Two-Dimensional Frequency Domain Phase Aberration Correction
Phase aberration due to tissues with inhomogeneous acoustic speeds is a major source of image degradation in medical ultrasound. In most phased array pulse-echo ultrasound systems, the delays used to focus and steer the beams are calculated assuming constant acoustic speed. However, it is known that the acoustic speed varies for different types of tissue, resulting in defocusing, loss of resolution, and blurring of the image. The issue of phase aberration measurement and correction has been the focus of several research groups in recent years1,2,3. Many of the existing techniques correct for aberration by estimating the phase error profile and using the estimate to align the rf signals.
KeywordsRadar Refraction Ghost Acoustics Sonar
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