| 摘要 |
PROBLEM TO BE SOLVED: To provide a measuring method of frequency shift of a Brillouin scattering light and a device, capable of detecting frequency variation, in real time at arbitrary measuring point by measuring the frequency shift of the Brillouin scattering light at a high speed with inexpensive parts constituent. SOLUTION: In the measuring method of frequency shift of Brillouin scattering light generated in an optical fiber, pulsed light is emitted to the optical fiber from an optical section, the returned Brillouin scattering light from the optical fiber is made to enter the optical section, the Brillouin scattered light is converted into an electrical signal at light-receiving section, electrical signal and the signal outputted from an oscillator are blended with a mixer to be output; higher frequency components of the blended signal are removed at a filtering section; the signal outputted from filtering section is sampled at a signal processing section; and then by using the sampling data obtained is used frequency shift is obtained by means of fast-Fourier transformation. COPYRIGHT: (C)2007,JPO&INPIT
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