Now showing items 1-6 of 6

  • A VLC channel model for underground mining environments with scattering and shadowing 

    Palacios-Játiva, Pablo; Azurdia-Meza, Cesar A.; Sánchez, Iván; Seguel, Fabian; Zabala-Blanco, David; Dehghan Firoozabadi, Ali; Gutiérrez, Carlos A.; Soto, Ismael (2020)
    Underground mining is an industry that preserves the miners' safety and efficiency in their work using wireless communication systems as a tool. In addition to communication links characterized by radio frequency signals, ...

  • Empirical path loss distribution for visible light communications in underground mines 

    Zabala-Blanco, David; Palacios Játiva, Pablo; Azurdia, Cesar; Román, Milton; Seguel, Fabián; Soto, Ismael (2020)
    Visible light communication (VLC) systems allow communication and lighting simultaneously. This advantage presents VLC as an emerging technology to provide reliable communication in harsh environments, such as underground ...

  • ICI reduction by using the improved double-jump 1 pulse in MQAM-OFDM schemes 

    Zabala-Blanco, David; Azurdia-Meza, Cesar A.; Montejo-Sánchez, Samuel; Dehghan Firoozabadi, Ali; Palacios Játiva, Pablo; Soto, Ismael (2020)
    Orthogonal frequency division multiplexing (OFDM) is sensitive to frequency offset since it causes inter-carrier interference (ICI). Frequency offset results from the receiver's crystal oscillator inaccuracy, Doppler spread, ...

  • Improved double-jump 2 pulse to compensate frequency offset in MQAM-OFDM systems 

    Zabala-Blanco, David; Azurdia-Meza, Cesar A.; Palacios-Játiva, Pablo (2020)
    Orthogonal frequency division multiplexing (OFDM) is severely affected by the frequency offset because of it causes inter-carrier interference (ICI). ICI can be diminished with the assistance of any pulse that complies the ...

  • Multiresolution speech enhancement based on proposed circular nested microphone array in combination with sub-band affine projection algorithm 

    Dehghan Firoozabadi, Ali; Irarrazaval, Pablo; Adasme, Pablo; Zabala-Blanco, David; Durney, Hugo; Sanhueza, Miguel; Palacios-Játiva, Pablo; Azurdia-Meza, Cesar A. (2020)
    Speech enhancement is one of the most important fields in audio and speech signal processing. The speech enhancement methods are divided into the single and multi-channel algorithms. The multi-channel methods increase the ...

  • Performance analysis of OFDM-Based VLC schemes in NLOS channels 

    Palacios-Játiva, Pablo; Azurdia-Meza, Cesar A.; Román Cañizares, Milton; Zabala-Blanco, David; Montejo-Sánchez, Samuel (2020)
    In this paper, several Orthogonal frequency division multiplexing (OFDM)-based Visible light Communications (VLC) techniques designed for intensity modulation/direct detection (IM/DD) are evaluated and compared for various ...