Sites prone to vibration waves such as mining, earthquake-prone areas or also border regions under vibration monitoring increasingly require vibration sensors with a wide frequency range and good sensitivity. In this article, we propose a fiber Bragg grating (FBG) vibration sensor based on a boundary (BM) or warning marker. By dimensioning the warning marker by adding a low reflectivity FBG vibration detector with a sensitive mass attached to the central part of the fiber, a vibration detection zone is thus set up. By producing several vibratory excitations of different frequencies in the main-axis of measurement of the sensor and in the cross-axis, the results show that the sensor resonance frequency is about 10 Hz, it has a good sensitivity, a wide working frequency range of 40-500 Hz in the main-axis of measurement and a good crossinterference test result of 2.4%. The sensor dynamic range is at least 39 dB and can achieve up to 67 dB for the precision of 0.4 pm, when the interrogator has readings taken at this wavelength precision.
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