Fig. 1. Principle diagram of PGC-Arctan demodulation algorithm

Fig. 2. Principle diagram of PGC-MHM-LM demodulation algorithm

Fig. 3. Relationship between data points and nonlinear fitting curve by the LM algorithm

Fig. 4. Sign of phase signal recovery method

Fig. 5. Comparison of demodulated signals at different modulation depths. (a) C=1.50 rad; (b) C=2.63 rad

Fig. 6. Performance comparison of demodulation algorithms with 1.5‒3.0 rad modulation depth. (a) SINAD; (b) THD

Fig. 7. Comparison of demodulated signal waveforms with different phase delays. (a) θ=2π/5; (b) θ=π/2

Fig. 8. Performance comparison of demodulation algorithms with phase delay from 0 to π. (a) SINAD; (b) THD

Fig. 9. Time-domain waveform of the demodulated signal when the C value and phase delay change simultaneously

Fig. 10. Experimental setup of the PGC demodulation system

Fig. 11. Demodulation results of different algorithms. (a) Time-domain signal waveform; (b) PSD

Fig. 12. Performance comparison of different algorithms at phase delay singularities. (a) SINAD; (b) THD

Fig. 13. Linearity of the PGC-MHM-LM demodulation algorithm