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Robert J. Marks - One of the best experts on this subject based on the ideXlab platform.
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fast simultaneous optimization of power amplifier input power and load impedance for power added efficiency and adjacent channel power ratio using the power Smith tube
IEEE Transactions on Aerospace and Electronic Systems, 2016Co-Authors: Joseph Barkate, Matthew Fellows, Jennifer Barlow, Charles Baylis, Matthew Flachsbart, Zachary Hays, Lawrence Cohen, Robert J. MarksAbstract:Reconfigurable adaptive amplifiers are expected to be a critical component of future adaptive and cognitive radar transmitters. This paper details an algorithm to simultaneously optimize input power and load reflection coefficient of a power amplifier device to obtain the largest power-added efficiency (PAE) possible under a predefined constraint on adjacent-channel power ratio (ACPR). The vector-based search relies on estimation of the PAE and ACPR gradients in the three-dimensional power Smith tube. Accurate convergence to the optimum impedance in the Smith Chart is demonstrated in simulation and measurement search experiments requiring between 20 and 60 experimental queries. This paper presents a fast search to jointly optimize the input power level and load impedance. This method is feasible for future implementation in real-time reconfigurable power amplifiers.
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The Power Smith Tube: Joint Optimization of Power Amplifier Input Power and Load Impedance for Power-Added Efficiency and Adjacent Channel Power Ratio
2016Co-Authors: Joseph Barkate, Matthew Fellows, Jennifer Barlow, Charles Baylis, Robert J. MarksAbstract:Abstract-A new visualization tool for design is introduced: the Power Smith Tube. It provides aid in designing for optimum power-added efficiency (P AE) while meeting adjacent-channel power ratio (A CPR) requirements. The Power Smith Tube is a three-dimensional cylindrical extension of the Smith Chart with input power as the vertical axis. As such, this Smith Tube allows the visualization of design metrics, such as P AE and ACPR, as a function of both input power and load impedance. Performance of load-pull measurements or simulations at multiple values of input power provides data for the design. Design examples using the Power Smith Tube based on both simulation and measurement data are presented to demonstrate selection of load impedance and input power providing the highest P AE under ACPR constraints. Keywords- power-added efficiency, adjacent-channel power ratio, load-pull, power amplifiers, Smith Chart, optimization I
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the bias Smith tube simultaneous optimization of bias voltage and load impedance in power amplifier design
Radio and Wireless Symposium, 2016Co-Authors: Matthew Fellows, Jennifer Barlow, Charles Baylis, Joseph Barkate, Lawrence Cohen, Alexander Tsatsoulas, Sarvin Rezayat, Robert J. MarksAbstract:Multiple factors must be considered in power-amplifier design for wireless communications and radar, including bias voltage, input power, and load impedance. The Bias Smith Tube is presented as a three-dimensional extension of the Smith Chart with bias voltage as the vertical axis. It allows simultaneous visualization of nonlinear output characteristic behaviors over transistor bias voltage and load reflection coefficient. Simulated and measured three-dimensional surfaces of constant power-added efficiency (PAE), adjacent channel power ratio (ACPR), and delivered power are shown in the Bias Smith Tube, and a design approach is illustrated that finds the combination of load impedance and bias voltage providing maximum PAE under ACPR and/or delivered power constraints.
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the power Smith tube joint optimization of power amplifier input power and load impedance for power added efficiency and adjacent channel power ratio
Wireless and Microwave Technology Conference, 2015Co-Authors: Joseph Barkate, Matthew Fellows, Jennifer Barlow, Charles Baylis, Robert J. MarksAbstract:A new visualization tool for design is introduced: the Power Smith Tube. It provides aid in designing for optimum power-added efficiency (PAE) while meeting adjacent-channel power ratio (ACPR) requirements. The Power Smith Tube is a three-dimensional cylindrical extension of the Smith Chart with input power as the vertical axis. As such, this Smith Tube allows the visualization of design metrics, such as PAE and ACPR, as a function of both input power and load impedance. Performance of load-pull measurements or simulations at multiple values of input power provides data for the design. Design examples using the Power Smith Tube based on both simulation and measurement data are presented to demonstrate selection of load impedance and input power providing the highest PAE under ACPR constraints.
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the Smith tube selection of radar chirp waveform bandwidth and power amplifier load impedance using multiple bandwidth load pull measurements
Wireless and Microwave Technology Conference, 2014Co-Authors: Matthew Fellows, Jennifer Barlow, Charles Baylis, Matthew Flachsbart, Robert J. MarksAbstract:The operation of a radar system requires a trade-off between detection capabilities, power efficiency, and adjacent channel power minimization. Specifically, wide signal bandwidth is important for range detection. This paper presents how load-pull data taken for multiple linear frequency-modulated chirp waveforms with different bandwidths can be used to select the chirp waveform with the largest bandwidth possible, while meeting adjacent-channel power ratio and power-added efficiency requirements. This approach utilizes plots of adjacent-channel power ratio and power-added efficiency surfaces within a Smith tube, a three-dimensional, cylindrical extrapolation of the traditional Smith Chart. A measurement example is given to illustrate the design approach. This approach will be useful in the design of range radars, and also is likely to find use in enabling real-time reconfiguration of future radars for varying spectral environments and efficiency requirements.
Victor Asavei - One of the best experts on this subject based on the ideXlab platform.
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3d Smith Chart constant quality factor semi circles contours for positive and negative resistance circuits
IEEE Access, 2020Co-Authors: Victor Asavei, A. Muller, Alin Moldoveanu, Esther Sanabriacodesal, A M IonescuAbstract:The article firstly proves that the constant quality factor ( $Q$ ) contours for passive circuits, while represented on a 2D Smith Chart, form circle arcs on a coaxal circle family. Furthermore, these circle arcs represent semi-circles families in the north hemisphere while represented on a 3D Smith Chart. On the contrary, it then shows that, the constant $Q$ contours for active circuits with negative resistance form complementary circle arcs on the same family of coaxal circles in the exterior of the 2D Smith Chart. Moreover, we reveal that these constant $Q$ contours represent complementary semi-circles in the south hemisphere while represented on the 3D Smith Chart for negative resistance circuits. The constant $Q$ semi-circles implementation in the 3D Smith Chart computer aided design (CAD) tool is then successfully used to evaluate the quality factor variations of newly fabricated Vanadium dioxide inductors, directly from their reflection coefficient, as the temperature is increased from room temperature to 50 degrees Celsius (°C). Thus, a direct multi-parameter frequency dependent analysis is proposed including $Q$ , inductance and reflection coefficient for inductors. Then, quality factor direct evaluation is used for two tunnel diode small signal equivalent circuits analysis, allowing for the first time the direct analysis of the $Q$ and input impedance on a 3D Smith Chart representation of a circuit, while including negative resistance.
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3d Smith Charts scattering parameters frequency dependent orientation analysis and complex scalar multi parameter characterization applied to peano reconfigurable vanadium dioxide inductors
Scientific Reports, 2019Co-Authors: A. Muller, Alin Moldoveanu, Victor Asavei, Riyaz Abdul Khadar, Esther Sanabriacodesal, Anna Krammer, Montserrat Fernandezbolanos, Matteo Cavalieri, Junrui Zhang, Emanuele A CasuAbstract:Recently, the field of Metal-Insulator-Transition (MIT) materials has emerged as an unconventional solution for novel energy efficient electronic functions, such as steep slope subthermionic switches, neuromorphic hardware, reconfigurable radiofrequency functions, new types of sensors, terahertz and optoelectronic devices. Employing radiofrequency (RF) electronic circuits with a MIT material like vanadium Dioxide, VO2, requires appropriate characterization tools and fabrication processes. In this work, we develop and use 3D Smith Charts for devices and circuits having complex frequency dependences, like the ones resulting using MIT materials. The novel foundation of a 3D Smith Chart involves here the geometrical fundamental notions of oriented curvature and variable homothety in order to clarify first theoretical inconsistencies in Foster and Non Foster circuits, where the driving point impedances exhibit mixed clockwise and counter-clockwise frequency dependent (oriented) paths on the Smith Chart as frequency increases. We show here the unique visualization capability of a 3D Smith Chart, which allows to quantify orientation over variable frequency. The new 3D Smith Chart is applied as a joint complex-scalar 3D multi-parameter modelling and characterization environment for reconfigurable RF design exploiting Metal-Insulator-Transition (MIT) materials. We report fabricated inductors with record quality factors using VO2 phase transition to program multiple tuning states, operating in the range 4 GHz to 10 GHz.
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two compact Smith Charts the 3d Smith Chart and a hyperbolic disc model of the generalized infinite Smith Chart
Romanian Journal of Information Science and Technology, 2016Co-Authors: Andrei A Muller, Victor Asavei, Alin Moldoveanu, Esther Sanabriacodesal, D DascaluAbstract:The work of A. A. Muller was funded by the SIW-TUNE Marie Curie Integration Grant 322162 and the work of E. Sanabria-Codesal is partially supported by DGCYT grant number MTM2015-64013-P.
Sanabria-codesal Esther - One of the best experts on this subject based on the ideXlab platform.
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3D Smith Chart constant quality factor semi-circles contours for positive and negative resistance circuits
'Institute of Electrical and Electronics Engineers (IEEE)', 2020Co-Authors: Asavei Victor, Sanabria-codesal Esther, Moldoveanu Alin, Muller, Andrei A., Ionescu, Adrian. M.Abstract:The article proves first that the constant quality factor (Q) contours for passive circuits, while represented on a 2D Smith Chart, form circle arcs on a coaxal circle family. Furthermore, these circle arcs represent semi-circles families in the north hemisphere while represented on a 3D Smith Chart. On the contrary we show that the constant Q contours for active circuits with negative resistance form complementary circle arcs on the same family of coaxal circles in the exterior of the 2D Smith Chart. Also, we find out that these constant Q contours represent complementary semi-circles in the south hemisphere while represented on the 3D Smith Chart for negative resistance circuits. The constant Q - computer aided design (CAD) implementation of the Q semi-circles on the 3D Smith Chart is then successfully used to evaluate the quality factor variations of newly fabricated Vanadium dioxide inductors first, directly from their reflection coefficient, as the temperature is increased from room temperature to 50 degrees Celsius ({\deg}C). Thus, a direct multi-parameter frequency dependent analysis is proposed including Q, inductance and reflection coefficient for inductors. Then, quality factor direct analysis is used for two tunnel diode small signal equivalent circuits analysis, allowing for the first time the Q and input impedance direct analysis on Smith Chart representation of a circuit, including negative resistanceComment: 10 pages, 20 fig
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3D Smith Chart constant quality factor semi-circles contours for positive and negative resistance circuits
'Institute of Electrical and Electronics Engineers (IEEE)', 2020Co-Authors: Asavei Victor, Sanabria-codesal Esther, Moldoveanu Alin, Müller Andrei, Ionescu, Mihai AdrianAbstract:The article firstly proves that the constant quality factor (Q) contours for passive circuits, while represented on a 2D Smith Chart, form circle arcs on a coaxal circle family. Furthermore, these circle arcs represent semi-circles families in the north hemisphere while represented on a 3D Smith Chart. On the contrary, it then shows that, the constant Q contours for active circuits with negative resistance form complementary circle arcs on the same family of coaxal circles in the exterior of the 2D Smith Chart. Moreover, we reveal that these constant Q contours represent complementary semi-circles in the south hemisphere while represented on the 3D Smith Chart for negative resistance circuits. The constant Q semicircles implementation in the 3D Smith Chart computer aided design (CAD) tool is then successfully used to evaluate the quality factor variations of newly fabricated Vanadium dioxide inductors, directly from their reflection coefficient, as the temperature is increased from room temperature to 50 degrees Celsius (◦C). Thus, a direct multi-parameter frequency dependent analysis is proposed including Q, inductance and reflection coefficient for inductors. Then, quality factor direct evaluation is used for two tunnel diode small signal equivalent circuits analysis, allowing for the first time the direct analysis of the Q and input impedance on a 3D Smith Chart representation of a circuit, while including negative resistanc
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Smit's Chart and its Generalizations
'Universitat Politecnica de Valencia', 2019Co-Authors: Perez-peñalver M.jose, Sanabria-codesal Esther, Muller, Andrei A.Abstract:[EN] Smith's Chart is a graphical tool, classically used in the analysis and design of microwave circuits, based on the mathematical idea of inverting the positive semi-plane to the unit circle through the transformation of Möebius$M(z)=\frac{z-1}{z+1}.$ One of its main advantages is that it provides an excellent visual approach to high-frequency problems and, although its usefulness has survived to this day, it has some drawbacks that have been alleviated by successive generalizations. In Muller et al., 2011, the authors proposed a generalizationof Smith's Chart in space: the Smith 3D Chart, where they use the stereographic projection of the sphere in the plane. This new model unies the design of the circuits, keeping unchanged all the properties of the original Smith Chart. In addition, these authors developed a CAD tool www.3dSmithChart.com to facilitate the measurements and graphics in it. This is not the only possible generalization, in this work we present other possibilities using hyperbolic geometry. This geometry was explored by M. C. Escher, in some of his best known illustrations, as well as being closely related to original Smith's Chart (Gupta, 2006).[ES] La carta de Smith es una de la herramienta clásica en ingeniería de microondas, fue presentada por Philip Hagar Smith en 1939. Esta carta está basada en la idea matemática de invertir el semiplano positivo al círculo unitario a través de la transformación de Moëbius $M(z)=\frac{z-1}{z+1}.$ Una de sus ventajas principales es que proporciona un excelente enfoque visual de los problemas de microondas, aunque también tiene algunos inconvenientes, como que no se pueden representar dentro de la carta los coeficientes de reflexión mayores que 1.En 2011, A. A. Müller, P. Soto, D. Dascalu, D. Neculoiu y V. E. Boria propusieron una generalización de la carta de Smith en el espacio. En ella, los autores utilizan la proyección estereográfica de la esfera de Riemann en el plano. Este nuevo modelo unifica el diseño de los circuitos activos y pasivos con cualquier magnitud del coeficiente de reflexión del voltaje, manteniendo inalteradas todas las formas circulares del gráfico clásico de Smith. Además desarrollaron una herramienta CAD (www.3dSmithChart.com) para facilitar las mediciones y gráficos en esta carta.Esta no es la única generalización que se puede hacer, en este trabajo presentamos otras posibilidades utilizando la geometría hiperbólica. Este tipo de geometría fue explorada por Escher en algunas de sus más conocidas ilustraciones.Este trabajo ha sido parcialmente subvencionado por proyecto MTM2015-64013-P del Ministerio de Economía y Competitividad.Perez-Peñalver, M.; Sanabria Codesal, E.; Müller, AA. (2019). La carta de Smith y sus generalizaciones. Modelling in Science Education and Learning. 12(1):123-135. https://doi.org/10.4995/msel.2019.10990SWORD123135121P. H. Smith , Transmission-line calculator, Electronics, vol 12, pp. 29-31, 1939.P. H. Smith , Electronic Applications Of The Smith Chart, McGraw-Hill Book Company, 1969.C. Zelley, A spherical representation of the Smith Chart IEEE Microwave, vol 8, pp. 60-66, 2007.Y. Wu, Y. Liu, and H. Huang, Spherical Representation of the omnipotent Smith Chart, Microwave Opt. Technol. Lett., vol 50, no. 9, pp. 2452-2454, 2008.Y. Wu, Y. Liu, and H. Huang, , Theory of the spherical generalized Smith Chart, Microwave Opt. Technol. Lett., vol 51, no. 1 pp. 95-97, 2009.A. A. Muller, P. Soto, D. Dascalu, D. Neculoiu, and V. E. Boria, A 3-D Smith Chart base on the Riemann Spheres for Activ and Passive Microwave circuits, IEEE Microwave and Wireless Component Letters, vol 21, no. 6, pp. 286-288, 2011.A. A. Muller, P. Soto, D. Dascalu, D. Neculoiu, and V. E. Boria, The 3D Smith Chart and its practical applications, Microwave Journal, vol 5, no 7, pp. 64-74, 2012.A. A. Muller, E. Sanabria-Codesal, A. Moldoveanu, V. Asavei, P. Soto, V. E. Boria and S. Lucyszyn, Apollonius Unilateral Transducer Power Gain Circles on 3D Smith Charts, IET Electronics Letters, vol 50, no 21, pp. 1531-1533, 2014.A. A. Muller , E. Sanabria-Codesal, A. Moldoveanu , V. Asavei , S. Lucyszyn, Extended Capabilities of the 3-D Smith Chart With Group Delay and Resonator Quality Factor, IEEE Transactions on Microwave Theory and Techniques, vol 65, pp. 10-19,2017A. A. M uller y E. Sanabria-Codesal, A Hyperbololic Compact Generalized Smith Chart, Microwave Journal, Horizon House Publications, Inc., vol 59, pp. 90-94, 2016.Muller, Andrei A.,Sanabria-Codesal, E., Moldoveanu, A., Asavei, V., y Dascalu, D. Two Compact Smith Charts: The 3D Smith Chart and a Hyperbolic Disc Model of the Generalized Innite Smith Chart. SCIENCE AND TECHNOLOGY vol. 19, no 1-2,pp. 166-174, 2016.Perez-Peñalver, M., Sanabria-Codesal, E., Moldoveanu, F., Moldoveanu, A., Asavei, V., A Muller, A., y Ionescu, A. A Review and Mathematical Treatment of Innity on the Smith Chart, 3D Smith Chart and Hyperbolic Smith Chart. Symmetry, vol. 10, no 10, 458, 2018.M. Gupta, Escher's art, Smith Chart, and hyperbolic geometry, IEEE Microwave Magazine vol 7, no. 5, pp. 66-76, 2006.Brannan, D. A., Esplen, M. F., y Gray, J. J.. Geometry; Cambridge University Press: Cambridge, UK, 1999
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A Review and Mathematical Treatment of Infinity on the Smith Chart, 3D Smith Chart and Hyperbolic Smith Chart
'MDPI AG', 2018Co-Authors: Pérez Peñalver, María José, Sanabria-codesal Esther, Moldoveanu F., Moldoveanu Alin, Asavei Victor, Müller Andrei, Ionescu A.Abstract:[EN] This work describes the geometry behind the Smith Chart, recent 3D Smith Chart tool and previously reported conceptual Hyperbolic Smith Chart. We present the geometrical properties of the transformations used in creating them by means of inversive geometry and basic non-Euclidean geometry. The beauty and simplicity of this perspective are complementary to the classical way in which the Smith Chart is taught in the electrical engineering community by providing a visual insight that can lead to new developments. Further we extend our previous work where we have just drawn the conceptual hyperbolic Smith Chart by providing the equations for its generation and introducing additional properties.This research was partially funded by DGCYT grant number MTM2015-64013-P.Pérez Peñalver, MJ.; Sanabria-Codesal, E.; Moldoveanu, F.; Moldoveanu, A.; Asavei, V.; Müller, A.; Ionescu, A. (2018). A Review and Mathematical Treatment of Infinity on the Smith Chart, 3D Smith Chart and Hyperbolic Smith Chart. Symmetry (Basel). 10(10):1-13. https://doi.org/10.3390/sym10100458S113101
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A Review and Mathematical Treatment of Infinity on the Smith Chart, 3D Smith Chart and Hyperbolic Smith Chart
'MDPI AG', 2018Co-Authors: Jose Perez-penalver Maria, Sanabria-codesal Esther, Moldoveanu Alin, Asavei Victor, Müller Andrei, Moldoveanu Florica, Ionescu AdrianAbstract:This work describes the geometry behind the Smith Chart, recent 3D Smith Chart tool and previously reported conceptual Hyperbolic Smith Chart. We present the geometrical properties of the transformations used in creating them by means of inversive geometry and basic non-Euclidean geometry. The beauty and simplicity of this perspective are complementary to the classical way in which the Smith Chart is taught in the electrical engineering community by providing a visual insight that can lead to new developments. Further we extend our previous work where we have just drawn the conceptual hyperbolic Smith Chart by providing the equations for its generation and introducing additional properties
Alin Moldoveanu - One of the best experts on this subject based on the ideXlab platform.
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3d Smith Chart constant quality factor semi circles contours for positive and negative resistance circuits
IEEE Access, 2020Co-Authors: Victor Asavei, A. Muller, Alin Moldoveanu, Esther Sanabriacodesal, A M IonescuAbstract:The article firstly proves that the constant quality factor ( $Q$ ) contours for passive circuits, while represented on a 2D Smith Chart, form circle arcs on a coaxal circle family. Furthermore, these circle arcs represent semi-circles families in the north hemisphere while represented on a 3D Smith Chart. On the contrary, it then shows that, the constant $Q$ contours for active circuits with negative resistance form complementary circle arcs on the same family of coaxal circles in the exterior of the 2D Smith Chart. Moreover, we reveal that these constant $Q$ contours represent complementary semi-circles in the south hemisphere while represented on the 3D Smith Chart for negative resistance circuits. The constant $Q$ semi-circles implementation in the 3D Smith Chart computer aided design (CAD) tool is then successfully used to evaluate the quality factor variations of newly fabricated Vanadium dioxide inductors, directly from their reflection coefficient, as the temperature is increased from room temperature to 50 degrees Celsius (°C). Thus, a direct multi-parameter frequency dependent analysis is proposed including $Q$ , inductance and reflection coefficient for inductors. Then, quality factor direct evaluation is used for two tunnel diode small signal equivalent circuits analysis, allowing for the first time the direct analysis of the $Q$ and input impedance on a 3D Smith Chart representation of a circuit, while including negative resistance.
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3d Smith Charts scattering parameters frequency dependent orientation analysis and complex scalar multi parameter characterization applied to peano reconfigurable vanadium dioxide inductors
Scientific Reports, 2019Co-Authors: A. Muller, Alin Moldoveanu, Victor Asavei, Riyaz Abdul Khadar, Esther Sanabriacodesal, Anna Krammer, Montserrat Fernandezbolanos, Matteo Cavalieri, Junrui Zhang, Emanuele A CasuAbstract:Recently, the field of Metal-Insulator-Transition (MIT) materials has emerged as an unconventional solution for novel energy efficient electronic functions, such as steep slope subthermionic switches, neuromorphic hardware, reconfigurable radiofrequency functions, new types of sensors, terahertz and optoelectronic devices. Employing radiofrequency (RF) electronic circuits with a MIT material like vanadium Dioxide, VO2, requires appropriate characterization tools and fabrication processes. In this work, we develop and use 3D Smith Charts for devices and circuits having complex frequency dependences, like the ones resulting using MIT materials. The novel foundation of a 3D Smith Chart involves here the geometrical fundamental notions of oriented curvature and variable homothety in order to clarify first theoretical inconsistencies in Foster and Non Foster circuits, where the driving point impedances exhibit mixed clockwise and counter-clockwise frequency dependent (oriented) paths on the Smith Chart as frequency increases. We show here the unique visualization capability of a 3D Smith Chart, which allows to quantify orientation over variable frequency. The new 3D Smith Chart is applied as a joint complex-scalar 3D multi-parameter modelling and characterization environment for reconfigurable RF design exploiting Metal-Insulator-Transition (MIT) materials. We report fabricated inductors with record quality factors using VO2 phase transition to program multiple tuning states, operating in the range 4 GHz to 10 GHz.
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two compact Smith Charts the 3d Smith Chart and a hyperbolic disc model of the generalized infinite Smith Chart
Romanian Journal of Information Science and Technology, 2016Co-Authors: Andrei A Muller, Victor Asavei, Alin Moldoveanu, Esther Sanabriacodesal, D DascaluAbstract:The work of A. A. Muller was funded by the SIW-TUNE Marie Curie Integration Grant 322162 and the work of E. Sanabria-Codesal is partially supported by DGCYT grant number MTM2015-64013-P.
Esther Sanabriacodesal - One of the best experts on this subject based on the ideXlab platform.
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3d Smith Chart constant quality factor semi circles contours for positive and negative resistance circuits
IEEE Access, 2020Co-Authors: Victor Asavei, A. Muller, Alin Moldoveanu, Esther Sanabriacodesal, A M IonescuAbstract:The article firstly proves that the constant quality factor ( $Q$ ) contours for passive circuits, while represented on a 2D Smith Chart, form circle arcs on a coaxal circle family. Furthermore, these circle arcs represent semi-circles families in the north hemisphere while represented on a 3D Smith Chart. On the contrary, it then shows that, the constant $Q$ contours for active circuits with negative resistance form complementary circle arcs on the same family of coaxal circles in the exterior of the 2D Smith Chart. Moreover, we reveal that these constant $Q$ contours represent complementary semi-circles in the south hemisphere while represented on the 3D Smith Chart for negative resistance circuits. The constant $Q$ semi-circles implementation in the 3D Smith Chart computer aided design (CAD) tool is then successfully used to evaluate the quality factor variations of newly fabricated Vanadium dioxide inductors, directly from their reflection coefficient, as the temperature is increased from room temperature to 50 degrees Celsius (°C). Thus, a direct multi-parameter frequency dependent analysis is proposed including $Q$ , inductance and reflection coefficient for inductors. Then, quality factor direct evaluation is used for two tunnel diode small signal equivalent circuits analysis, allowing for the first time the direct analysis of the $Q$ and input impedance on a 3D Smith Chart representation of a circuit, while including negative resistance.
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3d Smith Charts scattering parameters frequency dependent orientation analysis and complex scalar multi parameter characterization applied to peano reconfigurable vanadium dioxide inductors
Scientific Reports, 2019Co-Authors: A. Muller, Alin Moldoveanu, Victor Asavei, Riyaz Abdul Khadar, Esther Sanabriacodesal, Anna Krammer, Montserrat Fernandezbolanos, Matteo Cavalieri, Junrui Zhang, Emanuele A CasuAbstract:Recently, the field of Metal-Insulator-Transition (MIT) materials has emerged as an unconventional solution for novel energy efficient electronic functions, such as steep slope subthermionic switches, neuromorphic hardware, reconfigurable radiofrequency functions, new types of sensors, terahertz and optoelectronic devices. Employing radiofrequency (RF) electronic circuits with a MIT material like vanadium Dioxide, VO2, requires appropriate characterization tools and fabrication processes. In this work, we develop and use 3D Smith Charts for devices and circuits having complex frequency dependences, like the ones resulting using MIT materials. The novel foundation of a 3D Smith Chart involves here the geometrical fundamental notions of oriented curvature and variable homothety in order to clarify first theoretical inconsistencies in Foster and Non Foster circuits, where the driving point impedances exhibit mixed clockwise and counter-clockwise frequency dependent (oriented) paths on the Smith Chart as frequency increases. We show here the unique visualization capability of a 3D Smith Chart, which allows to quantify orientation over variable frequency. The new 3D Smith Chart is applied as a joint complex-scalar 3D multi-parameter modelling and characterization environment for reconfigurable RF design exploiting Metal-Insulator-Transition (MIT) materials. We report fabricated inductors with record quality factors using VO2 phase transition to program multiple tuning states, operating in the range 4 GHz to 10 GHz.
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two compact Smith Charts the 3d Smith Chart and a hyperbolic disc model of the generalized infinite Smith Chart
Romanian Journal of Information Science and Technology, 2016Co-Authors: Andrei A Muller, Victor Asavei, Alin Moldoveanu, Esther Sanabriacodesal, D DascaluAbstract:The work of A. A. Muller was funded by the SIW-TUNE Marie Curie Integration Grant 322162 and the work of E. Sanabria-Codesal is partially supported by DGCYT grant number MTM2015-64013-P.
