Despeckling Ultrasound Images with Decorrelated Compounding in the Spatial Frequency Domain
Speckle variance in ultrasound images limits the detection of low-contrast targets. Recently a decorrelated compounding method in synthetic transmit aperture ultrasound imaging (DC in STA) had been proposed to reduce speckle variance. This paper extended the decorrelated compounding method beyond STA to any radio-frequency ultrasound images. A spatial-frequency-domain compounding method was proposed by dividing the spectrum of ultrasound images into overlapped sub-domains to produce multiple sub-images for decorrelation and compounding. The proposed method was demonstrated to perform better than the conventional Delay-and-Sum method in numerical simulations, and experimental study. The proposed method can be considered as an improved version of Welch’s method.