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Since the invention of optical fiber cable data transmission using light has become ubiquitous in the past years. Nonlinear optical effects, which are hardly noticed in our daily life, have become crucial and highly influential for the design and performan ...
In this paper we perform an optimization of Brillouin optical time-domain analysis (BOTDA) sensors for achieving high resolution over long sensing ranges using distributed Raman amplification. By employing an optimized first-order bi-directional Raman ampl ...
A novel technique for interrogating photonic sensors based on long fiber Bragg gratings (FBGs) is presented and experimentally demonstrated, dedicated to detect the presence and the precise location of several spot events. The principle of operation is bas ...
We address the concept of virtual transparency in optical fibres and its application to dynamic range extension in distributed sensors. A sensor featuring 100 km measurement range with 2 meter resolution is experimentally demonstrated. ...
We review some recent results on the application of distributed Raman amplification schemes, including ultralong lasers, to the extension of the operating range and contrast in Brillouin optical time domain analysis (BOTDA) distributed sensing systems. ...
We propose and experimentally demonstrate an ultra-thin rigid endoscope (450 mu m diameter) based on a passive multimode optical fiber. We use digital phase conjugation to overcome the modal scrambling of the fiber to tightly focus and scan the laser light ...
A system to interrogate photonic sensors based on long weak fiber Bragg gratings (FBGs) is illustrated and experimentally demonstrated. The FBG sensor is able to detect and measure the precise location of several spot events. The principle of operation is ...
Institute of Electrical and Electronics Engineers2014
A new technique to investigate the spatial distribution of the reflection spectrum along fabricated long weak fiber Bragg gratings (FBG) is experimentally demonstrated, together with its potential applications for distributed fiber sensing and broadband si ...
Optical fibre sensors based on stimulated Brillouin scattering in optical fibers have now clearly demonstrated their excellent capability for long-range distributed strain and temperature measurements. The fibre is used as sensing element and a value for t ...
Distributed optical fiber Brillouin sensors provide innovative solutions for the monitoring of temperature and strain in large structures. The effective range of these sensors is typically of the order of 20–30 km, which limits their use in certain ...