Coherent Noise Reduction in High Visibility Phase-Sensitive Optical Time Domain Reflectometer for Distributed Sensing of Ultrasonic Waves

• Tipo: Artigo em Revista Científica Internacional
• Data: 2013

Autores

Martins, HF (Autor) Outra; Martin Lopez, S (Autor) Outra; Corredera, P (Autor) Outra; Filograno, ML (Autor) Outra; Frazao, O (Autor) FCUP; Gonzalez Herraez, M (Autor) Outra

Revista

Título: Journal of Lightwave Technology

Vol. 31

Páginas: 3631-3637

ISSN: 0733-8724

Editora: Optical Society of America

Indexação

ISI Web of Knowledge - 111 Citações

Scopus - 128 Citações

Outras Informações

ID Authenticus: P-009-SWH

DOI: 10.1109/jlt.2013.2286223

Abstract (EN): Phase-sensitive optical time domain reflectometry (phi OTDR) is a simple and effective tool allowing the distributed monitoring of vibrations along single-mode fibers. Up to now, phi OTDRs have been used mostly for the measurement of sub-kHz vibrations, normally in the context of intrusion sensing. In this paper, the authors present an experimental and theoretical description of a high-visibility phi OTDR and its performance when used for ultrasonic vibration measurements. The use of a semiconductor optical amplifier in the setup allows to suppress coherent noise and also to improve the spectral response of the pump pulses. These two advantages greatly decrease the detected intra-band noise thus allowing frequency measurements in the limits set by the time of flight of the light pulses while maintaining the simplicity of the scheme, as no post-processing, extremely high coherence lasers or coherent detection methods are required. The sensor was able to measure vibrations of up to 39.5 kHz with a resolution of 5 m over a range which could go up to 1.25 km. This is the first time to our knowledge that a fully distributed measurement of ultrasonic waves was achieved. The statistical behavior of the system was also described theoretically and characterized experimentally.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 7