Conference paper
Experimental Study of Convex Coded Synthetic Transmit Aperture Imaging
Synthetic transmit aperture imaging is investigated using a convex array transducer. To increase the signal-to-noise ratio, a multi-element subaperture is used to emulate the spherical wave transmission, and the conventional short excitation pulse is replaced by a linear FM signal. The approach is compared to the conventional application of the convex array in commercial scanners.
The array used is a commercial 5.5 MHz, 128 element array with 60% bandwidth and λ pitch. For conventional imaging a 64 element transmit aperture is used with a 2 cycle temporally weighted sinusoid as excitation signal. For synthetic aperture imaging an 11 element transmit aperture is used with a 20 μs linear FM signal as excitation.
For both methods, 128 elements are used on receive. Measurements are done using our experimental multi-channel ultrasound scanner, RASMUS. Wire phantom measurements show an improvement in lateral resolution of about 30% throughout the image with lower near and far field sidelobe levels. Results from a cyst phantom show big improvements in contrast resolution, and an increase in penetration depth of about 2 cm.
In-vivo images of the abdomen of a healthy 27 year old male show slight improvements in image quality, especially in the near field.
Language: | English |
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Publisher: | IEEE |
Year: | 2002 |
Pages: | 1573-1576 |
Proceedings: | 2002 IEEE Ultrasonics Symposium |
ISBN: | 0780375823 and 9780780375826 |
ISSN: | 15513025 and 10510117 |
Types: | Conference paper |
DOI: | 10.1109/ULTSYM.2002.1192603 |
ORCIDs: | Jensen, Jørgen Arendt |
20 mus 5.5 MHz Apertures Bandwidth Image resolution Imaging phantoms RASMUS Signal resolution Signal to noise ratio Transducers Ultrasonic imaging Ultrasonic variables measurement Wire biomedical ultrasonics contrast resolution convex array transducer convex coded synthetic transmit aperture imaging cyst phantom far field sidelobe levels image quality linear FM signal multi-channel ultrasound scanner multi-element subaperture penetration depth spherical wave transmission temporally weighted sinusoid ultrasonic imaging ultrasonic transducer arrays wire phantom measurements