Title :
Fast beam shape computation and wave propagation via the Radon transform
Author :
Pitts, Todd A. ; Greenleaf, James F.
Author_Institution :
Mayo Clinic, Rochester, MN, USA
Abstract :
An M-dimensional (M⩾2) linear shift-invariant operator equation may be reduced to a set of decoupled (M-1)-dimensional equations via the Radon transform. This decoupling allows the solution of each reduced equation separately on different processors in parallel. The solution to the full M-dimensional equation is then recovered via an inverse Radon transform. This solution method is particularly well suited to computation of beam shape and wave propagation in a homogeneous medium. For beam shape computation, Huygens´ integration over a two-dimensional aperture is reduced to a set of one-dimensional integrations (the number of one-dimensional integrations is determined via Shannon sampling theory from the highest angular harmonic present in the aperture distribution). The method is applied to computation of a wide bandwidth pulse distribution from a semi-circular aperture with a center frequency of 2.25 MHz. The results are compared with the full two-dimensional surface integration. Discussion of the increase in computational speed and sampling considerations affecting the accuracy of the distributed one-dimensional computations are presented
Keywords :
Radon transforms; biomedical ultrasonics; ultrasonic propagation; M-dimensional linear shift-invariant operator equation; Shannon sampling theory; aperture distribution; beam shape computation; center frequency; decoupled (M-1)-dimensional equations set; distributed one-dimensional computations accuracy; homogeneous medium; one-dimensional integrations; semicircular aperture; two-dimensional surface integration; wide bandwidth pulse distribution; Apertures; Bandwidth; Distributed computing; Ear; Fourier transforms; Frequency; Integral equations; Kernel; Sampling methods; Shape;
Conference_Titel :
Ultrasonics Symposium, 1999. Proceedings. 1999 IEEE
Conference_Location :
Caesars Tahoe, NV
Print_ISBN :
0-7803-5722-1
DOI :
10.1109/ULTSYM.1999.849221