Author Affiliations
1School of Information Science and Engineering, Shandong University, Qingdao, Shandong 266237, China2Shandong Provincial Key Laboratory of Laser Technology and Application, Qingdao, Shandong 266237, China3Key Laboratory of Laser and Infrared System Integration Technology, Ministry of Education, Shandong University, Qingdao, Shandong 266237, Chinashow less
Fig. 1. Experimental setup of φ-OTDR system
Fig. 2. Gray scale transformation and iterative operation of original signal. (a) Original gray image constructed via consecutive Rayleigh curves; denoised gray images with single bright line indicating position information obtained after different iteration times, (b) 10 iteration times, (c) 30 iteration times, (d) 50 iteration times
Fig. 3. Location of original signal and after different iteration times. (a) Original Rayleigh backscattering traces; position information obtained after different iteration times, (b) 10 iteration times, (c) 30 iteration times, (d) 50 iteration times
Fig. 4. Vibration detection of 300 Hz processed by different denoising methods. (a) Moving average and moving differential method; (b) nonlocal mean method; (c) total variation algorithm
Fig. 5. Spatial resolution of the three methods. (a) Moving average and moving differential method; (b) nonlocal mean method; (c) total variation method
Fig. 6. Frequency information of the vibration event at PZT1
Fig. 7. Location information for detection of two PZTs’ vibrations by different methods. (a) Moving average and moving differential method; (b) nonlocal mean method; (c) total variation algorithm
Fig. 8. Frequency information for the vibration events. (a) PZT1; (b) PZT2
Fig. 9. Results of total variation algorithm for wideband signal processing. (a) Location information of vibration; (b) information of wideband signal spectral