New improvements for Brillouin optical time-domain reflectometry

Abstract

This paper presents new techniques designed to improve the performances of a BOTDR. The first one introduces a second pump to the sensor, thus doubling the Brillouin signal on the receiver. The second one uses image processing with a two-dimensional Gaussian filter whose parameters are defined. The last technique explores the possibilities offered by colour codes. The benefits of each, in terms of signal-to-noise ratio, is presented by comparing measurements over a distance range of 50km with a spatial resolution of 5m. These techniques can easily be combined and the global improvement is estimated at 10dB, compared to conventional sensors.

On the 2D Post-Processing of Brillouin Optical Time-Domain Analysis

“…Gaussian filters show several remarkable features, such as excellent time-frequency confinement as well as a straightforward design depending on a single parameter. Gaussian filters were initially proposed by Le Floch et al [25], demonstrating a simple and effective approach to enhance the performances of BOTDR setups. The filter tuning procedure here employed is similar, yet complementary by exploiting the separability of Gaussian filters to dissociate and analyze the contribution from each dimension to the total filtering operation.…”