Searched for: subject%3A%22leaky%255C+wave%22
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Zhang, H. (author)
In recent decades, dielectric lens antennas have been more and more adopted and developed for sensing and imaging applications at sub-millimeter (sub-mm) wavelengths because they can achieve high gain while keeping their physical size and weight acceptable at these wavelengths. More recently, as low-loss and low-cost lens materials have become...
doctoral thesis 2024
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Gu, Junhong (author), Stumpf, Martin (author), Neto, A. (author), Lager, I.E. (author)
A strictly causal numerical study of the pulsed operation of a weakly dispersive, leaky wave (LW) antenna is presented. The intricacies at the forefront of the electromagnetic (EM) field radiated from a gap-fed slot in a perfectly electrically conducting (PEC) sheet are evidenced for the first time. The radical effect of a free-space gap...
journal article 2024
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Beijnen, Laurens (author)
Distributed feeding in photo-conducting antennas (PCAs) leads to simple optical designs, less prone to overheating, as well to terahertz (THz) antennas that can operate non-dispersively over wide bandwidths. However, the efficient analysis of pulsed PCAs was so far limited to architectures characterized by feeds small with respect to the THz...
master thesis 2023
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Bechrakis Triantafyllos, Alexandros (author)
In the framework of this MSc thesis the analysis of core-shell leaky-wave lens antennas is presented, based on a combination of asymptotic and Physical Optics techniques. This study aims to develop an analysis approach which can be subsequently used for the optimization of the Fly’s Eye antenna concept, through enabling the investigation of...
master thesis 2023
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Mavropoulou, Alexandra (author)
In the framework of this MSc thesis, the analysis and design guidelines for part of the quasi-optical system of a proposed astronomical instrument, called TIFUUN, are presented. The TIFUUN instrument is an imaging spectrometer, planned to be placed in the ASTE telescope to perform ground-based astronomical observations in the mm-submm wavelength...
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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Stumpf, M. (author), Gu, Junhong (author), Lager, I.E. (author)
A causality preserving interpretation of the electromagnetic (EM) leaky-wave (LW) propagation in space and time is proposed for the first time. The Cagniard-deHoop (CdH) joint transform technique is applied for elucidating the relation between time-domain (TD) head waves (HWs), body waves (BWs), Cherenkov wave effects, and LWs. It is...
journal article 2023
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van Berkel, S.L. (author), Alonso Del Pino, M. (author), Jung-Kubiak, Cecile (author), Chattopadhyay, Goutam (author)
The development of a low focal number and low-mass lens antenna is presented that enables terahertz spectroscopy applications on ultracompact platforms. The antenna operates efficiently over a 20% fractional bandwidth, from 450 to 550 GHz, with a gain of 50 dBi at 500 GHz. The antenna consists of a hyperbolic silicon lens that is placed in a...
journal article 2023
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Hoogelander, M. (author), van Berkel, S.L. (author), Malotaux, E.S. (author), Alonso Del Pino, M. (author), Cavallo, D. (author), Spirito, M. (author), Llombart, Nuria (author)
This article presents the development of a focal plane array (FPA) for terahertz imaging applications with a near diffraction-limited resolution achieved through a very tight sampling of the focal plane. The antenna array is integrated with direct detectors in a 22-nm CMOS technology and operates from 200 to 600 GHz. The tight sampling of the...
journal article 2023
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Zhang, H. (author), Dabironezare, Shahab Oddin (author), Baselmans, J.J.A. (author), Llombart, Nuria (author)
Large format focal plane arrays (FPAs) of dielectric lenses are promising candidates for wide field-of-view submillimeter imagers. In this work, we optimize the scanning gain of such imagers via shaping lens surfaces. We develop an optimization procedure using a field correlation technique between the fields generated by a reflector on the...
journal article 2023
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van Schelven, R.M. (author), Syed, Waqas (author), Carluccio, G. (author), Doris, Kostas (author), de Graauw, Anton (author), Neto, A. (author), Cavallo, D. (author)
In this work, we investigate antenna architectures to implement dual-mode operation in phased array designs. Planar slot antenna elements are used in array configuration, in combination with artificial dielectrics layers (ADLs) located in the close proximity of the array, to achieve pattern shaping. The artificial dielectric superstrate...
journal article 2023
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GU, JUNHONG (author)
The primary goal of this study is to infer a time-domain (TD) counterpart of the frequency domain leaky wave. To reach this goal, a number of challenging problems will be tackled: (1) Develop adequate computational tools for performing detailed TD electromagnetic (EM) analyses via CST Studio simulations, the post-processing of the results...
master 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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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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Bosma, S. (author), van Rooijen, N. (author), Alonso Del Pino, M. (author), Llombart, Nuria (author)
We present a resonant leaky-wave lens antenna, fed by a circular waveguide with annular corrugations in the ground plane. The proposed leaky-wave feed reduces the impact of the spurious TM0 leaky-wave mode in all planes over a wide bandwidth while reducing assembly complexity compared to previous methods. The proposed leaky-wave antenna has...
journal article 2022
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Arias Campo, M. (author)
The expanding demand for high-speed wireless communications is pushing current networks and systems close to their limits. The use of sub-THz bands, where large bandwidth is available, is pointed out as one of the key strategies to cope with the huge amount of data transfer in the next Beyond 5G and 6G communications generations. Despite the...
doctoral thesis 2021
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Alonso Del Pino, M. (author), Bosma, S. (author), Jung-Kubiak, Cecile (author), Chattopadhyay, Goutam (author), Llombart, Nuria (author)
In this article, we propose a hybrid electromechanical scanning lens antenna array architecture suitable for the steering of highly directive beams at submillimeter wavelengths with field-of-views (FoV) of ±25°. The concept relies on combining electronic phase shifting of a sparse array with a mechanical translation of a lens array. The use...
journal article 2021
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Arias Campo, M. (author), Holc, Katarzyna (author), Weber, Rainer (author), De Martino, C. (author), Spirito, M. (author), Leuther, Arnulf (author), Bruni, Simona (author), Llombart, Nuria (author)
Thanks to the large bandwidth availability, millimeter and sub-millimeter wave systems are getting more attractive to be used in a wide range of applications, such as high-resolution radar or high-speed communications. In this contribution, a new lens antenna in-package solution is presented for the H-band (220320 GHz), including a wideband...
journal article 2021
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Arias Campo, M. (author), Carluccio, G. (author), Blanco, Darwin (author), Litschke, Oliver (author), Bruni, Simona (author), Llombart, Nuria (author)
In this contribution, a broadband G-band leaky-wave (LW) fed lens antenna with an integrated dielectric grid polarizer is presented. The proposed wideband polarizer unit cell geometry enables its fabrication at frequencies higher than 100 GHz, presenting high transmission properties and low axial ratio (AR). A quasi-Analytic technique based...
journal article 2021
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Zhang, H. (author), Bosma, S. (author), Neto, A. (author), Llombart, Nuria (author)
A dual-polarized 4 x 4 scanning phased array antenna with leaky-wave enhanced lenses operating at 28 GHz is presented. Such an antenna can be used for point-to-point fifth-generation (5G) communications that require high gain, wide bandwidth (BW), and limited steering ranges. The proposed array has a periodicity of two wavelengths, and the...
journal article 2021
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