Fig. 1. Fiber optic strain rate sensor system. ASE, amplified spontaneous emission light source; ISO, isolator; CIR, circulator; 3×3 OC, 3×3 optical coupler; 1×2 OC, 1×2 optical coupler; FRM, Faraday rotator mirror. Demodulator integrates photodetectors, analog input modules, and embedded controllers. Red and blue lines represent optical fibers and communication cables, respectively.

Fig. 2. Demonstration of (a) three detection optical signals and (b) simulated strain rate and phase.

Fig. 3. Comparison of measured sensitivity and theoretical curve.

Fig. 4. Comparison of measured phase noise floor and equivalent phase noise of RIN.

Fig. 5. Phase noise recorded for 10 min.

Fig. 6. Recorded rectangular signal of 0.05 Hz.

Fig. 7. Dynamic range for dynamic measurement.

Fig. 8. Phase noise of FOSRS II recorded over 10 min.

Table 1. Simulation Parameters of FOSRS

Table 2. Comparison of FOSRS and DAS