Abstract

Multiplexed wavelength shift detectors are increasingly used to read out arrays of fiber Bragg grating (FBG) sensors that are illuminated by amplified spontaneous emission sources. The fundamental sensitivity limit of these systems is due to excess noise from the light source. This limit is evident when optical intensity is high enough to overcome the electronic noise of the measurement system. Here, we derive a formula for the fundamental sensitivity limit and show it is only a function of sensor optical bandwidth. The formula is corroborated by experiment by measuring the wavelength noise of 12 FBG sensors as a function of optical intensity. First, the expected noise vs. intensity is calculated from the formula with known sensor optical bandwidths and shown to agree to the measured results without fit. Then, the formula is fit to the experimental data, with optical bandwidth as a parameter, to extract the optical bandwidth of each FBG from the noise saturation behavior with respect to optical intensity.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.