Searched for: subject%3A%22wideband%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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Ozzola, R. (author), Neto, A. (author), Imberg, Ulrik (author), Cavallo, D. (author)
We present a dual-polarized connected array of slots with an artificial dielectric layer (ADL) radome for mobile communication applications operating in the sub-6 GHz and the upper 6 GHz bands of 5G. The radiating slots are combined with two interchangeable ADL radomes with different thicknesses, targeting the bands 6-8 and 2-8 GHz,...
journal article 2024
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Coco Martin, C.M. (author), Hu, Weiya (author), Cavallo, D. (author)
This work aims to provide guidelines on the design of wideband flat lenses based on artificial dielectric layers (ADLs). Planar lenses based on metasurfaces are typically narrowband, due to the phase wrapping over the period of 2\pi that is strongly frequency-dependent. On the contrary, true-time-delay (TTD) planar lenses, which do not resort...
journal article 2024
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Javvaji, L.S. (author), Bolatkale, M. (author), Bajoria, Shagun (author), Rutten, Robert (author), Essink, Bert Oude (author), Beijens, Koen (author), Makinwa, K.A.A. (author), Breems, L.J. (author)
Advances in CMOS technologies and circuit techniques have led to the development of continuous-time delta-sigma modulators (CTΔ Σ Ms) that sample at gigahertz (GHz) frequencies and achieve high linearity [-100 dBc and >120 dBFS spurious-free dynamic ranges (SFDRs)] in wide bandwidths (>100 MHz). However, at low frequencies (≤ 10 MHz),...
journal article 2024
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Guendel, Ronny (author)
This thesis introduces the relevance of radar systems in the realm of human activity recognition (HAR) in Chapter 1. The study touches upon the complex understanding of continuous human activities and the existing challenges and gaps in current methodologies, hinting at the innovative technical approaches that are to be detailed in the following...
doctoral thesis 2023
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Beikmirza, M.R. (author)
The demand for faster mobile access and higher data throughput drives the evolution of wireless cellular communication, requiring larger modulation bandwidths and higher-order modulations and necessitating more efficient and flexible transmitter systems.<br/>Simultaneously, the advancements in nano-scale CMOS technologies have made transistors...
doctoral thesis 2023
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Singh, G.D. (author), Nemati, Hossein Mashad (author), Alavi, S.M. (author), de Vreede, L.C.N. (author)
This article presents an inverted Doherty power amplifier (IDPA) made load insensitive up to 2:1 voltage standing wave ratio (VSWR) across its fractional bandwidth with a very compact wideband impedance sensor embedded in its output power-combining network (OPCN). To correct for load variation, a low-loss tunable resonator (TR) is used to...
journal article 2023
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Cavallo, D. (author)
Artificial Dielectric Layers (ADLs) have recently been exploited to improve the radiation and impedance performance of integrated antennas at millimeter wave (mmWave) and terahertz (THz) frequencies. The ADLs are composed by layers of sub-wavelength periodic metal patches that can be arranged within a host medium to synthesize an equivalent...
conference paper 2023
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Hoogelander, M. (author), Alonso Del Pino, M. (author), Llombart, Nuria (author), Spirito, M. (author)
The continuous advancements in the coverage and sensitivity of terahertz direct-detector imagers places increasing constraints on the test benches needed for characterization. Already, relative differences on the order of a few decibels are observed between simulated and measured performance in the state-of-the-art literature. This...
conference paper 2023
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Tiberius, C.C.J.M. (author), Janssen, G.J.M. (author), Koelemeij, Jeroen (author), Dierikx, Erik (author), Diouf, C.E.V. (author), Dun, H. (author)
This paper presents a terrestrial networked positioning system that obtains a reliable time reference from a national time scale realization and distributes it in a prototype to six roadside base stations through a fiber-optic Gigabit Ethernet network. Wireless wideband signals are transmitted by the base stations, thereby enabling...
journal article 2023
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Mohammad Zaki, A.R. (author), Nihtianova, S. (author)
Small charge detection is used for a wide range of applications: advanced industrial process control, experimental physics and space instruments, and material testing and medical imaging. These applications give rise to the development of a wide variety of charge-sensitive readout integrated circuits (ROICs). The trend in the state-of-the-art...
conference paper 2023
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Beikmirza, M.R. (author), Shen, Y. (author), de Vreede, L.C.N. (author), Alavi, S.M. (author)
This article presents a wideband, energy-efficient digital transmitter (DTX) suitable for multi-mode/multi-band wireless communication applications. It features various operation modes comprising Cartesian (Modes-1/-2) and multi-phase (Modes-3/-4) configurations utilizing LO clocks with different duty cycle in the interleaving/non...
journal article 2023
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Montazerolghaem, M.A. (author), de Vreede, L.C.N. (author), Babaie, M. (author)
By introducing three different techniques, this article, for the first time, presents a wideband highly linear receiver (RX) capable of handling blocking scenarios in fifth-generation (5G) microcell base station applications. First, a parallel preselect filter is introduced to satisfy the base station co-location blocking requirements. Next,...
journal article 2023
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Chiasson, David (author), Lin, Yuan (author), Kok, M. (author), Shull, Peter (author)
Hyperbolic localization measures the time difference of arrivals (TDOAs) of signals to determine the location of a wireless source or receiver. Traditional methods depend on precise clock synchronization between nodes so that time measurements from independent devices can be meaningfully compared. Imperfect synchronization is often the dominant...
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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Liu, Changrui (author)
Relative localization (RL) is essential for the successful operation of micro air vehicle (MAV) swarms. Achieving accurate 3-D RL in infrastructure-free and GPS-denied environments with only distance information is a challenging problem that has not been satisfactorily solved. In this work, based on the range-based peer-to-peer RL using the...
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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Marting, Louis (author)
Terahertz astronomy has been exceptionally unexplored until the last decades due to a technological gap, but exactly at these wavelengths the most distant galaxies appear very bright. Efficient instruments that are capable of spectrometry are essential in understanding the physics of these distant objects. Within the framework of this thesis, an...
master thesis 2022
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Liu, Jiang (author)
In recent years, short-range reliable wireless system with high data rate and low power consumption has drawn sufficient attention and is in great demand in various applications. For biomedical implantable applications such as neural sensing and Brain-computer Interfaces (BCIs), due to the increasing number of sensing channels and elements, not...
master thesis 2022
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Tariq Alaa Mohamed Aziz Ibrahim, Tariq (author)
Wireless data traffic is projected to steadily increase in the near future, necessitating the demand for transceivers with higher linearity and efficiency. Digital power amplifiers have the potential to achieve these higher efficiency demands while digital pre-distortion can be used to improve their linearity. Digital pre-distortion requires a...
master thesis 2022
Searched for: subject%3A%22wideband%22
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