Overcoming non-local effects and Brillouin threshold limitations in Brillouin optical time domain sensors

We demonstrate, for the first time to our knowledge, a Brillouin optical time domain analysis (BOTDA) sensor that is able to operate with a probe power larger than the Brillouin threshold of the deployed sensing fiber and that is free from detrimental non-local effects. The technique is based on a d...

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Detalles Bibliográficos
Autores: Ruiz Lombera, Rubén, Urricelqui Polvorinos, Javier, Sagüés García, Mikel, Mirapeix, Jesús, López Higuera, José Miguel, Loayssa Lara, Alayn
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2015
País:España
Institución:Universidad Pública de Navarra
Repositorio:Academica-e. Repositorio Institucional de la Universidad Pública de Navarra
OAI Identifier:oai:academica-e.unavarra.es:2454/22707
Acceso en línea:https://hdl.handle.net/2454/22707
Access Level:acceso abierto
Palabra clave:Brillouin distributed sensors
Brillouin optical time domain analysis
Non-local effects
Brillouin threshold
Optical fiber sensors
Stimulated Brillouin scattering
Descripción
Sumario:We demonstrate, for the first time to our knowledge, a Brillouin optical time domain analysis (BOTDA) sensor that is able to operate with a probe power larger than the Brillouin threshold of the deployed sensing fiber and that is free from detrimental non-local effects. The technique is based on a dual-probe-sideband setup in which an optical frequency modulation of the probe waves along the fiber is introduced. This makes the optical frequency of the Brillouin interactions induced by each probe wave on the pump to vary along the fiber so that two broadband Brillouin gain and loss spectra that perfectly compensate are created. As a consequence, the pulse spectral components remain undistorted avoiding non-local effects. Therefore, a very large probe power can be injected, which improves the signal-to-noise ratio in detection for long-range BOTDA. Moreover, the probe power can even exceed the Brillouin threshold limit due to their frequency modulation, which reduces the effective amplification of spontaneous Brillouin scattering in the fiber. Experiments demonstrate the technique in a 50-km sensing link in which 8 dBm of probe power is injected.