Power-law shot noise model for the ultrasound RF echo
نویسندگان
چکیده
We model the radio-frequency (RF) ultrasound echo by a shot noise process with narrow-band power-law lter function. As a consequence, the in-phase and quadrature components of the return signal are shown to exhibit 1=f type spectral behavior. The envelope also exhibits this type of spectral behavior but with a diierent exponent. The model parameters, namely the rate of the point process and the power-law exponent, are related to tissue density and at-tenuation, respectively. Since these tissue characteristics change due to disease, estimates of the model parameters are investigated as potential tissue characterization features. We validate our claims based on clinical ultrasound images.
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