Now showing items 1-2 of 2

    • Frequency modulated continuous wave system for optical fiber intensity sensors with optical amplification 

      Pérez Herrera, Rosa Ana Upna; Frazão, Orlando; Santos, José Luís; Araújo, Francisco Moita; Ferreira, Luis Alberto; Baptista, José Manuel; López-Amo Sáinz, Manuel Upna (IEEE, 2009)   Artículo / Artikulua  OpenAccess
      We report on the use of erbium doped fiber (EDF) amplification to enhance a frequency modulated continuous wave (FMCW) technique for referencing optical intensity sensors located between two Bragg grating structures. The ...
    • Sensitivity improvement of a humidity sensor based on silica nanospheres on a long-period fiber grating 

      Viegas, Diana; Goicoechea Fernández, Javier Upna; Santos, José Luís; Araújo, Francisco Moita; Ferreira, Luis Alberto; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (MDPI, 2009)   Artículo / Artikulua  OpenAccess
      This work addresses a new configuration that improves the sensitivity of a humidity sensor based on a long-period fiber grating coated with a SiO(2)-nanospheres film. An intermediate higher refractive index overlay, ...