DocumentCode :
1072792
Title :
Analysis and correction of ultrasonic wavefront distortion based on a multilayer phase-screen model
Author :
Huang, Deng-Huei ; Tsao, Jenho
Author_Institution :
Graduate Inst. of Commun. Eng., Nat. Taiwan Univ., Taipei, Taiwan
Volume :
49
Issue :
12
fYear :
2002
Firstpage :
1686
Lastpage :
1703
Abstract :
A model is introduced that incorporates the cumulative wavefront distortion effects caused by spatial heterogeneities along the path of propagation, and a corresponding model-based wavefront distortion-correction method is presented. In the proposed model, a distributed heterogeneous medium is lumped into a series of parallel phase screens. The distortion effects can be compensated-without a priori knowledge of the distorting structure-by backpropagation of received wavefronts through hypothetical multiple phase screens located between the imaging system and targets, while each pointwise time shift is adjusted iteratively to maximize a specified image quality factor at the final layer. Theoretical analyses indicate that the mean speckle brightness decreases monotonically with the root-mean-square value of distributed phase distortions; therefore, the speckle brightness can be used as an image quality factor. Experimental one-dimensional (1-D) array data with simulated distortion effects based on a real 2-D abdominal-tissue map were used to evaluate the performance of the proposed method and existing aberration-correction techniques. The simulated characteristics of wavefront distortion and relative performance of existing correction techniques were similar to reports based on abdominal-wall data and breast data. This investigation shows that the proposed method provides better compensation for wavefront distortion.
Keywords :
Q-factor; acoustic distortion; biomedical ultrasonics; compensation; speckle; ultrasonic imaging; 2D abdominal tissue map; US wavefront distortion correction; backpropagation; cumulative wavefront distortion effects; distributed phase distortions; image quality factor; imaging system; mean speckle brightness; multilayer phase-screen model; parallel phase screens; propagation path spatial heterogeneities; Abdomen; Apertures; Backpropagation; Breast; Brightness; Image analysis; Image quality; Nonhomogeneous media; Phase distortion; Speckle; Abdomen; Algorithms; Computer Simulation; Humans; Image Enhancement; Models, Biological; Quality Control; Scattering, Radiation; Sensitivity and Specificity; Ultrasonography; Ultrasonography, Mammary;
fLanguage :
English
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on
Publisher :
ieee
ISSN :
0885-3010
Type :
jour
DOI :
10.1109/TUFFC.2002.1159847
Filename :
1159847
Link To Document :
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