Patent Document ID: 8834376
Application ID: 13407378
Patent Flag: 1

Claim One:
1. A method of classifying a medium comprising: a) placing a transmitting transducer and a receiving transducer on opposite sides of a medium and traversing the medium with a plurality of frequency modulated ultrasound pulses between the transducers, each pulse being transmitted at a different frequency; b) identifying, with a computer, a signal from one of the ultrasound pulses received by the receiving transducer by pulse duration, center frequency and bandwidth; c) estimating propagation time through the medium for said signal using cross correlation with a replica of the transmitted pulse using the computer; d) improving the estimate of the propagation time by determining when the phase of said signal changes sign by performing an interpolation based on a linear portion of the phase using the computer; e) repeating steps (b)-(d) for each frequency of the plurality of ultrasound pulses; f) using information derived from the plurality of ultrasound pulses to generate a dispersion pattern of the medium using the computer; and g) using the computer to classify the medium based on characteristics of the dispersion pattern.