Patent ID: 9513372
Filing Date: 2016-12-06
CPC Classification: G01N,G01S,G01V,G06F

Claim Text:
1. A method to image a formation by automatically characterizing an echo contained in an ultrasonic signal, the ultrasonic signal being generated with an ultrasonic transducer, the method comprising: a. receiving data corresponding to the ultrasonic signal with the ultrasonic transducer of a downhole acoustic tool; b. calculating an energy ratio of the ultrasonic signal and localizing the echo contained in the ultrasonic signal using the energy ratio; comprising;  where Ex is energy at a given data point, a  is signal energy,  is noise energy and E c. windowing a portion of the ultrasonic signal around the localized echo; d. calculating a Fast Fourier Transform (FFT) and a Hilbert envelop of the windowed portion of the ultrasonic signal; e. estimating M echo parameter vectors from the FFT and the Hilbert envelope of the windowed portion of the ultrasonic signal, wherein each of the M echo parameter vectors comprises a plurality of echo parameters; f. calculating M parametric echo models based on each of the M echo parameter vectors; and g. iteratively minimizing a difference between the windowed portion of the ultrasonic signal and a sum of the M parametric echo models; transmitting parameters from the M parametric echo models for use in characterizing the formation.