Optoelectronic oscillator-based interrogation system for Michelson interferometric sensors

Abstract

High-performance interrogation systems for optical fiber sensors are extensively required in applications of environmental condition monitoring. In this article, we propose and demonstrate a Michelson interferometer (MI) interrogation system based on optoelectronic oscillator (OEO). The frequency of the OEO is related to the free spectral range (FSR) of the MI. Thus, when the FSR of the MI varies with the change of the external physical factors, the frequency of the OEO would shift and can be used for interrogation. We demonstrate that the temperature sensitivity and interrogation resolution are 35.35 MHz/℃ and 0.012 ℃, respectively. Such OEO-based scheme enables wavelength-to-frequency mapping and promises the wide linear interrogation range, high-resolution and high-speed interrogation.