Interrogation of extrinsic Fabry-Perot interferometric sensors using arrayed waveguide grating devices

In this paper we present details of a solid state interrogation system based on a 16-channel Arrayed Waveguide Grating (AWG) for interrogation of Extrinsic Fabry-Perot Interferometric (EFPI) sensors. The sensing element is configured In a reflecting mode and is illuminated by a broad-band light source through art optical fiber. The spectrum of fight reflected from the sensor is analyzed using an AWG device acting as a coarse spectrometer. Using measurement points from the AWG channels, the original spectrum of the sensing element is reconstructed by a means of curve fitting. This allows sufficient it(formation for the position of the reflection peak (or inverted peak) to be uniquely determined and the value of a measurement quantity obtained. In addition to the theoretical simulations of the proposed measurement system, we provide details of the laboratory evaluation