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Fiorellini Bernardis, A. (author), Sberna, P.M. (author), Neto, A. (author), Llombart, Nuria (author)Pulsed terahertz time-domain systems rely on antennas printed on photoconductive substrates (PCA), which show extremely fast conductivity transients when illuminated by femto-seconds laser pulses. This work introduces a time domain representation of the PCA transmitter that accounts for time evolving voltages at the terminals of the...conference paper 2019
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Zhang, H. (author), Dabironezare, Shahab Oddin (author), Carluccio, G. (author), Neto, A. (author), Llombart, Nuria (author)In this work, a free accessible MATLAB interface is presented to analyze antenna-coupled Quasi-Optical (QO) systems in reception. This goal is achieved by using Fourier Optics (FO) and Geometrical Optics (GO) based methods. Specifically, the FO method represents the field focalized by a QO component on its focal plane as a plane wave spectrum...conference paper 2019
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Fiorellini Bernardis, A. (author), Sberna, P.M. (author), Neto, A. (author), Llombart, Nuria (author)Recently, powerful, reliable and cost-effective THz radiation photoconductive-emitters have been developed, providing up to 1mW of pulsed power in the range of frequencies between 0.1 and 0.7THz. In this paper we study the potential use of such sources for future pulsed radar systems aiming at stand-off imaging applications. Specifically, we...conference paper 2019
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van Berkel, S.L. (author), Malotaux, E.S. (author), Spirito, M. (author), Cavallo, D. (author), Neto, A. (author), Llombart, Nuria (author)A 12-pixel THz Focal Plane Array (FPA), integrated in Global Foundries 22nm CMOS technology, enabling high resolution passive THz imaging, is presented. The array efficiently couples blackbody radiation from 200 GHz to 600 GHz to Schottky Barrier Diodes (SBDs) in a differential topology. An antenna-detector co-design results in an average...conference paper 2019
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Garufo, A. (author), Sberna, P.M. (author), Carluccio, G. (author), Freeman, Joshua R. (author), Bacon, David R. (author), Li, Lianhe (author), Baselmans, J.J.A. (author), Llombart, Nuria (author), Neto, A. (author)A pulsed photoconductive terahertz (THz) source is presented that is able to radiate milliwatt (mW) level average power over a large bandwidth, by exploiting both the optical and electrical properties of photoconductive sources and the ultrawideband properties of connected antenna arrays. An optical system composed of a microlenses array...journal article 2019
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Llombart, Nuria (author), Dabironezare, Shahab Oddin (author), Carluccio, G. (author), Freni, Angelo (author), Neto, A. (author)Passive imaging cameras at millimeter and submillimeter wavelengths are currently entering a new era with the development of large format arrays of direct detectors. Several of these arrays are being developed with bare absorbing meshes without any antenna coupling (lens or horn) structures. The design of such arrays is typically done...journal article 2018
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Garufo, A. (author), Carluccio, G. (author), Freeman, Joshua R. (author), Bacon, David R. (author), Llombart, Nuria (author), Linfield, Edmund H. (author), Davies, Alexander G. (author), Neto, A. (author)This second part of two papers' sequence presents the experimental validation of the Norton equivalent circuit model for pulsed photoconductive antennas (PCAs) provided in the first paper of the sequence. To this goal, different prototypes of photoconductive antenna sources have been manufactured and assembled. The average powers radiated and...journal article 2018
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Garufo, A. (author), Carluccio, G. (author), Llombart, Nuria (author), Neto, A. (author)A novel equivalent circuit for pulsed photoconductive sources is introduced for describing the coupling between the photoconductive gap and the antenna. The proposed circuit effectively describes the mechanism of feeding the antenna by the semiconductor when this latter is illuminated by a laser operating in a pulsed mode. Starting from the...journal article 2018
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Neto, A. (author), Llombart, Nuria (author), Freni, Angelo (author)In this paper, the portion of the incident field that can be received by an antenna is investigated: the observable field. This field can be estimated relying only on the volume allocated to the antenna and thus independently of the specific antenna geometry. The observable field is composed by a single spherical wave that first converges...journal article 2018
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van Berkel, S.L. (author), Malotaux, E.S. (author), Cavallo, D. (author), Spirito, M. (author), Neto, A. (author), Llombart, Nuria (author)The optical performance of a wideband double bowtie slot antenna, implemented in 28nm CMOS technology, is evaluated. The antenna serves as a verification antenna for an uncooled single-pixel radiometer operating from 200 GHz to 600 GHz. The performance is evaluated in terms of radiometric pattern that is derived from the measured radiation...conference paper 2018
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Yurduseven, O. (author), Bueno Lopez, J. (author), Yates, Stephen (author), Neto, A. (author), Baselmans, J.J.A. (author), Llombart, Nuria (author)There is an increasing demand for large format detector arrays with large bandwidths and high antenna efficiencies for future THz astronomical radiometric applications. For direct detection instruments, it is also desired to have antennas with dual polarization reception in order to increase the received power from incoherent sources, thereby...journal article 2018
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Baselmans, J.J.A. (author), Bueno Lopez, J. (author), Yurduseven, O. (author), Yates, S. (author), Llombart, Nuria (author), Murugesan, V. (author), Thoen, David (author), Baryshev, AM (author), Endo, A. (author), Driessen, E.F.C. (author), Neto, A. (author)Astronomical observations at infrared, sub-millimetre, and millimetre wavelengths are essential for addressing many of the key questions in astrophysics. Future ground- and space based observatories need large detector arrays with a sensitivity limited only by the noise of the radiation background. We demonstrate that antenna coupled Microwave...poster 2018
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van Berkel, S.L. (author), Yurduseven, O. (author), Freni, Angelo (author), Neto, A. (author), Llombart, Nuria (author)In millimeter and submillimeter-wave radiometric imaging systems, a persistent goal is the increase in the speed of acquisition of the image while maintaining a high sensitivity. Typically, the highest sensitivity is achieved by cryogenically cooling the detectors, specifically in astronomical applications. However, for the purpose of low...journal article 2017
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Bueno Lopez, J. (author), Yurduseven, O. (author), Yates, S.J.C. (author), Llombart, Nuria (author), Murugesan, V. (author), Thoen, David (author), Baryshev, A.M. (author), Neto, A. (author), Baselmans, J.J.A. (author)We present the design, fabrication, and full characterisation (sensitivity, beam pattern, and frequency response) of a background limited broadband antenna coupled kinetic inductance detector covering the frequency range from 1.4 to 2.8 THz. This device shows photon noise limited performance with a noise equivalent power of 2.5 × 10<sup>-19<...journal article 2017
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Dabironezare, Shahab Oddin (author), Neto, A. (author), Llombart, Nuria (author)Passive imaging cameras at sub-millimeter wave-lengths are currently entering a new era with the development of large format arrays of direct detectors. Several of these arrays are being developed with bare absorbing meshes without any antenna coupling (lens or horn) structures. This paper uses a spectral electromagnetic model to analyze the...conference paper 2017
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Garufo, A. (author), Carluccio, G. (author), Freeman, Joshua R. (author), Bacon, David R. (author), Llombart, Nuria (author), Davies, Alexander G. (author), Neto, A. (author)In this paper a rigorous electromagnetic characterization of the setup for measuring the THz power radiated by pulsed photoconductive antenna is discussed. Such characterization is expressed in terms of efficiencies which quantify how much power is lost in the coupling between the various components involved in the measurement setup. The...conference paper 2017
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Bueno Lopez, J. (author), Yurduseven, O. (author), Llombart, Nuria (author), Yates, S.J.C. (author), Neto, A. (author), Baselmans, J.J.A. (author)This contribution presents the design and sub-mm wave measurements of a wideband dual polarized leaky lens antenna coupled to kinetic inductance detector (KIDs) to be specifically used for tightly spaced focal plane arrays. The antenna is planar and composed by two crossed slots, fed by two orthogonal coplanar waveguide (CPW) lines. In...conference paper 2017
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Yurduseven, O. (author), Bosma, S. (author), Endo, A. (author), Neto, A. (author), Llombart, Nuria (author)DESHIMA (Deep Spectroscopic High-redshift Mapper) is an instrument aiming at efficiently making spectroscopic redshift measurements of sub-mm wave galaxies (SMGs), thereby providing about the formation and the evolution of stars and galaxies. The aim of this work is to provide a preliminary study into the design of a wideband leaky lens antenna...conference paper 2017
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van Berkel, S.L. (author), Malotaux, E.S. (author), Cavallo, D. (author), Spirito, M. (author), Neto, A. (author), Llombart, Nuria (author)The design and performance analysis are presented for a passive uncooled radiometer pixel suitable for integration in 28 nm CMOS technology. In the configuration a single wideband antenna, operating from 200 GHz to 600 GHz, is connected to a pn-junction diode. Including the antenna-detector impedance mismatch, the detector shows an average NEP...conference paper 2017
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Garufo, A. (author), Llombart, Nuria (author), Neto, A. (author)In this paper, the performance of logarithmic spiral antennas as feeds of dense dielectric lens are investigated in detail. The performances are evaluated in terms of clean symmetric radiation patterns, high polarization purity, antenna efficiency, and radiation dispersivity. A logarithmic spiral antenna placed in the dielectric-air interface...journal article 2016