Distributed vibration sensing over 125 km with enhanced SNR using ΦOTDR over a URFL cavity

We describe the use of a phase-sensitive optical time domain reflectometer (ΦOTDR) over an ultra-long Raman fiber laser cavity allowing fully distributed detection of vibrations over 125 km. Compared to a first-order Raman-assisted ΦOTDR, this scheme shows an enhanced signal-to-noise ratio (SNR). Th...

Descripción completa

Detalles Bibliográficos
Autores: Fidalgo Martins, Hugo|||0000-0003-3927-8125, Martín López, Sonia|||0000-0001-5203-6206, Corredera Guillén, Pedro, Ania Castañón, Juan Diego, Frazão, O., González Herráez, Miguel|||0000-0003-2555-2971
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Universidad de Alcalá (UAH)
Repositorio:e_Buah Biblioteca Digital Universidad de Alcalá
Idioma:inglés
OAI Identifier:oai:ebuah.uah.es:10017/26309
Acceso en línea:http://hdl.handle.net/10017/26309
https://dx.doi.org/10.1109/JLT.2015.2396359
Access Level:acceso abierto
Palabra clave:Distributed sensor
Optical fiber sensors
Raman scattering
Vibration sensor
Phase sensitive OTDR
Electrónica
Electronics
Descripción
Sumario:We describe the use of a phase-sensitive optical time domain reflectometer (ΦOTDR) over an ultra-long Raman fiber laser cavity allowing fully distributed detection of vibrations over 125 km. Compared to a first-order Raman-assisted ΦOTDR, this scheme shows an enhanced signal-to-noise ratio (SNR). This is due to the fact that the relative intensity noise introduced by the Raman amplification is mostly transferred to a lower frequency range, where the balanced detection implemented in the setup provides better suppression of the common-mode noise. The sensor was able to measure vibrations of up to 380 Hz (limit set by the time of flight of light pulses) in a distance of 125 km with a resolution of 10 m and an average SNR of 8 dB with no postprocessing. This implies a >3 dB improvement in SNR over a first-order Raman-assisted setup with similar characteristics