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Phase aberration correction for ultrasound imaging in temporal-spatial frequency domain

Phase aberration due to tissues with inhomogeneous acoustic speeds is a major source for image degradation in medical ultrasound. In most phased array pulse-echo ultrasound systems, the delay used to steer and focus the beams are calculated assuming constant speed. In practice, however, the acoustic speed varies for different types of tissue. We present a method of estimating the phase errors between the elements of a linear array, based on signal representation in the spatial-temporal Fourier domain. Compared to the standard cross-correlation methods used for time delay estimation, the proposed technique shows better performance.