Publication

High spatial and spectral resolution long-range sensing using Brillouin echoes

Luc Thévenaz, Stella Foaleng Mafang
2010
Journal Articles

Abstract

High spatial (~cm) and spectral (~MHz) resolution Brillouin sensing is realized with enhanced signal to noise ratio using a pre-activated acoustic field and an optical phase control over the interrogating pulse. Pre-activation of the acoustic field preserves the Brillouin natural linewidth and a differential gain technique extends the method to long ranges. Experimentally, fully resolved measurements of the Brillouin frequency shift of a 5 cm spot perturbation at the far end of a 5 km fibre have been performed with a frequency resolution of 3 MHz ( 2 sigma ), using a 500 ps (5 cm) pi phase shift pulse.

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https://infoscience.epfl.ch/entities/publication/f78c8e20-9445-44b9-870b-1dabd66b21a3

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Luc Thévenaz, Stella Foaleng Mafang
2010
Journal Articles

Abstract

Official source

https://infoscience.epfl.ch/entities/publication/f78c8e20-9445-44b9-870b-1dabd66b21a3

About this result

Related concepts (21)

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Signal-to-noise ratio (SNR or S/N) is a measure used in science and engineering that compares the level of a desired signal to the level of background noise. SNR is defined as the ratio of signal power to noise power, often expressed in decibels. A ratio higher than 1:1 (greater than 0 dB) indicates more signal than noise. SNR is an important parameter that affects the performance and quality of systems that process or transmit signals, such as communication systems, audio systems, radar systems, imaging systems, and data acquisition systems.

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