Distributed Fiber Optic Sensor for Accurate Liquid Level Monitoring Based on Optical Frequency Domain Reflectometry

This study presents a highly accurate liquid level monitoring system utilizing optical frequency domain reflectometry (OFDR). The proposed system detects environmental characteristics along the length of the optical fiber and determines liquid levels in real time using a dynamic time warping (DTW) algorithm. This method facilitated the development of a distributed fiber optic liquid level sensor and its associated measurement system. Comprehensive testing of system stability, static accuracy, and dynamic accuracy was conducted. Experimental results demonstrated that the OFDR-based system achieved a stability of 0.44 mm , a static accuracy of 0.87 mm , and a dynamic accuracy of 0.93 mm over a length of 20 m . These results indicate the system’s capability to perform highly accurate and stable liquid level measurements.