Fig. 1. Schematic of frequency-modulated continuous wave laser interference pressure sensor

Fig. 2. Variation of angular frequency of reference and signal waves with time

Fig. 3. Sawtooth wave frequency modulation (up) and frequency-modulated continuous wave beat frequency signal (below) waveforms

Fig. 4. Flow chart of demodulation of initial phase of beat signal of frequency-modulated continuous wave optical fiber pressure sensor

Fig. 5. Experimental system diagram of diaphragm frequency-modulated continuous wave optical fiber pressure sensor

Fig. 6. Sensitivity measurement of frequency-modulated continuous wave optical fiber pressure sensor

Fig. 7. Stability measurement of sensor at different pressures and the same temperature (25 ℃) of the thermostat. (a) 0 kPa; (b) 200 kPa; (c) 402 kPa; (d) 602 kPa

Fig. 8. Flow chart of system error elimination

Fig. 9. Random error distribution

Fig. 10. Normal distribution of random error

Fig. 11. Variation of F-P cavity length of Fabry-Perot cavity with temperature