Fig. 1. OFDR sensing system and monitoring prototype. (a) OFDR sensing system; (b) monitoring prototype

Fig. 2. Signal demodulation process of OFDR

Fig. 3. Schematic diagram of hydrophone probe shape measurement

Fig. 4. Experimental setup of fiber optic hydrophone probe deformation testing

Fig. 5. Simulation results of deformation of fiber optic hydrophone probe. (a) Outside of probe; (b) cross section of probe

Fig. 6. Wavelength shift caused by deformation of fiber optic hydrophone probe under different pressures. (a) Hydrophone probe 1 covered with soft rubber; (b) hydrophone probe 2 encapsulated by metal skeleton

Fig. 7. Constriction radius of fiber optic hydrophone probe and wavelength shift varying with pressure. (a) Hydrophone probe 1 covered with soft rubber; (b) hydrophone probe 2 encapsulated by metal skeleton

Fig. 8. Wavelength shift of fiber optic hydrophone probe 1 at pressure of 6 Mpa

Fig. 9. Reconstruction results of cross-sectional deformation of fiber optic hydrophone probes under different static pressures. (a) Hydrophone probe 1 covered with soft rubber; (b) hydrophone probe 2 encapsulated by metal skeleton

Fig. 10. Reconstruction result of cross-sectional deformation of fiber optic hydrophone probes under static pressure of 6 MPa