Fig. 1. Hardware diagram of improved symmetric demodulation technology system

Fig. 2. Flowchart of signal demodulation of improved symmetric demodulation technique

Fig. 3. Simulation results for static/dynamic composite signal demodulation. (a) Input signals and output signals; (b)-(d) enlarged images of areas indicated by solid boxes in Fig. 3(a)

Fig. 4. Demodulation results of static/dynamic composite signals. (a) Recovered static/dynamic composite signals; (b)–(e) enlarged images of areas indicated by solid boxes in Fig. 4(a)

Fig. 5. Power spectrum of dynamic component of signal c-sym

Fig. 6. Demodulation results for static/dynamic composite signal with cavity length change larger than 100 μm. (a) Recovered static/dynamic composite signals; (b)(c) enlarged images of areas indicated by solid boxes in Fig. 6(a)