A Gaussian framework for modeling effects of frequency-dependent attenuation, frequency-dependent scattering, and gating.

Keith A Wear

doi:10.1109/tuffc.2002.1049739

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A Gaussian framework for modeling effects of frequency-dependent attenuation, frequency-dependent scattering, and gating.

Keith A Wear

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Abstract

For a wide range of applications in medical ultrasound, power spectra of received signals are approximately Gaussian. It has been established previously that an ultrasound beam with a Gaussian spectrum propagating through a medium with linear attenuation remains Gaussian. In this paper, Gaussian transformations are derived to model the effects of scattering (according to a power law, as is commonly applicable in soft tissues, especially over limited frequency ranges) and gating (with a Hamming window, a commonly used gate function). These approximations are shown to be quite accurate even for relatively broad band systems with fractional bandwidths approaching 100%. The theory is validated by experiments in phantoms consisting of glass particles suspended in agar.

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Agar Artifacts Computer Simulation Glass Image Enhancement Linear Models Models, Biological Models, Statistical Normal Distribution Phantoms, Imaging Quality Control Scattering, Radiation Signal Processing, Computer-Assisted Ultrasonography Comparative Study Journal Article Research Support, U.S. Gov't, P.H.S.Validation Study

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Keith A Wear. 2002. A Gaussian framework for modeling effects of frequency-dependent attenuation, frequency-dependent scattering, and gating.. https://doi.org/10.1109/tuffc.2002.1049739

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