Spectral eigendecomposition-based algorithm for cavity estimation in fibre-optic Fabry-P??rot pressure sensors

A novel signal processing-based approach for the real-time estimation of air-gap length in fibre optic extrinsic Fabry-P??rot pressure sensors is presented; the algorithm is based on eigendecomposition of the spectrum mutual correlation matrix. A pressure accuracy of 6.1 Pa (0.045 mmHg) is achieved in a pressure probe with 1.13 nm/kPa sensitivity, highlighting a 6.4 times improvement over standard quadrature point amplitude tracking by just acting on signal processing.