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    • ENN: a neural network with DCT adaptive activation functions 

      Martínez Gost, Marc; Pérez Neira, Ana Isabel; Lagunas Hernandez, Miguel A. (Institute of Electrical and Electronics Engineers (IEEE), 2024-02-01)
      Article
      Accés obert
      The expressiveness of neural networks highly depends on the nature of the activation function, although these are usually assumed predefined and fixed during the training stage. Under a signal processing perspective, in ...

    • Error rate analysis and optimal power allocation in multiple access relay channels with analog network coding 

      Ntontin, Konstantinos; Di Renzo, Marco; Pérez Neira, Ana Isabel; Verikoukis, Christos (Institute of Electrical and Electronics Engineers (IEEE), 2014)
      Text en actes de congrés
      Accés restringit per política de l'editorial
      In this paper, we examine multi-source multi-relay systems that employ Analog Network Coding for which we provide a two-fold contribution: i) We derive a closed-form upper bound of the average symbol error rate (SER) ...

    • Estimación recursiva simultánea de potencia y DOA por ajuste de la matriz de covarianza asociada a la apertura 

      Pérez Neira, Ana Isabel; Lagunas Hernandez, Miguel A. (1992)
      Text en actes de congrés
      Accés obert
      The small error approximation is used to derive a linear relationship between the source parameters (i.e. power levels and directions of arrival or DOA's) and a measurement of the covariance error matrix, defined as the ...

    • Evaluation of spectrum opportunities in the GSM band 

      Carniani, Andrea; Giupponi, Lorenza; Verdone, Roberto; Pérez Neira, Ana Isabel (2009)
      Text en actes de congrés
      Accés obert
      In this paper we explore the possibility of exploiting underutilized channels in the GSM bands. The secondary (unlicensed) users of the spectrum are the nodes of an overlay cognitive ad-hoc network, which opportunistically ...

    • Evolution of spatial and multicarrier scheduling: towards multi-cell scenario 

      Henarejos Hernández, Pol; Pérez Neira, Ana Isabel; Tralli, Velio; Moretti, Marco; Dimitriou, Nikos; Dainelli, Giulio (2010)
      Text en actes de congrés
      Accés obert
      OFDMA systems are considered as the promising multiple access scheme of next generation multi-cellular wireless systems. In order to ensure the optimum usage of radio resources, OFDMA radio resource management algorithms ...

    • Examen Final 

      Pérez Neira, Ana Isabel (Universitat Politècnica de Catalunya, 2019-01-08)
      Examen
      Accés restringit a la comunitat UPC

    • Examen Final 

      Pascual Iserte, Antonio; Pérez Neira, Ana Isabel; Riba Sagarra, Jaume (Universitat Politècnica de Catalunya, 2021-06-17)
      Examen
      Accés restringit a la comunitat UPC

    • Examen Final 

      Pérez Neira, Ana Isabel (Universitat Politècnica de Catalunya, 2014-06-06)
      Examen
      Accés restringit a la comunitat UPC

    • Examen Final 

      Cabrera-Bean, Margarita; Pascual Iserte, Antonio; Pérez Neira, Ana Isabel (Universitat Politècnica de Catalunya, 2020-06-16)
      Examen
      Accés restringit a la comunitat UPC

    • Experimental performance bounds of MIMO-FBMC/OQAM systems 

      Caus López, Marius; Pérez Neira, Ana Isabel (2010)
      Text en actes de congrés
      Accés restringit per política de l'editorial
      This paper addresses the application of filter bank multicarrier (FBMC) systems to multiple-input-multiple-output (MIMO) channels. In particular, it is investigated the FBMC modulation based on OQAM, known as FBMC/OQAM. ...

    • Experimental performance evaluation of a MAC protocol for cooperative ARQ scenarios 

      Verikoukis, Christos; Pérez Neira, Ana Isabel; Alonso Zárate, Jesús; Skiannis, Ch. (2009)
      Text en actes de congrés
      Accés obert
      This paper provides details and performance evaluation of the implementation of the Persistent Relay Carrier Sensing Multiple Access (PRCSMA) protocol for Cooperative ARQ (C-ARQ) scenarios using off-the-shelf wireless ...

    • Exploiting transmission spatial diversity in frequency selective systems with feedback channel 

      Pérez Neira, Ana Isabel; Pascual, T.; Lagunas Hernandez, Miguel A. (2003)
      Text en actes de congrés
      Accés obert
      In this paper we address the design of a multiple transmit antenna system in which the Channel State Information (CSI) at the transmitter is not perfect. Two different approaches are analyzed one based on the Minimization ...

    • Exploiting the cylic prefix for beamforming in OFDM receivers 

      Pérez Neira, Ana Isabel; Bartolomé Calvo, Diego (2002)
      Text en actes de congrés
      Accés obert
      ­Blind and semiblind antenna array algorithms are proposed for Orthogonal Frequency Division Multiplexing (OFDM) systems in the time domain. A blind technique is proposed for the maximization of the temporal Signal to Noise ...

    • Exploiting transmission spatial diversity in frequency selective systems with feedback channel 

      Pascual Iserte, Antonio; Pérez Neira, Ana Isabel; Lagunas Hernandez, Miguel A. (Institute of Electrical and Electronics Engineers (IEEE), 2003)
      Text en actes de congrés
      Accés restringit per política de l'editorial
      In this paper we address the design of a multiple transmit antenna system in which the Channel State Information (CSI) at the transmitter is not perfect. Two different approaches are analyzed: one based on the Minimization ...

    • Exploratory analysis of superposition coding and rate splitting for multibeam satellite systems 

      Caus, Marius; Pastore, Adriano; Navarro Rodero, Mònica; Ramirez, Tomás; Mosquera Nartallo, Carlos; Noels, Nele; Alagha, Nader; Pérez Neira, Ana Isabel (Institute of Electrical and Electronics Engineers (IEEE), 2018)
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      The adoption of aggressive frequency reuse schemes along with interference management techniques has become the leading paradigm in satellite communications to increase the spectral efficiency. In general terms, one cannot ...

    • FBMC-based random access signal design and detection for LEO base stations 

      Caus López, Màrius; Pérez Neira, Ana Isabel (Institute of Electrical and Electronics Engineers (IEEE), 2022-10-04)
      Article
      Accés obert
      The integration of non-terrestrial networks into the 5G ecosystem is mainly driven by the possibility of provisioning service in remote areas. In this context, the advent of flying base stations at the low Earth orbit (LEO) ...

    • FBMC/OQAM MIMO transceiver 

      Caus López, Marius; Mestre, Xavier; Gregoratti, David; Pérez Neira, Ana Isabel; Haardt, Martin; Cheng, Yao; Gomes Baltar, Leonardo (Elsevier, 2017-07-27)
      Capítol de llibre
      Accés restringit per política de l'editorial
      Orthogonal Waveforms and Filter Banks for Future Communication Systems provides an up-to-date account of orthogonal filter bank-based multicarrier (FBMC) systems and their applications in modern and future communications, ...

    • Flexible MIMO architectures: guidelines in the design of MIMO parameters 

      Payaró Llisterri, Miquel; Pascual Iserte, Antonio; Pérez Neira, Ana Isabel; Lagunas Hernandez, Miguel A. (2005)
      Text en actes de congrés
      Accés obert
      One of the multiple advantages of communicating through MIMO systems is their inherent ability to provide flexible configurations. Following this line of thought, in this paper we present a generic framework to study ...

    • Forward link interference mitigation in mobile interactive satellite systems 

      Henarejos Hernández, Pol; Vazquez, Miguel Angel; Cocco, Giuseppe; Pérez Neira, Ana Isabel (American Institute of Aeronautics and Astronautics (AIAA), 2013)
      Text en actes de congrés
      Accés restringit per política de l'editorial
      We present the results of the performance evaluation of polarization-time coding and soft interference cancellation in multi-beam satellite systems a ected by co-channel interference in realistic setups. The standard of ...

    • Fuzzy adaptive signal predistorter for OFDM signals 

      Bas Botella, Juan Antonio; Pérez Neira, Ana Isabel (Eurasip, 2000)
      Text en actes de congrés
      Accés obert
      This work develops an adaptive High Power Amplifier (HPA) predistorter that applies the fuzzy logic and fuzzy set theory. As Volterra and Fourier series models or Neural Networks, a fuzzy logic system (FLS) is a nonlinear ...