Now showing items 1-20 of 254

    • 100 GHz retina for THz tomographic imaging 

      Alonso, Maria; Guerra, C.; Nova, Enrique; Abril, Jordi; Romeu Robert, Jordi; Llombart, Nuria; Jofre Roca, Lluís (2011)
      Conference report
      Restricted access - publisher's policy
      In a tomographic imaging system, the key is to collect a sufficient number of scattered field points to recover the currents in the inverse scattering problem. This can be accomplished by using a real array of multiplexed ...
    • 3-D printed UWB microwave bodyscope for biomedical measurements 

      Rashid, Saba; Jofre Roca, Lluís; Garrido, Alejandra; González, Giselle; Ding, Yongsheng; Aguasca Solé, Alberto; O'Callaghan Castellà, Juan Manuel; Romeu Robert, Jordi (2019-02-15)
      Article
      Open Access
      In this letter, a three-dimensional (3-D) printed compact ultrawideband (UWB) extended gap ridge horn (EGRH) antenna designed to be used for biological measurements of the human body is described. The operational frequency ...
    • 3D arrayed microwave tomographic system for medical imaging 

      Guardiola Garcia, Marta; Jofre Roca, Lluís; Gedda, F.; Capdevila Cascante, Santiago; Romeu Robert, Jordi; Blanch Boris, Sebastián (2010)
      Conference report
      Open Access
      In this paper, a combined tomographic imaging system comprising the rotation of a multiplexed linear antenna array around the object under test is designed. With this system a cylindrical sampling is obtained, allowing to ...
    • 3D UWB magnitude-combined tomographic imaging for biomedical applications. Algorithm validation 

      Guardiola Garcia, Marta; Jofre Roca, Lluís; Capdevila Cascante, Santiago; Blanch Boris, Sebastián; Romeu Robert, Jordi (2011-06)
      Article
      Open Access
      Biomedical microwave imaging is a topic of continuous research for its potential in different areas especially in breast cancer detection. In this paper, 3D UWB Magnitude-Combined tomographic algorithm is assessed for ...
    • 3D UWB tomography for medical imaging applications 

      Guardiola Garcia, Marta; Jofre Roca, Lluís; Romeu Robert, Jordi (2010)
      Conference report
      Open Access
      In this paper, a novel 3D UWB tomographic algorithm has been presented for brain hemorrhagic stroke detection. While 2D reconstructions are unable to distinguish between features at different heights, 3D reconstructions ...
    • 3D-printed UHF-RFID tag for embedded applications 

      Vidal, Neus; Lopez-Villegas, Josep Maria; Romeu Robert, Jordi; Salas Barenys, Arnau; Garcia-Miquel, Aleix; González López, Giselle; Jofre Roca, Lluís (Institute of Electrical and Electronics Engineers (IEEE), 2020-08-10)
      Article
      Open Access
      This paper presents the design, manufacture and characterization of a novel 3D passive UHF-RFID tag for embedded applications. The prototype is fabricated using additive manufacturing techniques: 3D printing and copper ...
    • 60GHz channel characterization using a Scatterer Mapping Technique 

      Papió, Anna; Grau, Alfred; Balcells Ventura, Jordi; Romeu Robert, Jordi; Jofre Roca, Lluís; Flaviis, Franco de (2010)
      Conference report
      Open Access
      In this paper, a Scatterer Mapping Technique based on a Multi-Frequency Bi-focusing operator with good imaging capabilities is used to characterize the 60GHz wireless channel in an office environment. The measurement data ...
    • A 3D printed lens antenna for 5G applications 

      Ballesteros, Christian; Maestre, Marcos; Santos Blanco, M. Concepción; Romeu Robert, Jordi; Jofre Roca, Lluís (Institute of Electrical and Electronics Engineers (IEEE), 2019)
      Conference lecture
      Open Access
      A switchable multi-antenna architecture for lens-assisted beamsteering in the Ka-band region allocated for 5G communications (24-30 GHz) is proposed. The radiating elements are bow-tie antennas mounted with a 3D printed ...
    • A contact-less small antenna characterization through impedance modulation 

      Monsalve Carcelen, Beatriz; Blanch Boris, Sebastián; Romeu Robert, Jordi; Jofre Roca, Lluís (IEEE Press. Institute of Electrical and Electronics Engineers, 2009)
      Conference report
      Open Access
      In smalls antennas S-parameters measurements are highly influenced by the measurement equipment as well as the environment. In order to avoid this inconvenience, a wireless and non-invasive characterization setup is required. ...
    • A cylindrical array for fast microwave tomography 

      de los Reyes, Elías; Jofre Roca, Lluís; Broquetas Ibars, Antoni; Elias Fusté, Antoni; Cardama Aznar, Ángel (Unión Científica Internacional de Radio (URSI), 1987)
      Conference report
      Open Access
    • A cylindrical system for quasy-real time microwave tomography 

      Jofre Roca, Lluís; Reyes, E De Los; Ferrando Bataller, Miquel; Elias Fusté, Antoni; Romeu Robert, Jordi; Baquero, M; Rius Casals, Juan Manuel (Institute of Electrical and Electronics Engineers (IEEE), 1986)
      Conference report
      Open Access
      A cylindrical system for biomedical microwave tomography is presented. The circular algorithms and some numerical reconstructions are discussed. Finally the experimental set-up is described and some preliminary measurements ...
    • A dynamic load balancing method for the evaluation of chemical reaction rates in parallel combustion simulations 

      Muela Castro, Jordi; Borrell Pol, Ricard; Ventosa Molina, Jordi; Jofre Roca, Lluís; Lehmkuhl Barba, Oriol; Pérez Segarra, Carlos David (Elsevier, 2019-08-15)
      Article
      Open Access
      The development and assessment of an efficient parallelization method for the evaluation of reaction rates in combustion simulations is presented. Combustion simulations where the finite-rate chemistry model is employed ...
    • A figure of merit to assess the performance of photoconductive antennas at terahertz band 

      Romeu Robert, Jordi; Cea Falcó, Marc de; Jofre Roca, Lluís; Yazgan, Ahmet Utku (Institute of Electrical and Electronics Engineers (IEEE), 2017)
      Conference report
      Restricted access - publisher's policy
      Photoconductive antennas are one of the most efficient ways to radiate and receive EM waves around the 1 THz frequency band. The physical processes involved in photoconductive terahertz signal generation are complex enough ...
    • A figure-of-merit for pattern reconfigurable antennas 

      Rodrigo López, Daniel; Romeu Robert, Jordi; Capdevila Cascante, Santiago; Jofre Roca, Lluís (2013-03)
      Article
      Restricted access - publisher's policy
      The performance of pattern reconfigurable antennas is evaluated with the purpose of deriving a figure-of-merit for pattern reconfigurability. A general formulation is provided for the average gain achieved by a ...
    • A frequency reconfigurable cell for beam-scanning reflectarrays 

      Rodrigo López, Daniel; Jofre Roca, Lluís; Perruisseau Carrier, Julien (Institute of Electrical and Electronics Engineers (IEEE), 2013)
      Conference report
      Restricted access - publisher's policy
      Reflectarray antennas are excellent candidates for beam-scanning applications thanks to their low loss, light and quasi-planar structure and ease of electronic control. However, reflectarray antennas suffer from narrower ...
    • A near field spherical wave inverse synthetic aperture radar technique 

      Broquetas Ibars, Antoni; Jofre Roca, Lluís; Cardama Aznar, Ángel (Institute of Electrical and Electronics Engineers (IEEE), 1992)
      Conference report
      Open Access
      The authors present an imaging near-field spherical wave inverse synthetic aperture radar (SWISAR) algorithm based on a focusing operator of the scattered fields on the target surface. A spherical wave can be easily generated ...
    • A new class of antenna array with a reconfigurable element factor 

      Li, Zhouyuan; Rodrigo López, Daniel; Jofre Roca, Lluís; Cetiner, Bedri Artug (2013-04)
      Article
      Restricted access - publisher's policy
      A parasitic layer-based multifunctional reconfigurable antenna array (MRAA) formed by the linear combination of four (4 1) identical multifunctional reconfigurable antenna (MRA) elements is presented. Each MRA produces ...
    • A novel compact UHF wideband antenna for near field electrical characterization of Steel Fiber Reinforced Concrete 

      Roqueta Crusats, Gemma; Irteza, I; Romeu Robert, Jordi; Jofre Roca, Lluís (IEEE Computer Society Publications, 2009)
      Conference report
      Open Access
      A novel, electrically small, UHF (350 MHz–750 MHz)microstrip slot antenna is presented. The antenna is designed for the characterization of Steel Fiber Reinforced Concrete (SFRC) segments. The antenna consists on a three ...
    • A quad-band antenna for public safety applications 

      Mopidevi, Hema Swaroop; Damgaci, T; Rodrigo López, Daniel; Jofre Roca, Lluís; Cetiner, Bedri Artug (2014-01-01)
      Article
      Restricted access - publisher's policy
      The design, fabrication, and characterization of a frequency-reconfigurable antenna for the United States Public Safety (PS) wireless communication applications are presented. This antenna is quad-band operating in the PS ...
    • A reconfigurable antenna with beam steering and beamwidth variability for wireless communications 

      Towfiq, Asaduzzaman; Bahceci, Israfil; Blanch Boris, Sebastián; Romeu Robert, Jordi; Jofre Roca, Lluís; Cetiner, Bedri Artug (2018-07-12)
      Article
      Open Access
      A reconfigurable antenna (RA) capable of steering its beam into the hemisphere corresponding to ¿ ¿ {-40°,0°,40°}, Ø ¿ {0°,45°,90°,-45°}, and of changing 3-dB beamwidth, where ¿3dB ¿ (40°,100°), Ø ¿ {45°,90°,-45°} for ...