Patent ID: 11940375
Assignee: DALIAN UNIVERSITY OF TECHNOLOGY
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 4:
5. The sensing system according to claim 4, wherein a method for determining the low-interference frequency as the working frequency in step 2 is as follows: the detection light emitted by the detection light source (6) is incident into the fiber-optic photoacoustic sensing probe (5) after passing through the fiber-optic circulator (7), and returned Fabry-Perot interference signal light is received by the photodetector (8) after passing through the fiber-optic circulator (7); the signal collection and processing circuit (1) collects a photoelectric signal converted by the photodetector (8), restores an acoustic wave signal by using the interference-intensity demodulation method, and performs spectrum analysis on the detected ambient noise through fast Fourier transform; and the low-interference frequency in the ambient noise is selected, within a high frequency range and based on a frequency response of the fiber-optic photoacoustic sensing probe (5) to an external acoustic wave and a spectrum analysis result, as the working frequency of photoacoustic measurement.