Research on Fiber Optic Sensor and Demodulation Algorithm for Temperature and Pressure Dual Parameter Measurement

This With the further development of industrial fields such as ocean exploration and oil and gas extraction, there is an urgent need for temperature and pressure sensors to monitor temperature and pressure changes in these industrial processes to ensure safety. Traditional electrical sensors are limited in their range of use due to their lack of resistance to electromagnetic interference and inherent safety, while fiber optic temperature and pressure sensors are receiving increasing research due to their advantages. However, most current fiber optic temperature and pressure sensors rely on manual preparation by researchers, which makes it difficult to guarantee their performance. In addition, there may be temperature cross talk during pressure measurement, leading to inaccurate pressure measurement. There are still some problems that need to be solved in terms of demodulation algorithms, which ultimately limit the application of fiber optic temperature and pressure sensors. In response to the above issues, this article focuses on the design of sensors for simultaneous measurement of temperature and pressure. An integrated fiber optic temperature and pressure sensor is proposed, along with an improved fitting extension minimum mean square error cross-correlation demodulation algorithm for the demodulation of composite Fabry Perot cavity fiber optic temperature and pressure sensors. This algorithm addresses the demodulation jump issue of traditional algorithms and has been finally packaged and tested underwater for practical applications.