ONION Method: A Panel Measurement Method Based on Least Squares Fitting toExperimental Waveforms

摘要

The ONION method is a signal extrapolation procedure designed for use withtransient reflected and transmitted waveforms acquired during a panel test. Sound speeds and losses for each panel layer are deduced by least squares fitting of model waveforms to measured waveforms at each temperature, pressure, and frequency of interest. At present, the method can accommodate both reflected and transmitted-wave data at normal incidence interrogation, or reflected-wave-only