Multichannel Multiple Signal Classification for dispersion curves extraction of ultrasonic guided waves

Abstract : Multichannel acquisition of ultrasonic guided waves can be used to extract dispersion curves, from the time-position domain $(t-x)$ to the frequency-wavenumber $(f-k)$, or frequency-velocity domain $(f-c)$. Accurate measurements are needed in order to be able to precisely characterize the specimen, by improving the extraction of low amplitude modes and enhance resolution. The proposed method is based on the MUltiple SIgnal Classification algorithm combined with a multi-emitter and multi-receiver acquisition. In this work, this method is applied on experimental data to extract dispersive information from multilayered bonded specimens.