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Lopes Marta da Costa, T.M. (author), Shi, Chen (author), Tien, Kevin (author), Elloian, Jeffrey (author), A. Cardoso, Filipe (author), Shepard, Kenneth (author)Emerging non-imaging ultrasound applications, such as ultrasonic wireless power delivery to implantable devices and ultrasound neuromodulation, require wearable form factors, millisecond-range pulse durations and focal spot diameters approaching 100 μm with electronic control of its three-dimensional location. None of these are compatible...journal article 2021
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Van Katwijk, Alexander J. (author), Neto, A. (author), Toso, Giovanni (author), Cavallo, D. (author)We present the unit cell design of a wideband wide-scanning phased array operating in both Ku- and Ka-bands, for satellite communication applications. The radiating elements are dual-polarized connected slots loaded with an artificial dielectric superstrate, acting as a wide angle impedance matching (WAIM) structure. The design of the multi...conference paper 2020
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Yepes Julia, C. (author)In recent years, radar systems and satellite communications require phased array antennas that are capable of incorporating frequency and angular selectivity while maintaining a low profile. Active phased array antennas must comply with stringent requirements in terms of sensitivity to interference caused by other nearby radiating systems,...doctoral thesis 2020
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Aslan, Y. (author), Puskely, J. (author), Roederer, A.G. (author), Yarovoy, Alexander (author)The effect of forming single and multi-lobe beam<br/>patterns at mm-wave base station antennas on the received signal<br/>strength and co-channel interference is studied for mm-wave urban outdoor environments. A sample, simplified urban city model is used with randomly selected user positions. Ray tracing simulations are performed to analyze the...conference paper 2020
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Anand, C. (author), Delrue, Steven (author), Jeong, Hyunjo (author), Shroff, Sonell (author), Groves, R.M. (author), Benedictus, R. (author)Phased array ultrasonic testing is widely used to test structures for flaws due to its ability to produce steered and focused beams. The inherent anisotropic nature of some materials, however, leads to skewing and distortion of the phased array beam and consequently measurement errors. To overcome this, a quantitative model of phased array...journal article 2020
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Anand, C. (author), Groves, R.M. (author), Shroff, S. (author), Benedictus, R. (author)In this paper we ultrasonic signals from array transducers are simulated using the Thompson and Gray measurement model. The measurement model consists of a beam model, a system efficiency factor which characterizes the response of the electro-mechanical and electrical components of the system, and a flaw scattering model. To inspect layered...conference paper 2020
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Jakubczak, Patryk (author), Nardi, D. (author), Bienas, Jaroslaw (author), Sinke, J. (author)The manufacturing of Fibre Metal Laminates, consisting of alternating layers of pre-preg fibre and metal is complex, and defects can be introduced during manufacturing. The automation of the manufacturing steps is vital for future Glare production, and specific defects have to be considered. Among them, gaps between pre-preg plies represent a...journal article 2019
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Van Katwijk, Alexander J. (author), Cavallo, D. (author)Connected arrays of slots loaded with artificial dielectric layers have been proposed to realize wideband phased arrays with large scan capability. The role of the artificial dielectric superstrate is to provide a wide angle impedance matching transformation from the impedance at the feeding port of the unit cell to the free space impedance....conference paper 2019
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Akbar, F.S. (author), Ligthart, L.P. (author), Hendrantoro, Gamantyo (author), Lager, I.E. (author)The scanning performance of wide-angular scanning linear arrays is primarily degraded by the limited angular profile of the employed elements' patterns. This paper introduces an innovative strategy for compensating this degradation by using subarrays. Our design uses a uniform linear array with half-wavelength spaced elements, supplemented by...journal article 2019
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Aslan, Y. (author), Puskely, J. (author), Roederer, A.G. (author), Yarovoy, Alexander (author)Minimization of the maximum sidelobe level for a given array geometry, amplitude distribution, and nulling sectors by phase-only adjustment of the element coefficients is studied. Nonlinear optimization problem for phase distribution is solved using a novel iterative convex optimization algorithm, which includes mutual coupling effects and...journal article 2019
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Hänsel, A. (author)Spectroscopy is a powerful tool to investigate the physical properties of complex systems. The interaction of light with matter allows to get insights into the structure of it. Chapter 1 is dedicated to introduce this topic and to show the developments of the technologies that paved the way to its success. Special focus is given to the...doctoral thesis 2018
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Yepes Julia, C. (author), Cavallo, D. (author), Gandini, E. (author), Monni, Stefania (author), Neto, A. (author), van Vliet, Frank E. (author)A five-layer frequency selective surface (FSS) composed of subwavelength elements with large harmonic rejection bandwidth is presented. The FSS design is based on an equivalent circuit model, where the interlayer interaction is only described with a single transmission line representing the fundamental Floquet wave. A prototype of the...journal article 2018
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Aslan, Y. (author), Puskely, J. (author), Roederer, A.G. (author), Yarovoy, Alexander (author)A convex iterative algorithm for the synthesis of uniform amplitude, space-tapered linear phased arrays with simultaneous multiple beam optimization for 5G applications is presented. The performance of the algorithm is demonstrated by the synthesis of two arrays having 16 and 24 elements with 60 and 90 degree scan range, respectively. The effect...conference paper 2018
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Puskely, J. (author), Aslan, Y. (author), Roederer, A.G. (author), Yarovoy, Alexander (author)In this paper, we present a 5G base station phased antenna array concept based on the power equalization in the elevation cut. We designed aperture coupling microstrip patch array exploiting a substrate integrated waveguide structure as feeding line for realization of the cosecant radiation pattern in elevation cut. The antenna is designed to be...conference paper 2018
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Fool, F. (author), de Wit, J. (author), Vos, H.J. (author), Bera, D. (author), de Jong, N. (author), Verweij, M.D. (author)The huge amount of data that needs to be transferred between probe and imaging system becomes a major issue when the data transfer capacity is limited, e.g. in handheld systems, wireless probes and miniaturized probes. The amount of data can be significantly reduced by using two-stage beamforming. The first stage consists of a fixed focus...conference paper 2018
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Fortunato, J. (author), Anand, C. (author), Braga, Daniel F.O. (author), Groves, R.M. (author), Moreira, P. M.G.P. (author), Infante, V (author)Weight reduction is an important driver of the aerospace industry, which encourages the development of lightweight joining techniques to substitute rivet joints. Friction stir welding (FSW) is a solid-state process that enables the production of lighter joints with a small performance reduction compared to the base material properties....journal article 2017
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Haider, S.N. (author), Yarovoy, Alexander (author), Roederer, A.G. (author)A frequency reconfigurable phased array element is presented. The operational band of the single port L/S-band antenna can be selected by modifying the element apertures with p-I-n diode switches. The antenna element satisfies strict requirements on its frequency band separation (2.2:1), size, feeding structure and control lines to be...journal article 2017
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- Gentile, G. (author) doctoral thesis 2016
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Puskely, J. (author), Yarovoy, Alexander (author), Roederer, A.G. (author)A novel two-port, dual-band square-ring microstrip antenna element for wide-angle scanning planar phased array is proposed. The two ports are used to operate the antenna array over the L and S radar bands. Microstrip square-ring radiators are chosen due to their smaller dimensions compared to the conventional microstrip patch. To extend...conference paper 2016
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Blanco, D. (author), Rajo-Iglesias, E. (author), Montesano, A. (author), Llombart, Nuria (author)We present a practical implementation of a leaky-wave thinned phased array in printed circuit board (PCB) technology. In this paper, we demonstrate that a reduction of the grating lobes, and therefore an improved gain in a thinned phased array, with respect to standard solutions, is achieved by virtue of the angular filtering introduced by a...journal article 2016