemented by holey EBG
- 2017
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Ingår i: 2017 11th European Conference on Antennas and Propagation, EUCAP 2017. - : Institute of Electrical and Electronics Engineers (IEEE). - 9788890701870 ; , s. 746-748
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Konferensbidrag (refereegranskat)abstract
- In this paper, the feasibility of the implementation of microwave components in groove gap waveguide technology by glide-symmetry holey EBG is discussed. Using this technology, microwave components and antennas which were previously designed for hollow metallic waveguides can be manufactured in a cost-effective way at high frequencies. To show the viability of the proposed solution a phase shifter and a mode converter are designed as examples of typical components for antenna systems.
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| 3. |
- Ebrahimpouri, Mahsa, et al.
(författare)
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Wideband glide-symmetric holey structures for gap-waveguide technology
- 2017
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Ingår i: 2017 11th European Conference on Antennas and Propagation, EUCAP 2017. - : Institute of Electrical and Electronics Engineers (IEEE). - 9788890701870 ; , s. 1658-1660
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Konferensbidrag (refereegranskat)abstract
- In this paper, the stop-band of two different holey glide-symmetric EBG lattices is studied. The results show that glide-symmetric EBG structures have potential to achieve wide stop-bands by polygonal lattices. Potential application of the proposed EBG structure in gap-waveguide technology is discussed in the second part of the paper.
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| 4. |
- Ghasemifard, Fatemeh, et al.
(författare)
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Mode matching analysis of two dimensional glide-symmetric corrugated metasurfaces
- 2017
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Ingår i: 2017 11th European Conference on Antennas and Propagation, EUCAP 2017. - : Institute of Electrical and Electronics Engineers (IEEE). - 9788890701870 ; , s. 749-751
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Konferensbidrag (refereegranskat)abstract
- The mode matching method for analysing two dimensional doubled corrugated metasurfaces, including glide-symmetric corrugated metasurfaces, embedded in a thin parallel plate waveguide is presented. This method is accurate, fast, and without any limitations on the parameters.
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| 5. |
- Iupikov, Oleg, 1983, et al.
(författare)
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Prediction of Far-Field Pattern Characteristics of Phased Array Fed Reflector Antennas by Modeling Only a Small Part of the Array - Case Study of Spaceborne Radiometer Antennas
- 2017
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Ingår i: Proceedings of the 11th European Conference on Antennas and Propagation, EUCAP 2017, Paris, France, April 2017. - 2164-3342. - 9788890701870 ; , s. 2636-2639.
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Konferensbidrag (refereegranskat)abstract
- In this work we present an approach for the prediction of far-field pattern characteristics of phased array fed reflector antennas by modeling only a small part of the array. In this approach, the simulated EEPs of the FPA are modeled as the phase-shifted versions of the simulated embedded element pattern (EEP) of the central element, and thereafter combined with the optimum weighting coefficients in order to find the total pattern of the feed. Although, the EEPs of dense array antennas are generally not identical (due to the array antenna mutual coupling and edge truncation effects), for typical FPA excitation scenarios, where the array edge elements have relatively low weights to produce the desired illumination of the reflector, this simplified approach has been found sufficiently accurate.
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| 6. |
- Lagovsky, B. A., et al.
(författare)
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Increasing accuracy of angular measurements using UWB signals
- 2017
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Ingår i: 2017 11th European Conference on Antennas and Propagation, EUCAP 2017. - : Institute of Electrical and Electronics Engineers (IEEE). - 9788890701870 ; , s. 1083-1086
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Konferensbidrag (refereegranskat)abstract
- We show that dispersion characteristics of antenna patterns should be taken into account when developing systems using UWB signals. The accuracy of measurement of angular coordinates of objects using UWB pulses is increased by optimizing their shape based on known characteristics of the antenna system and at least partially known characteristics of the investigated signal source. Optimization algorithms allow to minimize the width of the directional pattern for a given level of the useful signal.
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| 7. |
- Liu, Kexin, et al.
(författare)
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Broadband metasurface Luneburg lens antenna based on glide-symmetric bed of nails
- 2017
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Ingår i: 2017 11th European Conference on Antennas and Propagation, EUCAP 2017. - : Institute of Electrical and Electronics Engineers (IEEE). - 9788890701870 ; , s. 358-360
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Konferensbidrag (refereegranskat)abstract
- A broadband metasurface Luneburg lens based on glide-symmetric bed of nails is designed. First, the Luneburg lens was re-shaped using quasi-conformal transformation optics. With this technique, the original circular focal curve of the lens is changed to a straight line. Afterwards, the refractive index distribution of the optically transformed lens is realized by changing the height of the pins in a bed of nails configuration. The complete Luneburg lens is simulated in CST Microwave Studio and the results demonstrate that the lens has 8-16 GHz bandwidth.
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| 8. |
- Mansouri Moghaddam, Sadegh, 1987, et al.
(författare)
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Semi-omnidirectional dual-polarized wideband multiport antennas for MIMO applications in Random-LOS and RIMP
- 2017
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Ingår i: 2017 11th European Conference on Antennas and Propagation, EUCAP 2017. - 9788890701870 ; , s. 636-639
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Konferensbidrag (refereegranskat)abstract
- We present two configurations of multiport antennas for Multiple-input Multiple-output (MIMO) application. The configurations are comprised of three and four dual-polarized self-grounded bowtie antenna as the element, respectively. The MIMO performance of both antennas is evaluated in Random Line-of-Sight (Random-LOS) and Rich Isotropic Multipath (RIMP) channel models as two edge propagation environments. Both configurations provide 360° azimuth and 120° elevation angular coverage in Random-LOS and full sphere coverage in RIMP. Using digital threshold receiver model and Zero-Forcing receiver, the performances of both configurations are evaluated in terms of Probability of Detection (PoD) and MIMO multiplexing efficiency calculated at 95% PoD level. The simulated results show a good performance for both structures in two edge environments, which can be concluded as a good performance in a real life situation.
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| 9. |
- Miers, Zachary, et al.
(författare)
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Design of MIMO terminal antennas with user proximity using characteristic modes
- 2017
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Ingår i: 2017 11th European Conference on Antennas and Propagation, EUCAP 2017. - 9788890701870 ; , s. 2649-2651
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Konferensbidrag (refereegranskat)abstract
- Although the classical Theory of Characteristic Modes allows an arbitrary structure to be analyzed prior to the implementation of physical feeds, structures containing dielectrics have so far received very little attention. Recently, a mesh perturbation method is proposed to remove internal resonances from the characteristic mode (CM) solution for lossy dielectrics obtained using the computationally efficient surface integral equation. Herein this method was applied to extract the CMs of a lossy structure consisting of a terminal chassis held in a user hand. These modes were then individually analyzed and a subset was chosen to design a MIMO antenna with not only very low correlation, but also low hand-induced losses.
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| 10. |
- Perez, Mauricio D., et al.
(författare)
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Microwave Sensors for New Approach in Monitoring Hip Fracture Healing
- 2017
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Ingår i: 2017 11th European Conference On Antennas And Propagation (EUCAP). - : IEEE. - 9788890701870 ; , s. 1838-1842
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Konferensbidrag (refereegranskat)abstract
- Cyber-Physical System (CPS) applications in lower-extremity bony-fracture rehabilitation systems require real-time biophysical data. Emerging and interesting solutions are microwave approaches that provide good contrast between hard and soft tissues and between local anomalies inside tissues. Preliminarily some contacting non-invasive planar methods have been investigated in their feasibility of detecting human tissues variations with promising results. In this work we introduce two new microwave planar sensors for a new approach of hip fracture healing follow-up tool. They are designed for improved resolution and penetration at frequencies between 1 to 3 GHz in detecting variations in bone, muscle or fat tissues that are expected during a rehabilitation process. The resonant devices are optimized using Frequency Domain Reflectometry and CST (R) environment and validated using clinical trials with volunteers. The new approach is validated using clinical trials with volunteers and patients. These outcomes further emphasize the feasibility of devising systems for fracture rehabilitation.
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| 11. |
- Rydholm, Tomas, 1991, et al.
(författare)
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Microwave tomographic image improvement by fitting to a Cole-Cole relaxation model
- 2017
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Ingår i: 2017 11th European Conference on Antennas and Propagation, EUCAP 2017. - 9788890701870 ; , s. 682-684
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Konferensbidrag (refereegranskat)abstract
- We have reconstructed microwave tomographic images of the Supelec breast phantom using our imaging fixture in combination with a multi-channel vector network analyzer. During this study we were able to recover images without the support of a priori information over a broad frequency range - 1100-1900 MHz. We then fitted the spectral values at each pixel within the field of view to a Cole-Cole curve and extracted the coefficients at each location. While the individual images at each frequency provided reasonably representations of the target permittivity and conductivity distributions, the fibroglandular features were generally quite blurred with the surrounding adipose region. However, several of the Cole-Cole coefficient plots provided a higher level of resolution for the inclusions. While there was a noticeably high level of artifacts outside of the breast phantom perimeter, the internal structures are quite representative of the target. This is one of the first Cole-Cole image fittings using broadband measurement data on an actual phantom and sets the stage for higher specificity imaging.
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| 12. |
- Vosoogh, Abbas, 1984, et al.
(författare)
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Wideband cavity-backed slot subarray with gap waveguide feed-network for D-band applications
- 2017
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Ingår i: 2017 11th European Conference on Antennas and Propagation, EUCAP 2017. - 9788890701870 ; , s. 207-209
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Konferensbidrag (refereegranskat)abstract
- A simple and wideband subarray for D-band applications is presented in this paper. The proposed multilayer subarray consists of 2 × 2 cavity-backed slot subarray fed by a ridge gap waveguide transmission line. The simulated results show that the proposed subarray has a relative impedance bandwidth of 22.5% with input reflection coefficient better than -10 dB over the 126-158 GHz frequency band. An array antenna consisting of 8 × 8 slots is designed with the proposed subarray. The simulation results of the proposed subarray and antenna are presented.
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| 13. |
- Wang, Lei, et al.
(författare)
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Wideband omnidirectional planar antenna with vertical polarization
- 2017
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Ingår i: 2017 11th European Conference on Antennas and Propagation, EUCAP 2017. - : Institute of Electrical and Electronics Engineers (IEEE). - 9788890701870 ; , s. 3865-3868
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Konferensbidrag (refereegranskat)abstract
- In this paper we propose a circular leaky wave-antenna with omnidirectional radiation in the H-plane. The design utilizes double-layered strips to create an end-fire antenna. A linear tapering of the stripes in the design endows the antenna with a 27% impedance bandwidth of 26.4-34.6 GHz. The antenna is vertically polarized with a cross polarization below -30 dB. The antenna has low gain variation in H-plane and it is compact as a planar structure. Furthermore, it can be easily fabricated and integrated by standard PCB processing techniques, which is very promising for applications such as base stations for wireless communication, spectrum monitoring and jamming systems.
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| 14. |
- Zhao, Kun, et al.
(författare)
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Evaluation of combined TIS for high order MIMO system in mobile terminal
- 2017
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Ingår i: 2017 11th European Conference on Antennas and Propagation, EUCAP 2017. - : Institute of Electrical and Electronics Engineers (IEEE). - 9788890701870 ; , s. 3684-3687
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Konferensbidrag (refereegranskat)abstract
- The maximum ratio combined total isotropic sensitivity (TIS) of high order MIMO system in a real phone prototype is presented in this paper. The value of combined TIS is estimated through antenna pattern combination and verified by experiments. The impact from the order of MIMO system, the propagation model and the user body effect are investigated.
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