Research on High-Precision PGC Demodulation Method for Fabry-Perot Sensors Based on Shifted Sampling Pre-Calibration
Abstract
1. Introduction
2. Measurement Principles
2.1. The Carrier Phase Delay Problem in the PGC Algorithm
2.2. Signal Discretization Model and Phase Offset Mechanism
2.3. Sampling Rate Requirements for Complete Alignment
- (1)
- Mixing: Each sampling point multiplied with carrier (sine/cosine)—2 multiplications
- (2)
- Low-pass filtering: Assuming M-th order FIR filter—2 M multiply-accumulate operations per point (counted as 1 operation each)
- (3)
- Arctangent operation: Using approximation algorithms or lookup tables—about 10 operations per point
2.4. Pre-Alignment and Coefficient Compensation Co-Optimization
3. Experimental Analysis
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Li, Q.; Shao, J.; Wu, P.; Liang, J.; Lu, Y.; Zhang, M.; Qiu, Z. Research on High-Precision PGC Demodulation Method for Fabry-Perot Sensors Based on Shifted Sampling Pre-Calibration. Sensors 2025, 25, 5990. https://doi.org/10.3390/s25195990
Li Q, Shao J, Wu P, Liang J, Lu Y, Zhang M, Qiu Z. Research on High-Precision PGC Demodulation Method for Fabry-Perot Sensors Based on Shifted Sampling Pre-Calibration. Sensors. 2025; 25(19):5990. https://doi.org/10.3390/s25195990
Chicago/Turabian StyleLi, Qun, Jian Shao, Peng Wu, Jiabi Liang, Yuncai Lu, Meng Zhang, and Zongjia Qiu. 2025. "Research on High-Precision PGC Demodulation Method for Fabry-Perot Sensors Based on Shifted Sampling Pre-Calibration" Sensors 25, no. 19: 5990. https://doi.org/10.3390/s25195990
APA StyleLi, Q., Shao, J., Wu, P., Liang, J., Lu, Y., Zhang, M., & Qiu, Z. (2025). Research on High-Precision PGC Demodulation Method for Fabry-Perot Sensors Based on Shifted Sampling Pre-Calibration. Sensors, 25(19), 5990. https://doi.org/10.3390/s25195990