Searched for: subject%3A%22Antennas%22
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Tapia Barroso, Roderick (author)
Future communication scenarios will require massive Multiple-input multiple-output (MIMO) by the use of multi-beam antenna systems. Maximizing the number of beams for a given antenna size is paramount given that the space allocated to the antenna is often limited. This work aims at evaluating the maximum number of beams by analyzing the SIR in...
master thesis 2023
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Bosma, S. (author)
Millimeter- and submillimeter wave applications, such as point-to-point wireless communications in beyond-5G scenarios, long-range automotive radars and astronomy and astrophysics science cases from space require antennas with high-gain beams that are steerable. At lower (microwave) frequencies, fully sampled phased arrays with thousands of...
doctoral thesis 2023
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Mier Escurra, C. (author), Mor, A. R. (author), Vaessen, P.T.M. (author), Lathouwers, A.G.A. (author)
One of the main difficulties in measuring partial discharges (PD) in gas-insulated substations (GIS) is the overlapping of pulses at the sensor's location, which distorts the pulse resolution and the charge estimation. This research presents a new method called “synergy,” which identifies and suppresses reflections using magnetic and electric...
journal article 2023
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Gottmer, Leila (author)
In this thesis, an efficient optimization method is described for synthesizing lens antennas fabricated in low permittivity plastic materials to achieve wide scanning performances. The method is based on an antenna in reception representation. The optimized parameters are the location and orientation of the antenna feeder, lens angular region...
master thesis 2022
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Huiskes, Martijn (author)
Photoconductive antennas (PCAs) are an interesting candidate for imaging systems due to their relatively low cost and ability to provide a bandwidth of hundreds of GHz. The large bandwidth of PCAs allows for sub-millimeter depth resolution. However, the often-used single-element PCAs are intrinsically limited in the amount of power they can...
master thesis 2022
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Liu, Qinyu (author)
Since 2018, a race on 6G technology between many countries and institutions has started.<br/>As 6G mobile communication utilizes sub-THz frequency band, the antenna packaging requires higher level integration. Antenna in Package (AiP) is seen as a promising solution when it comes to the integration problem. At 100GHz operation frequency band,...
master thesis 2022
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Coco Martin, Caspar (author)
Planar lenses based on metasurfaces or resonant elements are typically narrowband due to phase wrapping, which is strongly frequency-dependent. On the contrary, true-time-delay (TTD) planar lenses, which do not resort to phase wrapping, can achieve large bandwidths. One convenient way to design wideband TTD lenses is by means of artificial...
master thesis 2022
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Birari, Natasha (author)
An exponential growth in the mobile communications industry over the past decade has raised concerns over it’s energy consumption, especially in light of the current climate crisis. 5G technologies in particular exhibit features that imply high power consumption, such as the densification of 5G base stations. Implementing mitigation measures...
master thesis 2022
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Xu, Bo Wen (author), Kamminga, Arjan (author)
A new antenna measurement setup, the Antenna Dome, is being developed, which can provide real time antenna and beamformer measurements. In order to be able to validate this setup, an existing beamforming system will be will be extensively studied and characterized. Multiple measurement setups will be used, providing multiple measured...
bachelor thesis 2022
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de Graaf, John (author), Mao, Rui (author)
In this thesis, the realization and qualification of an anechoic dome chamber for 5G antenna’s is discussed. As with audio, where no echoes or noise from outside is wanted when listening to music, when characterizing an antenna it must be prevented to get internal reflections or electromagnetic (EM) radiation from outside. For this reason, a...
bachelor thesis 2022
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Fiorellini Bernardis, A. (author)
In recent years, the interest in terahertz technology witnessed a constant increasing interest and attention from the scientific community, as it allows to unlock the THz bandwidth, that can be used for a wide range of applications: it helps the study of biological samples and help medical diagnostics; it serves as a harmless non-destructive...
doctoral thesis 2022
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Pascual Laguna, A. (author)
The mysteries of the early Universe are largely enshrouded in dust, product of the violent process of star formation. Due to the vast distances of our Universe, infrared light emitted by the heated dust back in those early stages can still be observed today, which has been observed to contribute to about half of the total cosmic background...
doctoral thesis 2022
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van Schelven, R.M. (author)
The fifth generation of mobile communication poses challenges in the form of increased data volume, network scalability and efficient network operation. An important part in meeting these requirements is the use of the mm-wave frequency range, enabling the use of a wide bandwidth and therefore the desired high-data rates. However, a challenging...
doctoral thesis 2022
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Ozzola, R. (author), Cavallo, D. (author), Neto, A. (author)
We present a study on beam coupling in radiating structures that support multiple simultaneous beams. The formation of multiple beams is relevant in modern wireless communication applications when diverse data streams can be sent from a single transmitter to users located in different directions. General expressions are provided that relate...
journal article 2022
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Mier Escurra, C. (author), Mor, A. R. (author)
Recent research has found that Magnetic loop antennas can detect partial discharges (PD) in gas-insulated substations (GIS); however, unbalanced shielded loop (UBSL) antennas are affected by electric field coupling. This research proposes a balanced shielded loop (BSL) adapted for GIS PD sensing with different designs. The frequency response and...
conference paper 2022
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Pascual Laguna, A. (author), Cavallo, D. (author), Baselmans, J.J.A. (author), Llombart, Nuria (author)
This communication proposes a broadband and efficient integrated focal plane array solution based on a near-field focused connected array of slots. The focused aperture provides: 1) broadband and highly efficient illumination of the quasi-optical system and 2) scanning capabilities within a focusing system. The connected array antenna in turn...
journal article 2022
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Aslan, Y. (author), Onat, N.B. (author)
The optimization of mode excitation coefficients in linear periodic arrays of multi-mode antenna elements is studied for grating lobe reduction. A novel beamforming architecture is proposed with a new optimization problem based on equi-amplitude element excitations for optimal power efficiency. The capabilities of the proposed synthesis approach...
conference paper 2022
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Bosma, S. (author), Neto, A. (author), Llombart, Nuria (author)
In this work, we show that the near field of leaky-wave resonant antennas (LWAs) radiating into a dense medium can be locally represented as a spherical wave in a certain solid angle around broadside using an accurate definition of the phase center. The near field in this solid angle can be efficiently evaluated through the integration of the...
journal article 2022
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Mohammadkarimi, M. (author), Dobre, Octavia A. (author), Win, Moe Z. (author)
Existing wireless communication systems have been mainly designed to provide substantial gain in terms of data rates. However, 5G and Beyond will depart from this scheme, with the objective not only to provide services with higher data rates. One of the main goals is to support massive machine-type communications (mMTC) in the Internet-of-Things...
journal article 2022
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Stumpf, Martin (author), Lager, I.E. (author), Antonini, Giulio (author)
Thin-wire structures in the presence or absence of a ground plane are analyzed numerically in the time domain (TD) with the aid of the Cagniard-DeHoop method of moments (CdH-MoM). It is demonstrated that the TD solution of such problems can be cast into the form of discrete time-convolution equations. Under the assumption of piecewise linear...
journal article 2022
Searched for: subject%3A%22Antennas%22
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