A Gaussian framework for modeling effects of frequency-dependent attenuation, frequency-dependent scattering, and gating.
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.
Wear
Keith A
KA
U.S. Food and Drug Administration, Center for Devices and Radiological Health, Rockville, MD 20852, USA. kaw@cdrh.fda.gov
D000362:Agar; D016477:Artifacts; D003198:Computer Simulation; D005898:Glass; D007089:Image Enhancement / Q000379:methods; D016014:Linear Models; D008954:Models, Biological; D015233:Models, Statistical; D016011:Normal Distribution; D019047:Phantoms, Imaging; D011786:Quality Control; D012542:Scattering, Radiation; D012815:Signal Processing, Computer-Assisted; D014463:Ultrasonography / Q000379:methods*
D000362:Agar