Title :
Influence of missing array elements on phase aberration correction for medical ultrasound
Author :
Karman, M. ; Köymen, Hayrettin ; Atalar, Abdullah ; O´Donnell, Matthew
Author_Institution :
Dept. of Electr. & Electron. Eng., Bilkent Univ., Ankara, Turkey
Abstract :
The influence of missing array elements on aberration correction based on time delay estimation using radio frequency signals of neighboring elements is experimentally investigated. Normalized cross correlation and sum of absolute differences are employed as the cost functions in aberration estimation. Their performance is tested through various measurements using radio frequency data acquired with a 3.3 MHz, 64-element phased array. Variation of cost functions and phase estimation error are obtained for different combinations of number of missing elements, amount of aberration, and noise level. For a particular combination of these parameters, a set of B-scan images is reconstructed and presented to examine the effects of residual phase errors on image quality.<>
Keywords :
aberrations; acoustic noise; antenna phased arrays; biomedical ultrasonics; correlation methods; measurement errors; 3.3 MHz; 64-element phased array; B-scan images; RF signal processing; aberration estimation; acoustic imaging; cost functions; image quality; image reconstruction; medical ultrasound; missing array elements; neighboring elements; noise level; normalized cross correlation; phase aberration correction; phase estimation error; radio frequency data; radio frequency signals; residual phase errors; sum of absolute differences; time delay estimation; Cost function; Delay effects; Delay estimation; Frequency estimation; Frequency measurement; Phase measurement; Phased arrays; RF signals; Radio frequency; Testing;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on
