Abstract
In this study, we propose a temperature-independent fiber-Bragg-grating magnetic field sensing system, based on a novel optical power detection scheme. Implemented with two spectrally slightly separated fiber Bragg gratings, which were closely placed side by side, except for this, one is stuck on the magnetostrictive rod with epoxy at both ends, and the other is stuck on another metal rod which can't be affected by magnetic field to form a temperature-independent magnetic field sensor unit. Instead of conventional wavelength interrogation techniques, magnetic field can be simply calibrated by monitoring the reflected power of the system. Magnetic field measurement up to 132mT with high linearity (±0.2 %), good sensitivity (1mT ), and high thermal stability (±0.3 %) in the temperature range from 27℃~85℃ was achieved here.