Listar Grupo de Tecnoloxía Electrónica e Comunicacións (GTEC) por título

Mostrando ítems 41-60 de 225

    • An IoT system for a smart campus: Challenges and solutions illustrated over several real-world use cases 

      Domínguez-Bolaño, Tomás; Barral Vales, Valentín; Escudero, Carlos J.; García-Naya, José A. (Elsevier, 2024-04)
      [Abstract]: This article discusses the development of an IoT system for monitoring and controlling various devices and systems from different vendors. The authors considered key challenges in IoT projects, such as ...

    • An overview of IoT architectures, technologies, and existing open-source projects 

      Domínguez-Bolaño, Tomás; Campos Fernández, Omar; Barral Vales, Valentín; Escudero, Carlos J.; García-Naya, José A. (Elsevier, 2022-11)
      [Abstract]: Today’s needs for monitoring and control of different devices in organizations require an Internet of Things (IoT) platform that can integrate heterogeneous elements provided by multiple vendors and using ...

    • Analog Beamforming Using Time-Modulated Arrays With Digitally Preprocessed Rectangular Sequences 

      Maneiro-Catoira, Roberto; Brégains, Julio; García-Naya, José A.; Castedo, Luis (Institute of Electrical and Electronics Engineers, 2018-03)
      [Abstract]: Conventional time-modulated arrays are based on the application of variable-width periodical rectangular pulses (easily implemented with radio frequency switches) to the individual antenna excitations. However, ...

    • Analog joint source-channel coding over MIMO channels 

      Vázquez-Araújo, Francisco J.; Fresnedo, Óscar; Castedo, Luis; Garcia-Frias, Javier (SpringerOpen & European Association for Signal Processing, 2014-02)
      [Abstract]: Analog joint source-channel coding (JSCC) is a communication strategy that does not follow the separation principle of conventional digital systems but has been shown to approach the optimal distortion-cost ...

    • Analog Transmission of Correlated Sources Over BC With Distortion Balancing 

      Suárez-Casal, Pedro; Fresnedo, Óscar; Castedo, Luis; Garcia-Frias, Javier (Institute of Electrical and Electronics Engineers, 2017-11)
      [Abstract]: Analog transmission of correlated information over Gaussian broadcast channels (BCs) using analog joint source- channel coding (JSCC) is addressed. This communication strategy has attractive advantages, such ...

    • Analog Transmission of Correlated Sources Over Fading SIMO Multiple Access Channels 

      Suárez-Casal, Pedro; Fresnedo, Óscar; Castedo, Luis; Garcia-Frias, Javier (Institute of Electrical and Electronics Engineers, 2017-07)
      [Abstract]: Joint source-channel coding for discrete-time analog sources is an appealing transmission approach because of its extremely low delay and complexity. When the users access the channel orthogonally, analog ...

    • Analog Transmission of Spatio-Temporal Correlated Sources Over MAC With Modulo Mappings 

      Suárez-Casal, Pedro; Fresnedo, Óscar; Castedo, Luis (Institute of Electrical and Electronics Engineers, 2018-05)
      [Abstract]: Modulo mappings is an appealing scheme for the analog transmission of spatially correlated discrete-time analog source symbols over multiple access channels. In this letter, we show that the modulo mappings are ...

    • Analog Video Encoding and Quality Evaluation 

      Balsa, José; Fresnedo, Óscar; García-Naya, José A.; Domínguez-Bolaño, Tomás; Castedo, Luis (M D P I AG, 2019-07-23)
      [Abstract] The most widespread analog video encoding systems in the literature are based on the use of the 2D and 3D DCT. These systems use both transformations indistinctly without assessing their suitability. In this ...

    • Analogue joint source-channel coding for multiple input multiple output–orthogonal frequency division multiplexing systems 

      Fresnedo, Óscar; Vázquez-Araújo, Francisco J.; Castedo, Luis; Garcia-Frias, Javier (Wiley, 2016)
      [Abstract]: Analogue joint source-channel coding (JSCC) has been shown to approach the optimal distortion-cost trade-off when transmitting over additive white Gaussian noise channels. In this work, we consider analogue ...

    • Analysis of the Influence Subjective Human Parameters in the Calculation of Thermal Comfort and Energy Consumption of Buildings 

      Robledo Fava, Roberto; Hernández Luna, Mónica Cynthia; Fernández de Córdoba, Pedro; Michinel, Humberto; Zaragoza, Sonia; Castillo-Guzman, A.; Selvas-Aguilar, Romeo (M D P I AG, 2019)
      [Abstract] In the present work, we analyze the influence of the designer’s choice of values for the human metabolic index (met) and insulation by clothing (clo) that can be selected within the ISO 7730 for the calculation ...

    • Analysis, Design and Empirical Validation of a Smart Campus Based on LoRaWAN 

      Fraga-Lamas, Paula; Celaya-Echarri, Mikel; López Iturri, Peio; Fernández-Caramés, Tiago M.; Azpilicueta, Leyre; Aguirre, Erik; Suárez-Albela, Manuel; Falcone, Francisco; Castedo, Luis (MDPI, 2019)
      [Abstract] Internet of Things (IoT) applications for smart environments demand challenging requirements for wireless networks in terms of security, coverage, availability, power consumption, and scalability. The technologies ...

    • Analysis, Design and Practical Validation of an Augmented Reality Teaching System Based on Microsoft HoloLens 2 and Edge Computing 

      Vidal-Balea, Aida; Blanco, Óscar; Picallo, Imanol; Celaya-Echarri, Mikel; Fraga-Lamas, Paula; López Iturri, Peio; Azpilicueta, Leyre; Falcone, Francisco; Fernández-Caramés, Tiago M. (MDPI, 2020-11-14)
      [Absctract]: In recent years, the education sector has incorporated the use of new technologies and computing devices into classrooms, which allowed for implementing new ways for enhancing teaching and learning. One of ...

    • Analysis, Synthesis, and Diagnostics of Antenna Arrays through Complex-Valued Neural Networks 

      Brégains, Julio; Ares Pena, F. J. (John Wiley & Sons, Inc., 2006-08)
      [Abstract] It is shown in this paper that when artificial neural networks are extended to be complex valued, they can be incorporated as a very powerful and effective tool in the analysis, synthesis, and diagnostics of ...

    • Aplicación web para evaluación y seguimiento del rendimiento de asignaturas y titulaciones universitarias 

      Dapena, Adriana; García-Naya, José A.; Castro-Castro, Paula-María; Pan, Christopher (Universidade de Vigo, Facultade de Ciencias da Educacion, 2010)
      [Summary] The adaptation of the university studies to the current European Higher Education Area (EHEA) requires the set up of mechanisms, which allow performance evaluation of the subjects compounding the new university ...

    • Application of Time Modulation in the Synthesis of Sum and Difference Patterns by Using Linear Arrays 

      Fondevila, J.; Brégains, Julio; Ares Pena, F. J.; Moreno Piquero, E. (John Wiley & Sons, Inc., 2006-05)
      [Abstract] In this paper, time modulation is applied to a small number of elements of a linear array that radiates either sum or difference patterns, in order to take control over their sidelobe levels. The simulated ...

    • Architecture for Multi-Technology Real-Time Location Systems 

      Rodas, Javier; Barral Vales, Valentín; Escudero, Carlos J. (Multidisciplinary Digital Publishing Institute, 2013)
      [Abstract]The rising popularity of location-based services has prompted considerable research in the field of indoor location systems. Since there is no single technology to support these systems, it is necessary to consider ...

    • Avoiding Interference in Planar Arrays through the Use of Artificial Neural Networks 

      Brégains, Julio; Dorado, Julián; Gestal, M.; Rodríguez, J. A.; Ares, F.; Pazos, A. (Institute of Electrical and Electronics Engineers, 2002-08)
      [Abstract] This article implements an artificial neural network to find, through computer simulation, the excitations of a square planar array. The array is composed of 52 uniformly spaced subarrays, and has a quasi- in ...

    • Beam Reconfiguration of Linear Arrays Using Parasitic Elements 

      Rodríguez, J. A.; Trastoy, A.; Brégains, Julio; Ares Pena, F. J.; Franceschetti, G. (The Institution of Engineering and Technology, 2006-02-13)
      [Abstrac] An innovative method for linear arrays beam reconfiguration is presented. This pattern reconfigurability is achieved by a mechanical displacement of a parasitic array located in front of an active one. Two worked ...

    • Bit Error Probability and Capacity Bound of OFDM Systems in Deterministic Doubly-Selective Channels 

      Domínguez-Bolaño, Tomás; Rodríguez Piñeiro, José; García-Naya, José A.; Castedo, Luis (Institute of Electrical and Electronics Engineers, 2020-10)
      [Abstract]: Doubly-selective channels, such as those that occur when the transmitter and the receiver move relative to each other at high speeds, are a key scenario for fifth generation (5G) cellular systems, which are ...

    • Blind channel identification in Alamouti coded systems: a comparative study of eigendecomposition methods in indoor transmissions at 2.4 GHz 

      Pérez-Iglesias, Héctor J.; García-Naya, José A.; Dapena, Adriana; Castedo, Luis; Zarzoso, Vicente (Wiley, 2008)
      [Abstract]: This paper focuses on blind channel estimation in Alamouti coded systems with one receiving antenna working in indoor scenarios where the flat fading assumption is reasonable. A comparative study of several ...