A Modified Synthetic Aperture Focussing Technique Utilising the Spatial Impulse Response of the Ultrasound Transducer
نویسندگان
چکیده
In B-mode imaging, lateral resolution is impeded by the size and shape of the ultrasound beam used to create the image. For improved lateral resolution, a focussing method that utilises a beam model calculated using the Fraunhofer far field approximations to enhance the Synthetic Aperture Focussing Technique (SAFT) is proposed. The Beam Model Weighted Synthetic Aperture Focussing Technique (BMW-SAFT) method uses an approximation of the beam model to weight the focussing algorithm and adjust the aperture size based on distance from the transducer. Through application to simulated data the method is compared with the conventional SAFT, where the proposed algorithm is found to provide significant improvements over the conventional SAFT methods.
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