A distributed optical fiber acoustic sensor based on in-line Sagnac is presented.After clockwise and counterclockwise light waves are recombined,interference in3X3coupler is produced.The acoustic sensor uses photo det...A distributed optical fiber acoustic sensor based on in-line Sagnac is presented.After clockwise and counterclockwise light waves are recombined,interference in3X3coupler is produced.The acoustic sensor uses photo detector(PD),data acquisition card,filter and amplification to realize photo electric conversion and recover acoustic signal.To study the performance of this acoustic sensor,localization principle based on null frequency is analyzed.To reveal null frequencies from the acoustic disturbance position,a fast Fourier transform(F F T)is applied to transform time domain signal data into frequency domain signal.The results demonstrate that the Sagnac distributed optical fiber sensor can retransmit acoustic signal and the location performance is verified by simulation and experiment.展开更多
基金Key Science and Technology Research Project based on Coal of Shanxi Province(No.MQ2014-09)Coal-Bed Methane Joint Research Fund of Shanxi Province(No.2016012011)Shanxi Scholarship Council of China(No.2016-035)
文摘A distributed optical fiber acoustic sensor based on in-line Sagnac is presented.After clockwise and counterclockwise light waves are recombined,interference in3X3coupler is produced.The acoustic sensor uses photo detector(PD),data acquisition card,filter and amplification to realize photo electric conversion and recover acoustic signal.To study the performance of this acoustic sensor,localization principle based on null frequency is analyzed.To reveal null frequencies from the acoustic disturbance position,a fast Fourier transform(F F T)is applied to transform time domain signal data into frequency domain signal.The results demonstrate that the Sagnac distributed optical fiber sensor can retransmit acoustic signal and the location performance is verified by simulation and experiment.
