Now showing items 1-16 of 16

    • A diffusion-based distributed EM algorithm for density estimation in wireless sensor networks 

      Silva Pereira, Silvana; López Valcarce, Roberto; Pagès Zamora, Alba Maria (Institute of Electrical and Electronics Engineers (IEEE), 2013)
      Conference report
      Restricted access - publisher's policy
      We address the problem of distributed estimation of a parameter from a set of noisy observations collected by a sensor network, assuming that some sensors may be subject to data failures and report only noise. In such ...
    • A diffusion-based em algorithm for distributed estimation in unreliable sensor networks 

      Silva Pereira, Silvana; López Valcarce, Roberto; Pagès Zamora, Alba Maria (2013-01)
      Article
      Restricted access - publisher's policy
      We address the problem of distributed estimation of a parameter from a set of noisy observations collected by a sensor network, assuming that some sensors may be subject to data failures and report only noise. In such ...
    • Cramer-Rao bounds for SNR estimation of oversampled linearly modulated signals 

      López Valcarce, Roberto; Villares Piera, Nemesio Javier; Riba Sagarra, Jaume; Gappmair, Wilfried; Mosquera Nartallo, Carlos (2015-04-01)
      Article
      Open Access
      Most signal-to-noise ratio (SNR) estimators use the receiver matched filter output sampled at the symbol rate, an approach which does not preserve all information in the analog waveform due to aliasing. Thus, it is relevant ...
    • Distributed AOA-based source positioning in NLOS with sensor networks 

      Giménez Febrer, Pedro Juan; Pagès Zamora, Alba Maria; Silva Pereira, Silvana; López Valcarce, Roberto (Institute of Electrical and Electronics Engineers (IEEE), 2015)
      Conference lecture
      Open Access
      This paper focuses on the problem of positioning a source using angle-of-arrival measurements taken by a wireless sensor network in which some of the nodes experience non lineof-sight (LOS) propagation conditions. In ...
    • Distributed multivariate regression with unknown noise covariance in the presence of outliers: an MDL approach 

      López Valcarce, Roberto; Romero Gonzalez, Daniel; Sala Álvarez, José; Pagès Zamora, Alba Maria (Institute of Electrical and Electronics Engineers (IEEE), 2016)
      Conference report
      Open Access
      We consider the problem of estimating the coefficients in a multivariable linear model by means of a wireless sensor network which may be affected by anomalous measurements. The noise covariance matrices at the different ...
    • Distributed TLS estimation under random data faults 

      Silva Pereira, Silvana; Pagès Zamora, Alba Maria; López Valcarce, Roberto (Institute of Electrical and Electronics Engineers (IEEE), 2015)
      Conference report
      Restricted access - publisher's policy
      This paper addresses the problem of distributed estimation of a parameter vector in the presence of noisy input and noisy output data, as well as data faults, performed by a wireless sensor network in which only local ...
    • Distributed Total Least Squares estimation over networks 

      López Valcarce, Roberto; Silva Pereira, Silvana; Pagès Zamora, Alba Maria (Institute of Electrical and Electronics Engineers (IEEE), 2014)
      Conference report
      Restricted access - publisher's policy
      We consider Total Least Squares (TLS) estimation in a network in which each node has access to a subset of equations of an overdetermined linear system. Previous distributed approaches require that the number of equations ...
    • Expectation–maximisation based distributed estimation in sensor networks 

      López Valcarce, Roberto; Pagès Zamora, Alba Maria (Institution of Engineering and Technology, 2019-03-01)
      Part of book or chapter of book
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      Estimating the unknown parameters of a statistical model based on the observations collected by a sensor network is an important problem with application in multiple fields. In this setting, distributed processing, by which ...
    • How to implement doubly-stochastic matrices for consensus-based distributed algorithms 

      Valcarcel Macua, Sergio; Moreno Leon, Carlos; Samuel Romero, Jhoan; Silva Pereira, Silvana; Zazo Muncharaz, Javier; Pagès Zamora, Alba Maria; López Valcarce, Roberto; Zazo Bello, Santiago (Institute of Electrical and Electronics Engineers (IEEE), 2014)
      Conference report
      Restricted access - publisher's policy
      Doubly-stochastic matrices are usually required by consensus-based distributed algorithms. We propose a simple and efficient protocol and present some guidelines for implementing doubly-stochastic combination matrices even ...
    • Multiantenna GLR detection of rank-one signals with known power spectral shape under spatially uncorrelated noise 

      Sala Álvarez, José; Vázquez Vilar, Gonzalo; López Valcarce, Roberto; Sedighi, Saeid; Taherpour, Abbas (2016-12-01)
      Article
      Open Access
      We establish the generalized likelihood ratio (GLR) test for a Gaussian signal of known power spectral shape and unknown rank-one spatial signature in additive white Gaussian noise with an unknown diagonal spatial ...
    • Multiantenna GLR detection of rank-one signals with known power spectrum in white noise with unknown spatial correlation 

      Sala Álvarez, José; Vázquez Vilar, Gonzalo; López Valcarce, Roberto (2012-06)
      Article
      Restricted access - publisher's policy
      Multiple-antenna detection of a Gaussian signal with spatial rank one in temporally white Gaussian noise with arbitrary and unknown spatial covariance is considered. This is motivated by spectrum sensing problems in the ...
    • Multiantenna spectrum sensing exploiting spectral a priori information 

      Vázquez Vilar, Gonzalo; López Valcarce, Roberto; Sala Álvarez, José (2011-12)
      Article
      Restricted access - publisher's policy
      Dynamic Spectrum Access (DSA) is receiving considerable interest as a means to improve spectral usage in licensed bands. In order to avoid interference to licensed users, spectrum sensing has emerged as an enabling technology ...
    • Multiantenna spectrum sensing for cognitive radio: overcoming noise uncertainty 

      López Valcarce, Roberto; Vázquez Vilar, Gonzalo; Sala Álvarez, José (2010)
      Conference report
      Open Access
      Spectrum sensing is a key ingredient of the dynamic spectrum access paradigm, but it needs powerful detectors operating at SNRs well below the decodability levels of primary signals. Noise uncertainty poses a significant ...
    • Online EM-based distributed estimation in sensor networks with faulty nodes 

      Giménez Febrer, Pedro Juan; Pagès Zamora, Alba Maria; López Valcarce, Roberto (Institute of Electrical and Electronics Engineers (IEEE), 2016)
      Conference lecture
      Restricted access - publisher's policy
      This paper focuses on the problem of the distributed estimation of a parameter vector based on noisy observations regularly acquired by the nodes of a wireless sensor network and assuming that some of the nodes have faulty ...
    • Parameter estimation in wireless sensor networks with faulty transducers: a distributed EM approach 

      Silva Pereira, Silvana; López Valcarce, Roberto; Pagès Zamora, Alba Maria (2018-03-01)
      Article
      Open Access
      We address the problem of distributed estimation of a vector-valued parameter performed by a wireless sensor network in the presence of noisy observations which may be unreliable due to faulty transducers. The proposed ...
    • Robust clustering of data collected via crowdsourcing 

      Pagès Zamora, Alba Maria; Giannakis, Georgios B.; López Valcarce, Roberto; Giménez Febrer, Pedro Juan (2017)
      Conference report
      Open Access
      Crowdsourcing approaches rely on the collection of multiple individuals to solve problems that require analysis of large data sets in a timely accurate manner. The inexperience of participants or annotators motivates well ...