DISTRIBUTED FIBER OPTIC SENSING SYSTEM AND METHOD BASED ON STIMULATED BRILLOUIN SCATTERING

摘要

System and method of distributed sensing based on Brillouin stimulated scattering on optical fiber (3), consisting of separating the two signals of which the probe signal is composed and obtaining the difference between the stimulated amplification band (8) and the attenuation band (9), or vice-versa. In this way a signal is obtained with greater amplitude than in the case of detection being performed with a single band. Thus the signal-to-noise ratio is improved in the sensor signal, dynamic range and the range is increased and the uncertainty of the measurement is decreased. It also eliminates the common noise present in the two bands of the probe signal and, in the case of using a balanced detector in detection, it improves the saturation characteristics of the detector, being able to achieve much larger signal amplitudes than in the conventional case.

主权项

1. System of distributed sensing on an optical fiber (3) based on stimulated Brillouin scattering comprising:
light emission means (1, 2) adapted to be connected to the optical fiber (3) by means of an input/output port (4) and an input port (7), and to generate a pump signal and a probe signal adapted to generate the effect of stimulated Brillouin scattering in the optical fiber (3);characterized in that it also comprises:
discrimination means (5) coupled to the input/output port (4) and adapted to separate an amplified band (8) and an attenuated band (9) generated by the Brillouin scattering; a balanced detector (10) coupled to the discrimination means (5) and adapted to detect a power difference between the amplified band (8) and the attenuated band (9); and analysis means adapted to calculate the distributed sensing from the power difference detected.