Now showing items 241-260 of 355

    New generation FTTH ONU and OLT design for upstream transmission in WDM PON including optimized combination of electronics and optics 

    Omella Cancer, Mireia (Date of defense: 2010-10-18)

    This research is developed in the context of the Next Generation of Passive Optical Networks (NG-PON) for Fibre to the Home (FTTH) network. In this thesis, several techniques are proposed in order to increase the network ...

    Part-based object retrieval with binary partition trees 

    Giró i Nieto, Xavier (Date of defense: 2012-05-31)

    This thesis addresses the problem of visual object retrieval, where a user formulates a query to an image database by providing one or multiple examples of an object of interest. The presented techniques aim both at finding ...

    Surface reconstruction for multi-view video 

    Salvador Marcos, Jordi (Date of defense: 2011-09-23)

    This thesis introduces a methodology for obtaining an alternative representation of video sequences captured by calibrated multi-camera systems in controlled environments with known scene background. This representation ...

    Voice source characterization for prosodic and spectral manipulation 

    Pérez Mayos, Javier (Date of defense: 2012-07-03)

    The objective of this dissertation is to study and develop techniques to decompose the speech signal into its two main components: voice source and vocal tract. Our main efforts are on the glottal pulse analysis and ...

    Network coding-aided MAC protocols for cooperative wireless networks 

    Antonopoulos, Angelos (Date of defense: 2012-12-17)

    The introduction of third generation (3G) technologies has caused a vast proliferation of wireless devices and networks, generating an increasing demand for high level Quality of Service (QoS). The wide spread of mobile ...

    Síntesis de voz aplicada a la traducción voz a voz 

    Agüero, Pablo Daniel (Date of defense: 2012-10-23)

    In the field of speech technologies, text-to-speech conversion is the automatic generation of artificial voices that sound identical to a human voice when reading a text in loud speech. Inside a text-to-speech system, the ...

    Advanced routing mechanisms in ASON/GMPLS networks 

    Agraz Bujan, Fernando (Date of defense: 2012-10-01)

    Current network infrastructures are supported on a layered model whereby heterogeneous data traffic can be seamlessly transported. In this architecture, where client/server relationships are established between adjacent ...

    Ocean monitoring using L-Band microwave radiometry and GNSS-R 

    Valencia Domènech, Enric (Date of defense: 2012-10-17)

    The knowledge of sea surface salinity (SSS) is a key issue to understand and monitor the Earth¿s water cycle. Accurate and systematic measurement of SSS was not possible until the ESA¿s Soil Moisture and Ocean Salinity ...

    Contribution to the characterization of interferometric radiometers devoted to Earth observation: application to the MIRAS/SMOS payload 

    González Gambau, Verónica (Date of defense: 2012-09-05)

    The variability of soil moisture and ocean salinity controls the continuous exchange of water between the oceans, the atmosphere and the land. Therefore, the accurate and periodic measurements of these geophysical variables ...

    Phase synchronization scheme for very long baseline coherent arrays 

    Merlano Duncan, Juan Carlos (Date of defense: 2012-07-26)

    Precise phase synchronization of clock or local oscillator signals over distributed systems is a recurring requirement in the design of a wide range of systems, with applications in telecommunications and, for example, in ...

    Resource Management in Multicarrier Based Cognitive Radio Systems 

    Shaat, Musbah M. R. (Date of defense: 2012-03-09)

    The ever-increasing growth of the wireless application and services affirms the importance of the effective usage of the limited radio spectrum. Existing spectrum management policies have led to significant spectrum ...

    Cross-layer design and optimization of medium access control protocols for wlans 

    Kartsakli, Elli (Date of defense: 2012-02-16)

    This thesis provides a contribution to the field of Medium Access Control (MAC) layer protocol design for wireless networks by proposing and evaluating mechanisms that enhance different aspects of the network performance. ...

    Pau-synthetic aperture: a new instrument to test potential improvements for future interferometric radiometers 

    Ramos Pérez, Isaac (Date of defense: 2012-02-27)

    The Soil Moisture and Ocean Salinity (SMOS) mission is an Earth Explorer Opportunity mission from the European Space Agency (ESA). It was a direct response to the global observations of soil moisture and ocean salinity. ...

    Computing resource management in software-defined and cognitive radios 

    Marojevic, Vuk (Date of defense: 2010-10-09)

    Our research aims at contributing to the evolution of modern wireless communications and to the development of software-defined radio (SDR) and cognitive radio, in particular. It promotes a general resource management ...

    Multiscale soil moisture retrievals from microwave remote sensing observations 

    Piles Guillem, Maria (Date of defense: 2010-07-16)

    La humedad del suelo es la variable que regula los intercambios de agua, energía, y carbono entre la tierra y la atmósfera. Mediciones precisas de humedad son necesarias para una gestión sostenible de los recursos hídricos, ...

    Contribution to radio resource and spectrum management strategies in wireless access networks: a markov modeling approach 

    Gelabert Doran, Xavier (Date of defense: 2010-07-12)

    Las redes inal´ambricas actuales exhiben caracter´ısticas heterog´eneas de acceso m´ultiple mediante el despliegue, la coexistencia y la cooperaci´on de varias Tecnolog ´ıas de Acceso Radio (RAT2). En este escenario, la ...

    Detection and handling of overlapping speech for speaker diarization 

    Zelenák, Martin (Date of defense: 2012-01-31)

    For the last several years, speaker diarization has been attracting substantial research attention as one of the spoken language technologies applied for the improvement, or enrichment, of recording transcriptions. ...

    Contributions to earth observation using gnss-r opportunity signals 

    Rodriguez Alvarez, Nereida (Date of defense: 2011-12-22)

    During years a number of satellites have been developed to remotely sense Earth geophysical parameters for weather forecasting and other climate studies. In recent years the use of reflected Global Navigation Satellite ...

    Contribution to resource management in cellular access networks with limited backhaul capacity 

    Galeana Zapién, Hiram (Date of defense: 2011-02-25)

    La interfaz radio de los sistemas de comunicaciones móviles es normalmente considerada como la única limitación de capacidad en la red de acceso radio. Sin embargo, a medida que se van desplegando nuevas y más eficientes ...

    Contributrion to the improvement of the soil moisture and ocean salinity (SMOS) sea surface salinity retrieval algorithm 

    Talone, Marco (Date of defense: 2010-11-22)

    The European Space Agency's Soil Moisture and Ocean Salinity (SMOS) satellite was launched on November, 2, 2009 from the Russian cosmodrome of Plesetsk. Its objective is to globally and regularly collect measurements ...