Development of an Optical Fiber Sensor Interrogation System for Vibration Analysis

Figure 6

Optical spectrum and standard deviation. (a) FBG-scan 700 interrogator, (b) VCSEL based interrogator. It can be observed that the SNR of the FBG-scan system is about 15 dB larger, but on the other hand the wavelength resolution of the VCSEL based interrogator is 2.7 times higher. Note that the FBG spectra contain a sharp power drop-off at three of the twenty-two peaks. This is caused by the saturation due to an integration time which was set too high. These three peaks were not used in the analysis presented in the paper.

(a)

(b)