Fig. 1. Structural diagram of PMFBG transverse load sensor based on microwave photonic filter

Fig. 2. Schematic of microwave photonic filter with two taps

Fig. 3. Simulated frequency responses of MPF at different TDDs

Fig. 4. Dual-wavelength laser output. (a) Reflection spectrum of PMFBG; (b) output spectrum of dual-wavelength laser

Fig. 5. Frequency response of the MPF with two taps

Fig. 6. Frequency responses of third notch at different transverse forces

Fig. 7. Fitted relationship between frequency of third notch of filter and transverse force

Fig. 8. Test results of stability. (a) Notch frequency versus temperature; (b) notch frequency versus axial strain