RF&MW - Grup de Recerca de Sistemes, Dispositius i Materials de RF i Microones
http://hdl.handle.net/2117/652
2016-05-30T20:32:15ZA large signal nonlinear MODFET model from small signal S-parameters
http://hdl.handle.net/2117/87376
A large signal nonlinear MODFET model from small signal S-parameters
O'Callaghan Castellà, Juan Manuel; Beyer, Jb
A general technique for predicting the MODFET large signal performance has been developed. The technique is based entirely on experimental data (small signal S-parameters at different biased points) and therefore is independent of the structure of the FET. Software requirements include a program to fit an equivalent circuit to S parameter data; a simple least-square polynomial approximation program; and SPICE for nonlinear time-domain simulations. Hardware requirements are basically limited to a network analyzer to carry out the small-signal S parameter measurements. Measurements at 10 GHz confirm the validity of the model.
2016-05-26T14:17:31ZO'Callaghan Castellà, Juan ManuelBeyer, JbA general technique for predicting the MODFET large signal performance has been developed. The technique is based entirely on experimental data (small signal S-parameters at different biased points) and therefore is independent of the structure of the FET. Software requirements include a program to fit an equivalent circuit to S parameter data; a simple least-square polynomial approximation program; and SPICE for nonlinear time-domain simulations. Hardware requirements are basically limited to a network analyzer to carry out the small-signal S parameter measurements. Measurements at 10 GHz confirm the validity of the model.Requirements for noise parameter measurements in superconducting electronic systems
http://hdl.handle.net/2117/87374
Requirements for noise parameter measurements in superconducting electronic systems
O'Callaghan Castellà, Juan Manuel
General considerations on the measurement of noise parameters in highly mismatched systems are discussed. In particular, the problem of noise characterization of active superconducting microwave devices is addressed. A measurement technique that includes an error analysis is presented along with current data for a superconducting flux flow transistor.
2016-05-26T14:15:44ZO'Callaghan Castellà, Juan ManuelGeneral considerations on the measurement of noise parameters in highly mismatched systems are discussed. In particular, the problem of noise characterization of active superconducting microwave devices is addressed. A measurement technique that includes an error analysis is presented along with current data for a superconducting flux flow transistor.PLL de microondas con tiempo de adquisición reducido
http://hdl.handle.net/2117/87318
PLL de microondas con tiempo de adquisición reducido
Berenguer Sau, Jordi; Artal, E.; Corbella Sanahuja, Ignasi; Comerón Tejero, Adolfo
The behaviour of a PLL where the VCO is injection-locked to the reference frequency is studied. It is experimentally shown that the phase acquisition time can be reduced relative to the non-injection locked VCO situation.
At the same time, the phase relationship between an injection-locked oscillator and the reference oscillator can also be fixed.
These techniques can be applied to the local oscillators synthesis in a coherent receiver for the 12.5, 20 and 30 GHz beacons of the Olympus satellite.
2016-05-25T13:20:54ZBerenguer Sau, JordiArtal, E.Corbella Sanahuja, IgnasiComerón Tejero, AdolfoThe behaviour of a PLL where the VCO is injection-locked to the reference frequency is studied. It is experimentally shown that the phase acquisition time can be reduced relative to the non-injection locked VCO situation.
At the same time, the phase relationship between an injection-locked oscillator and the reference oscillator can also be fixed.
These techniques can be applied to the local oscillators synthesis in a coherent receiver for the 12.5, 20 and 30 GHz beacons of the Olympus satellite.Multiplicadores de frecuencia para receptores coherentes de microondas
http://hdl.handle.net/2117/87273
Multiplicadores de frecuencia para receptores coherentes de microondas
Corbella Sanahuja, Ignasi; Berenguer Sau, Jordi; Pradell i Cara, Lluís; Comerón Tejero, Adolfo; Bará, J; Artal, E
The design of frequency multipliers using PLL techniques is presented in this article. The theory is dicussed and also experimental results of a x43 frequency multiplier with an output frequency of 11.4 GHz in wich excellent performance has been achieved.
2016-05-24T12:47:43ZCorbella Sanahuja, IgnasiBerenguer Sau, JordiPradell i Cara, LluísComerón Tejero, AdolfoBará, JArtal, EThe design of frequency multipliers using PLL techniques is presented in this article. The theory is dicussed and also experimental results of a x43 frequency multiplier with an output frequency of 11.4 GHz in wich excellent performance has been achieved.PLL de microondas con tiempo de adquisición reducido
http://hdl.handle.net/2117/87272
PLL de microondas con tiempo de adquisición reducido
Berenguer Sau, Jordi; Artal, E.; Corbella Sanahuja, Ignasi; Comerón Tejero, Adolfo
The behaviour of a PLL where the VCO is injection-locked to the reference frequency is studied. It is experimentally shown that the phase acquisition time can be reduced relative to the non-injection locked VCO situation.
At the same time, the phase relationship between an injection-locked oscillator and the reference oscillator can also be fixed.
These techniques can be applied to the local oscillators synthesis in a coherent receiver for the 12.5, 20 and 30 GHz beacons of the Olympus satellite.
2016-05-24T12:45:46ZBerenguer Sau, JordiArtal, E.Corbella Sanahuja, IgnasiComerón Tejero, AdolfoThe behaviour of a PLL where the VCO is injection-locked to the reference frequency is studied. It is experimentally shown that the phase acquisition time can be reduced relative to the non-injection locked VCO situation.
At the same time, the phase relationship between an injection-locked oscillator and the reference oscillator can also be fixed.
These techniques can be applied to the local oscillators synthesis in a coherent receiver for the 12.5, 20 and 30 GHz beacons of the Olympus satellite.A microstrip low cost, high performance, intruder radar detector
http://hdl.handle.net/2117/87251
A microstrip low cost, high performance, intruder radar detector
de los Reyes, Elías; Elias Fusté, Antonio; Ferrando, Miguel; Corbella Sanahuja, Ignasi
Doppler Radars operatinq as conventional intruder detectors at X band have been used in several security applications. However, almost all of them utilize heavy and bulky microwave subsystems in wavequide technoloqy. This paper presents a new prototype on microstrip technology for a homodyne doppler radar system wich exhibits excellent performance and low component cost.
2016-05-23T15:56:47Zde los Reyes, ElíasElias Fusté, AntonioFerrando, MiguelCorbella Sanahuja, IgnasiDoppler Radars operatinq as conventional intruder detectors at X band have been used in several security applications. However, almost all of them utilize heavy and bulky microwave subsystems in wavequide technoloqy. This paper presents a new prototype on microstrip technology for a homodyne doppler radar system wich exhibits excellent performance and low component cost.Amplificadores multietapa de bajo en las bandas de 20 y 30ghz
http://hdl.handle.net/2117/87111
Amplificadores multietapa de bajo en las bandas de 20 y 30ghz
Artal, E; Corbella Sanahuja, Ignasi; Busquets, C; Pradell i Cara, Lluís
Microstrip coupled lines technology has been used to design and built low noise amplifiers in 20 and 30 GHz bands. Active devices are GaAs MESFET and HEMT in chip form. The amplifiers have input and output waveguide interfaces, probe transitions between microstrip line and rectangular waveguide are described. Two three-stage low noise amplifiers, at 20 and 30 GHz respectively, are presented.
2016-05-17T12:52:37ZArtal, ECorbella Sanahuja, IgnasiBusquets, CPradell i Cara, LluísMicrostrip coupled lines technology has been used to design and built low noise amplifiers in 20 and 30 GHz bands. Active devices are GaAs MESFET and HEMT in chip form. The amplifiers have input and output waveguide interfaces, probe transitions between microstrip line and rectangular waveguide are described. Two three-stage low noise amplifiers, at 20 and 30 GHz respectively, are presented.Full wave analysis of the image hybrid dielectric/HTS resonator
http://hdl.handle.net/2117/87021
Full wave analysis of the image hybrid dielectric/HTS resonator
Sans, C; O'Callaghan Castellà, Juan Manuel; Sancho, D; Pous Andrés, Rafael; Fontcuberta, J; Ji-Fuh, Liang; Guo-Chun, Liang
An analysis of the image hybrid dielectric/HTS resonator is carried out. A full-wave radial mode-matching method is used to obtain the electromagnetic fields inside the resonator for single TE01 and dual HE11 modes. The resonator power-handling capability is estimated from the field at the surface of the HTS film, assuming a certain value for the critical field of the HTS film
2016-05-12T14:01:11ZSans, CO'Callaghan Castellà, Juan ManuelSancho, DPous Andrés, RafaelFontcuberta, JJi-Fuh, LiangGuo-Chun, LiangAn analysis of the image hybrid dielectric/HTS resonator is carried out. A full-wave radial mode-matching method is used to obtain the electromagnetic fields inside the resonator for single TE01 and dual HE11 modes. The resonator power-handling capability is estimated from the field at the surface of the HTS film, assuming a certain value for the critical field of the HTS filmOptimum carrier to signal power ratio for remote heterodyne DD-OFDM in PONs
http://hdl.handle.net/2117/86700
Optimum carrier to signal power ratio for remote heterodyne DD-OFDM in PONs
Cano Valadéz, Iván Nicolás; Santos Blanco, M. Concepción; Prat Gomà, Josep Joan
The carrier to signal power ratio (CSPR) in a directdetection
optical orthogonal frequency division multiplexing
(OFDM) system based on remote heterodyne scheme is optimized
in a passive optical network (PON) downlink. A numerical
investigation shows that nonlinearities in fiber have the effects
of increasing the optimum CSPR and making the system more
vulnerable to CSPR changes.
2016-05-06T12:51:55ZCano Valadéz, Iván NicolásSantos Blanco, M. ConcepciónPrat Gomà, Josep JoanThe carrier to signal power ratio (CSPR) in a directdetection
optical orthogonal frequency division multiplexing
(OFDM) system based on remote heterodyne scheme is optimized
in a passive optical network (PON) downlink. A numerical
investigation shows that nonlinearities in fiber have the effects
of increasing the optimum CSPR and making the system more
vulnerable to CSPR changes.Closed-form expressions for the optimization of high speed electro-optical modulators
http://hdl.handle.net/2117/86698
Closed-form expressions for the optimization of high speed electro-optical modulators
Ibarra Fusté, Jose Antonio; Santos Blanco, M. Concepción
Compact closed-form mathematical expressions for the propagation parameters (characteristic impedance,
effective permittivity and attenuation) of coplanar waveguides (CPW) are presented. The
formulas take into account asymmetric structures, thick electrodes and two-layered substrates, and
thus are perfectly tailored for the optimization of electro-optical modulators. Excellent agreements,
within a range of frequencies up to 100 GHz, are found with full-wave finite elements results from
commercial software (HFSS) and with measures reported in the literature, for material and geometrical
CPW parameters of practical relevance for the design of electro-optical modulators
2016-05-06T12:39:59ZIbarra Fusté, Jose AntonioSantos Blanco, M. ConcepciónCompact closed-form mathematical expressions for the propagation parameters (characteristic impedance,
effective permittivity and attenuation) of coplanar waveguides (CPW) are presented. The
formulas take into account asymmetric structures, thick electrodes and two-layered substrates, and
thus are perfectly tailored for the optimization of electro-optical modulators. Excellent agreements,
within a range of frequencies up to 100 GHz, are found with full-wave finite elements results from
commercial software (HFSS) and with measures reported in the literature, for material and geometrical
CPW parameters of practical relevance for the design of electro-optical modulators