On modeling biomedical ultrasound RF echoes using a power-law shot-noise model

We propose a new model for the RF ultrasound echo, namely the power-law sho t-noise process. Based on this model, the in-phase and quadrature component s of the echo are shown to exhibit 1/f(beta)-type spectral behavior, in a s ense that is defined in the paper. The envelope also exhibits this type of spectral behavior, but with a different exponent. This result explains the experimental observations by other researchers of the power-law trend of th e RF echo spectrum. Although the shot-noise model has been used in the past for modeling the RF echo, this is the first time that a power-law impulse response filter is used and that the resulting 1/f(beta)-type spectral beha vior of the RF echo has been investigated. The model parameters are linked to tissue characteristics, such as scatterer density and attenuation; thus, they have the potential to be used as tissue characterization features. Th e validity of the proposed model is tested based on a database of 100 clini cal ultrasound images of the breast.