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  • Grup de Teledetecció, Antenes, Microones i Superconductivitat

     Aguasca Sole, Alberto; Barlabe Dalmau, Antoni; Blanch Boris, Sebastian; Broquetas Ibars, Antoni; Camps Carmona, Adriano Jose; Cardama Aznar, Angel; Elias Fuste, Antonio; Duffo Ubeda, Nuria; Fabregas Canovas, Francisco Javier; Jofre Roca, Luis; Heldring, Alexander; López Martínez, Carlos; Mallorqui Franquet, Jordi Joan; O'callaghan Castella, Juan Manuel; Pradell Cara, Lluis; Rius Casals, Juan-manuel; Romeu Robert, Jordi; Torres Torres, Francisco; Ubeda Farre, Eduardo; Vall-llossera Ferran, Mercedes Magdalena; Duran Martinez, Israel; Wu, Lin; Gilasgar, Mitra; Lort Cuenca, Marc; Imbert Villa, Marc; Martin Alemany, Francisco; Chaparro Danon, David; Pablos Hernandez, Miriam; Pascual Biosca, Daniel; Park, Hyuk; Alonso Arroyo, Alberto; Onrubia Ibañez, Raul; Yam Ontiveros, Luis Eduardo; Rodriguez Silva, Juan Carlos; Piles Guillem, Maria; Deng, Xinping; Querol Borras, Jorge; Corbella Sanahuja, Ignasi
    Competitive project

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  • Multimodal Microwave Filters  Open access

     Contreras Lizarraga, Adrian Arturo
    Department of Signal Theory and Communications, Universitat Politècnica de Catalunya
    Theses

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    En esta tesis se presenta la concepción, diseño e implementación de nuevas topologías de resonadores y filtros de microondas multimodales, utilizando una combinación de tecnologías uniplanares como guía de onda coplanar (CPW), tiras coplanares (CPS) y slotlines. El término "multimodal" se refiere a circuitos uniplanares CPW donde los dos modos fundamentales se propagan (el modo par y el modo impar). Mediante el uso de ambos modos de la CPW, es posible lograr funciones adicionales, tales como generar ceros de transmisión para incrementar el rechazo ó para atenuar frecuencias armónicas, mejorando el rechazo fuera de banda del filtro. Por otra parte, se demostró que mediante el uso de circuitos multimodales es posible reducir la longitud de un filtro convencional hasta 80%. Además de filtros pasobanda se presentan nuevas topologías de filtros de banda eliminada. Los filtros de banda eliminada propuestos hacen uso de resonadores multimodales de onda lenta (slow-wave) para disminuir el área total de los filtros.Este trabajo también abarca el desarrollo de técnicas de síntesis para cada filtro multimodal propuesto. Las ecuaciones de diseño se obtuvieron a partir de circuitos multimodales generalizados disponibles en la literatura. Los circuitos multimodales han sido adaptados para cada caso y modelados como componentes basicos de filtros, tales como inversores de impedancia/admitancia ó elementos concentrados. Mediante el uso de las ecuaciones propuestas, es posible diseñar filtros con una respuesta y ancho de banda predeterminado . El uso de la síntesis propuesta permite un rápido análisis y diseño de filtros multimodales, utilizando simuladores de circuitos de RF comerciales.Adicionalmente, se han demostrado varias topologias de filtros reconfigurables y sintonizables, utilizando dispositivos activos (diodos PIN y varactores) ó MEMS de RF. Estas nuevas topologías demuestran la flexibilidad de los circuitos multimodales. Para poder implemenatar los filtros sintonizables basados en MEMS de RF, se han diseñados , fabricado y medido diferentes conmutadores capacitivos y óhmicos. Como un ejemplo de los grados de libertad adicionales de los circuitos multimodales, se ha diseñado por primera vez un filtro reconfigurable que utiliza puentes de equipotencialidad conmutables, utilizando MEMS de RF.

    This thesis presents the conception, design and implementation of new topologies of multimodal microwave resonators and filters, using a combination of uniplanar technologies such as coplanar waveguide (CPW), coplanar strips (CPS) and slotlines. The term "multimodal" refers to uniplanar circuits in which the two fundamental modes of the CPW propagate (the even and the odd mode). By using both modes of the CPW, it is possible to achieve added functions, such as additional transmission zeros to increase the rejection, or to attenuate harmonic frequencies to improve the out-of-band rejection. Moreover, it is demonstrated that by using multimodal circuits, it is possible to reduce the length of of a conventional filter up to 80%. In addition to bandpass filters, new topologies of compact band-stop filters are developed. The proposed band-stop filters make use of slow-wave resonators to decrease the total area of the filters and achieve compact topologies. This work also addresses the development of synthesis techniques for each multimodal filter. The design equations were obtained from generalized multimodal circuits available in the literature, which have been adapted for each particular case and modeled as basic filter components, such as immitance inverters or lumped elements. By using the proposed synthesis equations, it is possible to design filters with a desired response and relative bandwidth. The use of the proposed synthesis enables a fast analysis and design of multimodal filters using circuit simulators. As an added feature, several reconfigurable and tunable filter topologies were demonstrated, using active devices (PIN diodes and varactors) or RF-MEMS. These new topologies demonstrate the flexibility of multimodal circuits. For the RF-MEMS-based tunable filters, different capacitive and ohmic switches were designed, fabricated and measured. As an example of the additional degrees of freedom using of RF-MEMS and multimodal CPW circuits, a reconfigurable filter using RF-MEMS switchable air-bridges as a reconfiguration device has been demonstrated in this work for the first time.

  • Reconfigurable multimodal bandpass filter based on RF-MEMS switchable CPW air-bridges

     Contreras Bleda, Adrián; Casals Terre, Jasmina; Pradell Cara, Lluis; Giacomozi, Flavio; Iannacci, Jacopo; Ribó i Pal, Miquel
    European Microwave Week
    p. 328-331
    DOI: 978-2-87487-032-3
    Presentation's date: 2013-10-08
    Presentation of work at congresses

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    In this paper, a uniplanar RF-MEMS secondorder bandpass filter with reconfigurable centre frequency is presented. It is based on quarter-wavelength slotline resonators and CPW-slotline multimodal immittance inverters (MIIs), which are reconfigured using RF-MEMS switchable CPW airbridges (SABs). The filter can be adequately explained and designed using multimodal theory and circuit models. A surface micromachining process on high-resistivity silicon substrate was used to fabricate the filter. Experimental results show frequency reconfigurability from 12 GHz to 13 GHz, maintaining the same relative bandwidth, and insertion losses of 4.6 dB and 4.7 dB respectively.

  • Premio Jóvenes Científicos URSI 2013

     Gilasgar, Mitra; Barlabe Dalmau, Antoni; Pradell Cara, Lluis
    Award or recognition

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    A very low distortion high efficiency class-F power amplifier at 900 MHz.  Open access

     Gilasgar, Mitra; Barlabe Dalmau, Antoni; Pradell Cara, Lluis
    Simposium Nacional de la Unión Científica Internacional de Radio
    Presentation's date: 2013-09-12
    Presentation of work at congresses

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    This paper presents a novel class-F power amplifier for mobile applications in which with a proper harmonic tuning structure the need for an extra filtering section is eliminated. A class-F power amplifier employing a GaN HEMT device has been designed, fabricated and measured at 900 MHz. The fabricated circuit achieves an excellent harmonic-suppression level and the total harmonic distortion is around 1.2%. It overcomes the narrow band performance of class-F power amplifiers, giving more than 70% efficiency over a 100 MHz bandwidth. Experimental results show that the amplifier is able to deliver 38.5 dBm output power while achieving the state-of-the-art PAE of 80.5% with a peak drain efficiency of 84%, and a power gain of 13.6 dB for an input power of 25 dBm. A good agreement between measurement and simulation results is observed for the proposed structure.

    This paper presents a novel class - F power amplifier for mobile applications in which with a proper harmonic tuning structure the need f or an extra fil tering section is eliminated . A class - F power a mplifier employing a GaN HEMT device has been designed, fabricated and measured at 900 MHz . The fabricated circuit achieves a n excel lent harmonic - suppression level and the t otal h armonic distortion is around 1.2% . It overcomes the narrow band performance of class - F power amplifier s, giving more than 70% efficiency over a 100 MHz bandwidth . Experimental results show that the amplifier is able to deliver 38.5 dBm output power while achieving the state - of - the - art PAE of 8 0.5 % with a peak drain eff iciency of 8 4 % , and a power gain of 13.6 dB for an input power of 25 dBm . A good agreement between measurement and simulation results is observed for the proposed structure.

  • Reconfigurable uniplanar bandpass filter based on RF-MEMS switched capacitors

     Contreras Lizarraga, Adrián Arturo; Pradell Cara, Lluis; Casals Terre, Jasmina; Giacomozzi, Flavio; Iannacci, Jacopo; Ribó i Pal, Miquel
    International Symposium on RF MEMS and RF Microsystems
    Presentation's date: 2013-07-02
    Presentation of work at congresses

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    In this paper, an uniplanar RF-MEMS second-order bandpass filter with reconfigurable centre frequency is presented. It is based on half-wavelength slotline resonators, which are loaded using RF-MEMS switches connected to MIM capacitors. Experimental results show frequency reconfigurability from 15 GHz down to 10 GHz

    In this paper a reconfigurable bandpass filter is designed using ohmic-contact cantilever-type Micro Electro Mechanical Systems (MEMS) switches., Tthe filter can switch between two different states with a center frequency tunable range of 13 % in C band. The topology allows achieving two accurate center frequencies, each associated with a precisely defined bandwidth, using six MEMS ohmic-switches. The design carefully takes into account the external quality factor for both filter states to ensure a good impedance match at each frequency. Coupling coefficients and resonator lengths produce the bandwidths and center frequencies required by design specifications. The filter is designed to have center frequencies of 5.5 and 6.2 GHz, with a fractional bandwidth (FBW) of 5 and 3 %, respectively. Filter specifications were successfully met with the proposed topology. The filter was fabricated on a quartz substrate and measured responses are in good agreement with simulations

  • Frequency and bandwidth control of switchable microstrip bandpass filters using RF-MEMS ohmic switches

     Brito Brito, Zabdiel; Llamas Garro, Ignacio; Pradell Cara, Lluis; Giacomozzi, Flavio; Colpo, Sabrina
    International Symposium on RF MEMS and RF Microsystems
    Presentation's date: 2013-07-02
    Presentation of work at congresses

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    In this paper a reconfigurable bandpass filter is designed using ohmic-contact cantilever-type Micro Electro Mechanical Systems (MEMS) switches., Tthe filter can switch between two different states with a center frequency tunable range of 13 % in C band. The topology allows achieving two accurate center frequencies, each associated with a precisely defined bandwidth, using six MEMS ohmic-switches. The design carefully takes into account the external quality factor for both filter states to ensure a good impedance match at each frequency. Coupling coefficients and resonator lengths produce the bandwidths and center frequencies required by design specifications. The filter is designed to have center frequencies of 5.5 and 6.2 GHz, with a fractional bandwidth (FBW) of 5 and 3 %, respectively. Filter specifications were successfully met with the proposed topology. The filter was fabricated on a quartz substrate and measured responses are in good agreement with simulations

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    A RF-MEMS switchable CPW air-bridge  Open access

     Contreras Lizarraga, Adrián Arturo; Casals Terre, Jasmina; Pradell Cara, Lluis; Giacomozzi, Flavio; Colpo, Sabrina; Iannacci, Jacopo; Ribó i Pal, Miquel
    European Microwave Conference
    p. 441-444
    Presentation's date: 2012-10-30
    Presentation of work at congresses

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    This work presents a new shunt-Type ohmic contact RF-MEMS switch specifically designed as a switchable CPW air bridge. The switch can be used in coplanar waveguide (CPW) reconfigurable multimodal circuits, for a selective use of the CPW odd-mode. The bridge is anchored using folded-beam suspensions, in such a way that two points at each end of the bridge remain free to contact the ground planes of the CPW. The suspension has been designed to compensate stress gradients effects and to lower actuation voltage. In the actuated (ON) state, the switch isolation to the odd mode is better than 20dB up to 8GHz and 10dB up to 30GHz. 2012 European Microwave Assoc.

    This work presents a new shunt-type ohmic contact RF-MEMS switch specifically designed as a switchable CPW air bridge. The switch can be used in coplanar waveguide (CPW) reconfigurable multimodal circuits, for a selective use of the CPW odd-mode. The bridge is anchored using folded-beam suspensions, in such a way that two points at each end of the bridge remain free to contact the ground planes of the CPW. The suspension has been designed to compensate stress gradients effects and to lower actuation voltage. In the actuated (ON) state, the switch isolation to the odd mode is better than 20dB up to 8GHz and 10dB up to 30GHz.

    Postprint (author’s final draft)

  • Filtro paso-banda con control preciso de frecuencia central y ancho de banda usando interruptores RF MEMS

     Brito Brito, Zabdiel; Llamas Garro, Ignacio; Perruisseau Carrier, Julien; Pradell Cara, Lluis; Giacomozzi, Flavio; Colpo, Sabrina
    Simposium Nacional de la Unión Científica Internacional de Radio
    p. 1-4
    Presentation's date: 2012-09-12
    Presentation of work at congresses

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    In this paper a reconfigurable bandpass filter is presented. The filter is able to switch between two different states with a center frequency tunable range of 24 % in C band. Center frequency and bandwidth are precisely met by a switchable filter topology that includes two folded resonator extensions switched by four ohmic-contact cantilever-type Micro Electro Mechanical Systems (MEMS) switches. The filter was designed to have center frequencies of 5 and 6.2 GHz, with a fractional bandwidth of 7 and 3 %, respectively. The filter was fabricated on a quartz substrate and measured responses are in good agreement with simulations. Filter specifications were successfully met with the proposed topology.

    Postprint (author’s final draft)

  • Low voltage capacitive and Ohmic RF-MEMS Switches

     Contreras Lizarraga, Adrian Arturo; Casals Terre, Jasmina; Pradell Cara, Lluis; Giacomozzi, Flavio; Colpo, Sabrina; Iannacci, Jacopo; Ribó i Pal, Miquel
    International Symposium on RF MEMS and RF Microsystems
    Presentation's date: 2012
    Presentation of work at congresses

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    This work presents experimental results of capacitive and ohmic-contact RF-MEMS switches. The suspension has been designed to compensate stress-gradient effects, and to obtain low pull-in voltages. The measured actuation voltage is 12 V for devices with an air gap of 1.3 µm. The measured isolation of the capacitive switches is better than 20 dB for frequencies above 15 GHz, and better than 30 dB from 31 GHz up to 80 GHz according to simulations. The ohmic-contact switch can be used to control the odd mode in coplanar waveguide (CPW) reconfigurable multimodal circuits. The CPW odd-mode isolation of the ohmic-contact switch in its down state is better than 20 dB up to 8 GHz and better than 10 dB up to 30 GHz.

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    Conmutadores RF-MEMS de baja tensión  Open access

     Contreras Lizarraga, Adrian Arturo; Casals Terre, Jasmina; Pradell Cara, Lluis; Colpo, Sabrina; Iannacci, Jacopo; Ribó i Pal, Miquel; Giacomozzi, Flavio
    Simposium Nacional de la Unión Científica Internacional de Radio
    Presentation's date: 2012
    Presentation of work at congresses

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    This work shows experimental results of capacitive and ohmic RF-MEMS switches with low actuation voltage. The isolation of capacitive switches is better than 20 dB from 15 GHz and up to 80 GHz according to simulations. The ohmic-contact switch can be used in coplanar waveguide (CPW) reconfigurable multimodal circuits, for a selective use of the CPW odd-mode. The CPW odd-mode isolation in the down state is better than 20 dB up to 8 GHz and better than 10 dB up to 30 GHz.

  • A novel tunable multimodal bandpass filter

     Contreras Lizarraga, Adrian Arturo; Pradell Cara, Lluis; Ribó i Pal, Miquel
    European Microwave Week
    p. 1059-1062
    Presentation's date: 2011-10-11
    Presentation of work at congresses

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    This paper presents a novel uniplanar tunable bandpass filter. In this filter, each resonator can be reconfigured easily using PIN diodes or MEMS switches. Design equations are derived from a simple circuit model which takes into account the multimodal behavior of the coplanar waveguide. Experimental measurements of a 2-GHz prototype, featuring reconfigurable bandwidth and low losses, validate the filter topology and the proposed multimodal model.

  • Filtro uniplanar multimodal reconfigurable

     Contreras Lizarraga, Adrian Arturo; Ribó i Pal, Miquel; Pradell Cara, Lluis
    Simposium Nacional de la Unión Científica Internacional de Radio
    p. 1-4
    Presentation's date: 2011-09-08
    Presentation of work at congresses

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    A uniplanar filter based on two coplanar-waveguide odd-mode resonators is presented. The resonator feeding point is easily reconfigured using PIN diodes. As a result, the filter features reconfigurable bandwidth. A multimodal circuit model which takes into account the interaction between the two coplanar waveguide fundamental modes (even and odd) is derived and used to design a 2-GHz prototype. The experimental results show two relative-bandwidth states (14% and 21%) and low loss (1.1 dB), thus validating the filter concept and multimodal analysis.

  • U-Band micromachined coaxial filter

     Jaimes Vera, Edith Aline; Llamas Garro, Ignacio; Ke, Maolong; Wang, Yi; Lancaster, Michael J.; Pradell Cara, Lluis
    IEEE International Microwave Workshop Series on Millimeter Wave Integration Technologies
    p. 184-187
    DOI: 10.1109/IMWS3.2011.6061871
    Presentation's date: 2011-09-16
    Presentation of work at congresses

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    This paper presents a micromachined filter for millimeter-wave applications operating at U-band. The structure was designed using a rectangular coaxial line with the center conductor suspended in air. The rectangular coaxial cables have been optimized to provide a low attenuation constant. The design includes a coplanar waveguide (CPW)-to-coaxial transition to interface the device with other components, or coplanar probes for measurements. The filter has been designed with a center frequency of 42 GHz and a 10% fractional bandwidth. A measured insertion loss of 0.77 dB has been obtained. This structure involves a low-cost micromachining manufacturing process using SU-8 photo resist which is very attractive for the implementation of integrated millimeter wave subsystems.

  • A highly-repeatable, broadband 180º phase switch for integrated MEMS processes

     Llamas, Marco Antonio; Girbau, David; Ribó i Pal, Miquel; Pradell Cara, Lluis; Giacomozzi, Flavio; Colpo, Sabrina; Coccetti, Favio; Aouba, StephaneaOUBA
    International Symposium on RF MEMS and RF Microsystems
    Presentation's date: 2011-06-28
    Presentation of work at congresses

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    A broadband 0º/180º phase switch based on a slotline-coplanar-waveguide cross loaded with two MEMS switches in opposed (ON/OFF or OFF/ON) states, is reported. The fabrication was made on high-resistivity silicon substrates using the FBK-irst and LAAS-CNRS surface micromachining processes, showing a high repeatability. The measured phase shift is 180º +0º/-7º in the extremely wide frequency range 1–30 GHz.

  • Diseño de tecnologias integradas reconfigurables en banda milimétrica

     Barlabe Dalmau, Antoni; Casals Terre, Jasmina; Contreras Lizarraga, Adrian Arturo; Pradell Cara, Lluis
    Competitive project

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  • Yago Subsistemas reconfigurables

     Pradell Cara, Lluis
    Competitive project

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    Modelado circuital multimodal de un resonador pasobanda reconfigurable  Open access

     Contreras Lizarraga, Adrian Arturo; Ribó i Pal, Miquel; Pradell Cara, Lluis
    Simposium Nacional de la Unión Científica Internacional de Radio
    p. 1-3
    Presentation's date: 2010-09-15
    Presentation of work at congresses

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    In this work, we present a simple uniplanar bandpass resonator that can be used for the development of reconfigurable uniplanar filters. The multimodal behaviour of the coplanar waveguide is taken into account for the design of the resonator. We show that a simple multimodal model can be used to represent the proposed structure. Experimental measurements validate the accuracy of the proposed model.

  • Dispositivos coaxiales micromecanizados para banda milimétrica

     Jaimes Vera, Edith Aline; Pradell Cara, Lluis; Llamas Garro, Ignacio; Maolong, Ke; Wang, Yi; Lancaster, Michael J.
    Simposium Nacional de la Unión Científica Internacional de Radio
    p. 1-4
    Presentation's date: 2010-09-15
    Presentation of work at congresses

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  • RF-MEMS uniplanar 180º Phase Switch based on switching between two out-of-phase paths

     Llamas Morote, Marco Antonio; Ribó i Pal, Miquel; Girbau Sala, David; Pradell Cara, Lluis; Lázaro Guillén, Antonio; Giacomozzi, Flavio; Margesin, Benno
    International Conference on RF MEMS and RF Microsystems
    p. 1-4
    Presentation's date: 2010-06-28
    Presentation of work at congresses

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    A phase switch based on switching between two twoport passive networks with a phase difference of 180º is reported. Two RF MEMS single-pole-double-throw structures are used to select the phase path. The fabrication is made on both highresistivity silicon and quartz substrates using the eight-mask FBK-irst surface micromachining process. The measured phase shift is 180º±5º in the frequency range 14−20 GHz on quartz wafers and in the range 8−20 Ghz on silicon wafers.

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    DARFM - Introduction to narrow-band matching networks  Open access

     Torres Torres, Francisco; Pradell Cara, Lluis; Miranda, Jorge
    Date: 2010-03-01
    Report

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  • DARFM - Impedance, transformers and tapers  Open access

     Torres Torres, Francisco; Pradell Cara, Lluis
    Date: 2010-03-01
    Report

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  • Diplexor reconfigurable para estándares de transmisión y recepción WiFi-UMTS

     Brito Brito, Zabdiel; Llamas Garro, Ignacio; Navarro Muñoz, Guillem; Perruisseau Carrier, Julien; Pradell Cara, Lluis
    Simposium Nacional de la Unión Científica Internacional de Radio
    Presentation's date: 2010
    Presentation of work at congresses

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    In this paper a reconfigurable diplexer for WiFi and UMTS transmit and receive bands is presented. The diplexer has four possible frequency and bandwidth states, and consists of two reconfigurable filters connected by an SPDT switch. Simulated and measured results show a very good agreement. The diplexer specifications were successfully matched with the proposed topology.

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    Tunable dual-band filters based on capacitive-loaded stepped-impedance resonators  Open access

     Girbau, David; Lázaro, Antoni; Pérez, A.; Martínez, Ester; Pradell Cara, Lluis; Villarino, Ramon
    European Microwave Week
    p. 113-116
    Presentation's date: 2009-10-01
    Presentation of work at congresses

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    This paper proposes the design of tunable dual-band filters for multi-band multi-standard systems. The main objective is to provide frequency tunability in the second band while maintaining the first band fixed. To this end, the capacitive-loaded stepped-impedance resonator is used. The work is divided into two main parts. In the first part, a deep analysis of the capacitive-loaded stepped-impedance resonator structure is done, which provides analytical closed-form design equations which eases their design in front of the several approaches available in the literature up to now. The analysis is also particularized for the case of the capacitive-loaded uniform resonator. In the second part, resonators are integrated in two dual-band tunable filters.

  • Filtros sintonizables de banda dual basados en resonadores de salto de impedancia cargados capacitivamente

     Girbau, David; Lázaro, Antoni; Pérez, Albert; Martínez, Ester; Pradell Cara, Lluis; Villarino Villarino, Ramon
    Simposium Nacional de la Unión Científica Internacional de Radio
    Presentation's date: 2009-09-17
    Presentation of work at congresses

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  • Filtros para un cabezal de comunicaciones entre vehículos

     Brito Brito, Zabdiel; Llamas Garro, Ignacio; Navarro Muñoz, Guillem; Perruisseau Carrier, Julien; Pradell Cara, Lluis
    Simposium Nacional de la Unión Científica Internacional de Radio
    Presentation's date: 2009-09-16
    Presentation of work at congresses

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  • Circuitos de microondas uniplanares multimodales, reconfigurables

     Llamas Morote, Marco Antonio
    Department of Signal Theory and Communications, Universitat Politècnica de Catalunya
    Theses

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    Characterization of dynamics in RF-MEMS switches  Open access

     Llamas, Marc; Girbau, David; Pradell Cara, Lluis; Lázaro, Antoni; Giacomozzi, Flavio; Colpo, Sabrina
    International Conference on RF MEMS and RF Microsystems
    p. 2627-2633
    DOI: 10.1109/TMTT.2004.837198
    Presentation's date: 2009-07-06
    Presentation of work at congresses

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    This paper proposes a new method to measure dynamics and power handling of RF microelectromechanical systems (MEMS) devices based on a mobile membrane. The method uses in-phase/quadrature demodulation of an RF signal proportional to the reflection coefficient of the measured device, which contains information of its mechanical properties, such as actuation and release times and instantaneous position of the mobile membrane. Both one-port (capacitors) and two-port devices (switches and extended tuning-range capacitors) can be measured. Its main advantage is the capability of obtaining information from both magnitude and phase variations of the device reflection coefficient to characterize its dynamics and power handling. It is shown that detecting phase is advantageous in high quality factor capacitors, where the magnitude of the reflection coefficient is nearly constant for any position of the mobile membrane. Open-short-load calibration of the system is provided in order to obtain absolute measurements, which are necessary for power-handling characterization. The performances of the proposed method are demonstrated by comparison to systems based on detection of the magnitude of the reflection coefficient. A MEMS capacitor is characterized in terms of dynamics—actuation and release times, and mechanical resonance frequency—and in terms of power handling—membrane instantaneous position and phase and tuning range variation.

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    Characterizing a Tune-all bandstop filter  Open access

     Musoll, Carles; Llamas Garro, Ignacio; Brito Brito, Zabdiel; Pradell Cara, Lluis; Corona, Alfonso
    IEEE MTT-S Int. Microwave Workshop Series on Signal Integrity and High-Speed Interconnects
    p. 55-58
    DOI: 10.1109/IMWS.2009.4814908
    Presentation's date: 2009-02-19
    Presentation of work at congresses

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    In this paper a reconfigurable bandstop filter able to reconfigure central frequency, bandwidth and selectivity for fine tuning applications is presented. The reconfigurable filter topology has four poles and a quasielliptic bandstop filter response. The filter is tuned by varactor diodes placed at different locations on the filter topology. The varactors are voltage controlled in pairs due to filter symmetry for central frequency and bandwidth control. An additional varactor is placed on a crossing line to move a pair of transmission zeros, closer or farther to the filter central frequency, which tunes filter selectivity. The filter has a tuneable fractional bandwidth range from 11.51 to 15.46%, a tuneable central frequency range from 1.346 to 1.420 GHz and a selectivity tuning range from 0.37 to 0.40 dB/MHz.

  • Access to the full text
    Capacitive and resistive RF-MEMS switches 2.5D & 3D electromagnetic and circuit modelling  Open access

     Llamas, Marc; Girbau, David; Pausas, Esther; Pradell Cara, Lluis; Aouba, StephaneaOUBA; Villneuve, C; Puyal, Vincent; Pons, Patrick; Plana, Robert; Giacomozzi, Flavio; Colpo, Sabrina
    Spanish Conference on Electron Devices
    p. 451-454
    DOI: 10.1109/SCED.2009.4800531
    Presentation's date: 2009-02-11
    Presentation of work at congresses

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    this paper proposes different strategies for the electrical modelling of capacitive and resistive RF-MEMS switches which take into account the dependence of the electrical performance on the mechanical properties and technological processes. The EM modelling of MEMS switches is addressed with 2.5D and 3D full wave EM softwares. More specifically, ADS-MomentumTM (2.5D) and EMDSTM (3D) from Agilent Technologies are used. Capacitive RF-MEMS switches were fabricated with the LAAS-CNRS 6-mask RF-MEMS process in Toulouse, France, and resistive RF-MEMS switches were fabricated with the FBK-irst 8-mask RF-MEMS process in Trento, Italy. It is shown that, by applying the proposed strategies, 2.5D and 3D simulations are in good agreement with characterization results.

  • UMTS-WiFi switchable bandpass filter

     Brito Brito, Zabdiel; Llamas Garro, Ignacio; Navarro Muñoz, Guillem; Perruisseau Carrier, Julien; Pradell Cara, Lluis
    European Microwave Week
    p. 125-128
    Presentation's date: 2009
    Presentation of work at congresses

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    In this paper a reconfigurable bandpass filter able to switch between WiFi and UMTS transmit band standards is presented. The filter is designed in such a way that center frequency and bandwidth specifications are precisely met by defining a switchable filter topology that includes two folded resonator extensions switched by two PIN diodes. Design specifications require two center frequency states, one at 2.440 GHz with an 80 MHz bandwidth and a second center frequency state at 1.955 GHz with a 140 MHz bandwidth for the WiFi and UMTS transmit bands, respectively. Filter simulations were performed to match the required filter specifications. Measured results on the filter show a very good agreement with the simulations where a 2.428 GHz center frequency with a 71 MHz bandwidth was obtained for the WiFi state, and a 1.939 GHz center frequency with a 144 MHz bandwidth was obtained for the UMTS filter state. The simulated filter insertion losses were -3.339 and -3.796 dB for the WiFi and UMTS states, respectively. Measured insertion losses were -3.345 and -3.837 dB for the WiFi and UMTS states, respectively. The filter specifications were successfully matched with the proposed filter topology, where simulated and measured responses are in good agreement.

  • Design and Optimization of RF Power LDMOS Transistors for Base Station Applications

     CORTES MAYOL, IGNACIO
    Department of Electronic Engineering, Universitat Politècnica de Catalunya
    Theses

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  • Filtro Banda Eliminada con Reconfigurabilidad Continua en Selectividad, Ancho de Banda y Frecuencia Central

     Carles, Musoll; Llamas Garro, Ignacio; Zabdiel, Brito; Pradell Cara, Lluis; Alonso, Corona
    Simposium Nacional de la Unión Científica Internacional de Radio
    Presentation of work at congresses

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  • A Single-Pole-Double-Throw Switch Based on Capacitive-Anchored MEMS

     Girbau, David; Marco Llanas, Antonio; Antonio, Lázaro; Pradell Cara, Lluis; Jaume, Prada; Pierre, Calmon; Patrick, Pons; Robert, Plana
    9th International Conference on RF MEMS and RF Microsystems - MEMSWAVE-2008
    Presentation of work at congresses

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  • Diseño de dispositivos micro-conmutadores RF-MEMS capacitivos con metalizacion flotante

     Marco Llanas, Antonio; Girbau, David; Esther, Pausas; Pradell Cara, Lluis; Giacomozzi, Flavio; Carlos, Calaza
    Simposium Nacional de la Unión Científica Internacional de Radio
    Presentation of work at congresses

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  • Microstrip Switchable Bandstop Filter using PIN Diodes with Precise Frequency and Bandwidth Control

     Brito Brito, Zabdiel; Llamas Garro, Ignacio; Pradell Cara, Lluis; Alonso, Corona
    European Microwave Conference 2008
    Presentation of work at congresses

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  • Nuevas arquitecturas para circuitos de comunicaciones de microondas, basadas en MEMS de RF

     Casals Terre, Jasmina; Pradell Cara, Lluis; Barlabe Dalmau, Antoni
    Competitive project

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  • Informe RUN1 LAAS

     Llamas, M A; Girbau, D; Pradell Cara, Lluis
    Date: 2007-07
    Report

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  • Informe RUN2 Alumina

     Llamas, M A; Girbau, D; Pradell Cara, Lluis
    Date: 2007-04
    Report

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  • Diccionari de Telecomunicacions

     Aguilar Igartua, Mónica; Alcober Segura, Jesus Angel; Altes Bosch, Jorge; Aragones Cervera, Xavier; Artigas Garcia, David; Bardes Llorensi, Daniel; Barlabe Dalmau, Antoni; Bragos Bardia, Ramon; Calderer Cardona, Josep; Cardama Aznar, Angel; Casademont Serra, Jordi; Casals Ibañez, Lluis; Comeron Tejero, Adolfo; Cotrina Navau, Josep; Cruz Llopis, Luis Javier de La; Dios Otin, Victor Federico; Duxans Barrobes, Helena; Esparza Martin, Oscar; Esquerra Llucià, Ignasi; Garcia Vizcaino, David; Garcies Salva, Pau; Gomez Montenegro, Carlos; Gorricho Moreno, Juan Luis; Guinjoan Gispert, Francisco; Hesselbach Serra, Xavier; Liria Righetti, Antoni; Lopez Salcedo, Jose Antonio; Madrenas Boadas, Jordi; Madueño Ruiz, María Isabel; Mestre Pons, Francesc Xavier; Monte Moreno, Enrique; Morros Rubió, Josep Ramon; Muñoz Tapia, Jose Luis; Pallares Segarra, Esteve; Pons Nin, Joan; Recolons Martos, Jaume; Rincon Rivera, David; Riu Costa, Pere Joan; Ruiz Vela, Inmaculada; Pradell Cara, Lluis; Pascual Iserte, Antonio; Prat Viñas, Luis; Rey Micolau, Francesc; Villares Piera, N. Javier
    Date of publication: 2007-03
    Book

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  • Metode_mesura_dutNports_VNA2ports

     Llamas, M A; Girbau, D; Pradell Cara, Lluis
    Date: 2007-02
    Report

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  • Electrothermally-actuated RF-MEMS devices manufactured on a low-resistivity substrate

     Girbau, David; Pradell Cara, Lluis; Llamas, M A; Antonio, Lázaro; Àlvar, Nebot
    8th International Conference on RF MEMS and RF Microsystems
    p. 227-230
    Presentation of work at congresses

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  • Dispositivos MEMS de RF con actuación electrotérmica fabricados en substrato de de baja resistividad

     Girbau, D; Pradell Cara, Lluis; Llamas, M A; Lázaro, A
    Simposium Nacional de la Unión Científica Internacional de Radio
    Presentation of work at congresses

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  • VTT design report RUN1

     Llamas, M A; Pradell Cara, Lluis
    Date: 2007-01
    Report

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  • Itc IRST design report RUN1

     Llamas, M A; Pradell Cara, Lluis
    Date: 2007-01
    Report

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  • Non linear actuation model for lateral electrostatically-actuated DC-contact RF MEMS series switches

     Lazaro, A; Girbau, D; Pradell Cara, Lluis; Nebot Castells, Maria Angela
    Spanish Conference on Electron Devices
    p. 181-184
    Presentation of work at congresses

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  • Compact, Wideband CPW-to-Slotline Multimodal Transition

     Llamas, M A; Girbau, David; Miquel, Ribó; Pradell Cara, Lluis
    European Microwave Conference
    Presentation of work at congresses

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  • Transición multimodal CPW-slotline compacta, de banda ancha

     Llamas, M A; Girbau, D; Ribó i Pal, Miquel; Pradell Cara, Lluis
    Simposium Nacional de la Unión Científica Internacional de Radio
    Presentation of work at congresses

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