Fig. 1. Diagram of WFBG sensing system and signal sequence. (a) Diagram of WFBG sensing system; (b) time sequence

Fig. 2. Interference intervals obtained based on AOM modulation signal and CWT for different modulation pulse widths and different numbers of WFBGs. (a) Interference intervals obtained based on AOM modulation signal for 300 ns modulation pulse width and 2-WFBG; (b) interference intervals obtained by CWT for 300 ns modulation pulse width and 2-WFBG; (c) interference intervals obtained by CWT for 450 ns modulation pulse width and 2-WFBG; (d) interference intervals obtained by CWT for 300 ns modulation pul

Fig. 3. Vibration signals of vibrating liquid column obtained by multiple measurements and characteristic values of interference intervals for different modulation pulse widths under the same vibration source. (a) 300 ns modulation pulse width; (b) 450 ns modulation pulse width

Fig. 4. Measured signals fitted by sine curve. (a) Fitting degree; (b) frequency; (c) amplitude; (d) average fitting degree, RMSE of frequency, and mean square error of amplitude

Fig. 5. Light intensity under different modulation pulse widths. (a) 300 ns; (b) 450 ns

Table 1. Sine curve fitting data of detected phase signals