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Ara es mostren els items 21-40 de 134

    • Asymptotic error exponents in energy-detector and estimator-correlator signal detection 

      Font Segura, Josep; Vázquez Grau, Gregorio; Riba Sagarra, Jaume (IEEE Computational Intelligence Society, 2012)
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      The performance in signal detection is evaluated by the error (false-alarm and missed-detection) probabilities. However, calculating these probabilities is a difficult task in practice. This paper studies the asymptotic ...

    • Automatic left ventricular contour extraction for volume calculation from echocardiographic images 

      Gasull Llampallas, Antoni; Torres Urgell, Lluís; Marqués Acosta, Fernando; Vázquez Grau, Gregorio (1989)
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      This paper presents a new fully automated algorithm that extracts LV epicardial and endocardial borders from 2-D echocardiograms. The method is based on a radial search approach, which is the best way to use some a priori ...

    • Bit-slice implementation of a linear predictive vocoder 

      Vázquez Grau, Gregorio; Gasull Llampallas, Antoni (1985)
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      A digital 16-bit high-speed general-purpose signal-processor is shown. The main objective has been the implementation of a linear predictive vocoder for obtaining real-time speech compression. For real-time digital speech ...

    • Blind equalization based on spatial and temporal diversity in block coded modulations 

      Rey Micolau, Francesc; Lamarca Orozco, M. Meritxell; Vázquez Grau, Gregorio (Institute of Electrical and Electronics Engineers (IEEE), 1998)
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      Linear block codes can be applied in spatial and/or temporal diversity receivers in order to develop high performance schemes for blind equalization in mobile communications. The proposed technique uses the structure of ...

    • Blind equalization of DS-CDMA and MC-CDMA modulations in time-variant frequency selective channels 

      Rey Micolau, Francesc; Vázquez Grau, Gregorio (Institute of Electrical and Electronics Engineers (IEEE), 1999)
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      The paper addresses the blind equalization problem of spread spectrum modulations in the presence of fast time-variant frequency-selective channels. The basic assumption of the paper is that the channel response exhibits ...

    • Channel estimation for transform modulations in mobile communications 

      Lamarca Orozco, M. Meritxell; Vázquez Grau, Gregorio (1996)
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      This paper deals with data-aided channel estimation in systems using OFDM modulation. We formulate a pilot symbol-based channel estimator and compare it with the pilot-tone one proposed in [1]. Although this paper focuses ...

    • Compressed correlation-matching for spectrum sensing in sparse wideband regimes 

      Font Segura, Josep; Vázquez Grau, Gregorio; Riba Sagarra, Jaume (IEEE Press. Institute of Electrical and Electronics Engineers, 2011)
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      In this paper, we consider a novel compressed correlation-matching (CCM) approach for spectrum sensing of wideband sparse signals. We derive a general closed-form estimate of the wideband sparse signal level from compressed ...

    • Conditional maximum likelihood frequency estimation for staggered modulations 

      Riba Sagarra, Jaume; Vázquez Grau, Gregorio (1998)
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      The use of spectrally efficient continuous phase modulations for mobile communications may lead to a serious performance degradation of the classical frequency error detectors (FEDs) due to the presence of self-noise. This ...

    • Conditional maximum likelihood timing recovery 

      Riba Sagarra, Jaume; Vázquez Grau, Gregorio (Institute of Electrical and Electronics Engineers (IEEE), 1999)
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      The conditional maximum likelihood (CML) principle, well known in the context of sensor array processing, is applied to the problem of timing recovery. A new self-noise free CML-based timing error detector is derived. ...

    • Conditional maximum likelihood timing recovery: estimators and bounds 

      Riba Sagarra, Jaume; Sala Álvarez, José; Vázquez Grau, Gregorio (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2001-04-30)
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      This paper is concerned with the derivation of new estimators and performance bounds for the problem of timing estimation of (linearly) digitally modulated signals. The conditional maximum likelihood (CML) method is adopted, ...

    • Constant variance transversal filtering for adaptive channel equalization 

      Vázquez Grau, Gregorio; Gasull Llampallas, Antoni; Sanchez, J J; Lagunas Hernandez, Miguel A. (1989)
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    • D1. Estudio de códigos PN para mejorar el ensanchado y la eficiencia espectral del sistema CDMA síncrono y asíncrono 

      Lamarca Orozco, M. Meritxell; Rey Micolau, Francesc; Riba Sagarra, Jaume; Sala Álvarez, José; Vázquez Grau, Gregorio; Villares Piera, Nemesio Javier (2008-11-10)
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    • D2. Estructuras de detector multiusuario para CDMA síncrono y asíncrono 

      Lamarca Orozco, M. Meritxell; Rey Micolau, Francesc; Riba Sagarra, Jaume; Sala Álvarez, José; Vázquez Grau, Gregorio; Villares Piera, Nemesio Javier (2008-11-10)
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    • D3. Sincronización robusta de frecuencia y fase para M-PSK sobre CDMA 

      Lamarca Orozco, M. Meritxell; Rey Micolau, Francesc; Riba Sagarra, Jaume; Sala Álvarez, José; Vázquez Grau, Gregorio; Villares Piera, Nemesio Javier (2008-11-10)
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    • DA-GLRT burst detection and synchronization based on a chirp-like preamble 

      Rodríguez, E; Lamarca Orozco, M. Meritxell; López Salcedo, José Antonio; Rey Micolau, Francesc; Riba Sagarra, Jaume; Sala Álvarez, José; Vázquez Grau, Gregorio; Villares Piera, Nemesio Javier; Jalón, A (2008)
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      A specific preamble for the tasks of signal detection and synchronization in burst digital communications is presented. The preamble resembles a chirp signal used in RADAR applications. Its main benefit is that it allows ...

    • Data pre-processing for high-resolution adaptive algorithms 

      Vázquez Grau, Gregorio; Gasull Llampallas, Antoni (Institute of Electrical and Electronics Engineers (IEEE), 1988)
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      The inclusion of adaptive methods in high-resolution spectral estimation algorithms is considered. The generation of a complete family of spectral estimators from the normalized maximum-likelihood method (MLM) is discussed. ...

    • Data pre-processing for high-resolution adaptive algorithms 

      Vázquez Grau, Gregorio; Gasull Llampallas, Antoni (Institute of Electrical and Electronics Engineers (IEEE), 1988)
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      The inclusion of adaptive methods in high-resolution spectral estimation algorithms is considered. The generation of a complete family of spectral estimators from the normalized maximum-likelihood method (MLM) is discussed. ...

    • Data-dependent error weighting for constant variance transversal filtering 

      Vázquez Grau, Gregorio (Elsevier, 1990)
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    • Decentralized shaping for pilot generation and detection in opportunistic communications 

      Borràs Pino, Jordi; Vázquez Grau, Gregorio (Institute of Electrical and Electronics Engineers (IEEE), 2019)
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      The uncoordinated design of pulse shaping filters for opportunistic communications is addressed. We show that under degrees-of-freedom sensing uncertainties the waveform design problem can be cast as a minimum-norm ...

    • Descripciones tiempo-frecuencia en la recuperacion conjunta de param 

      Riba Sagarra, Jaume; Vázquez Grau, Gregorio (Universidad de Málaga, 1992)
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