Title :
A new technique for adaptive imaging in the presence of distributed aberrations
Author :
Ng, Gary C. ; Freiburge, Paul D. ; Walker, William F. ; Trahey, Greg E.
Author_Institution :
Dept. of Biomed. Eng., Duke Univ., Durham, NC, USA
Abstract :
Acoustic velocity inhomogeneities in tissue result in aberration of ultrasonic images. These aberrations can be modeled as a near field thin phase screen or as a distributed aberrator. Current techniques for the correction of distributed aberrators are limited to application on point targets. A new technique is proposed using multiple transmits from spatially shifted transmit apertures, called translating transmit apertures, which can remove the decorrelation of speckle with receiver position. Translating transmit apertures, when used in conjunction with phase conjugate filters, can correct for distributed aberrations in the presence of speckle targets
Keywords :
adaptive signal processing; biomedical ultrasonics; medical signal processing; speckle; ultrasonic velocity; adaptive imaging technique; distributed aberrations; distributed aberrator; medical diagnostic imaging; near field thin phase screen; phase conjugate filters; point targets; spatially shifted transmit apertures; speckle decorrelation; speckle targets; tissue acoustic velocity inhomogeneities; translating transmit apertures; ultrasonic images aberration; Acoustic distortion; Acoustic propagation; Acoustic pulses; Acoustic transducers; Bandwidth; Degradation; Delay effects; Frequency estimation; Speckle; Ultrasonic imaging;
Conference_Titel :
Ultrasonics Symposium, 1995. Proceedings., 1995 IEEE
Conference_Location :
Seattle, WA
Print_ISBN :
0-7803-2940-6
DOI :
10.1109/ULTSYM.1995.495830