The invention relates to a Brillouin Optical
Time Domain Analysis (BOTDA)-based sensing device and method. The device comprises a
supercontinuum source, three tunable light filters, three 1x2 opticalfiber couplers, two polarization controllers, two high-speed electrooptical modulators, a
microwave signal source, three light amplifiers, a light scrambler, an optoisolator, a sensing
optical fiber,an
optical circulator, a
pulse generator, three photoelectric detectors, a
data acquisition card and a computer. The BOTDA-based sensing device can enlarge the
dynamic range of BOTDA, prolongs a measuring distance of an
optical fiber and improves the spatial resolution of the
system; furthermore, the device detects optical signals in opposite directions, which solves the problems that the power isgradually lost and the detection range is limited for a traditional BOTDA single-channel
signal with the prolonging of the distance of the
optical fiber; by the adoption of the
supercontinuum source,the device has a spectral range wider than that of a
tunable laser device, and can cooperate with the light filters to generate
tunable laser with adjustable wavelengths and changeable spatial resolutions; and the
supercontinuum source is used as a pump
light source in the device, so as to solve the problem of a limited measuring distance of a narrow-band
laser device and enhance the stability ofthe
system.