DEVICE AND METHOD FOR MEASURING THE DISTRIBUTION OF PHYSICAL QUANTITIES IN AN OPTICAL FIBRE

摘要

The invention relates to a device and method for measuring the distribution of physical quantities in an optical fibre, based on an improvement to the Brillouin optical time-domain analysis technique. The device and method improve the signal-to-noise ratio of the measurement signal detected through the use of heterodyne detection of said signal. In addition, the invention comprises the demodulation of the radio frequency signal resulting from the heterodyne detection, allowing both the modulus and the phase of the spectrum of the Brillouin interaction to be measured, thereby improving the characterisation of the spectrum.