Effect of Temperature on Frequency-shifted Interferometry Fiber Loop Ring-down Magnetic Field Sensing System

摘要

A fiber loop ring-down (FLRD) magnetic field sensing system combined with frequency-shifted interferometry (FSI) was proposed and the effect of temperature on its performance was experimentally demonstrated. The FS1-FLRD technique measures the light intensity decay rate (called the ring-down distance) in the space domain instead of in the time domain. Compared with conventional time domain FLRD scheme, FSI-FLRD technique greatly reduces the cost due to only need of inexpensive continuous-wave laser and slow detection. The tapered single mode fiber surrounded by magnetic fluid (MF) was utilized to construct the sensor head for temperature measurement. Different temperature was generated due to the thermal effect of MF and the temperature was obtained by measuring the ring-down distance. The experimental results indicated that a sensitivity of 0.31 /(mm ·°C) was achieved.