Conference paper
Multi element synthetic aperture transmission using a frequency division approach
In synthetic aperture imaging an image is created by a number of single element defocused emissions. A low resolution image is created after every emission and a high resolution image is formed when the entire aperture has been covered. Since only one element is used at a time the energy transmitted into the tissue is low.
This paper describes a novel method in which the available spectrum is divided into 2N overlapping subbands. This will assure a smooth broadband high resolution spectrum when combined. The signals are grouped into two subsets in which all signals are fully orthogonal. The transmitting elements are excited so that N virtual sources are formed.
All sources are excited using one subset at a time. The signals can be separated by matched filtration, and the corresponding information is extracted. The individual source information is hence available in every emission and the method can therefore be used for flow imaging, unlike with Hadamard and Golay coding.
The frequency division approach increases the SNR by a factor of N2 compared to conventional pulsed synthetic aperture imaging, provided that N transmission centers are used. Simulations and phantom measurements are presented to verify the method.
Language: | English |
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Publisher: | IEEE |
Year: | 2003 |
Pages: | 1942-1946 |
Proceedings: | 2003 IEEE Ultrasonics Symposium |
ISBN: | 0780379225 and 9780780379220 |
Types: | Conference paper |
DOI: | 10.1109/ULTSYM.2003.1293297 |
ORCIDs: | Jensen, Jørgen Arendt |
Apertures Data mining Energy resolution Error correction Error correction codes Filtration Frequency conversion Golay coding Hadamard coding High-resolution imaging Image resolution Signal resolution acoustic imaging acoustic signal processing beamforming biological tissue biomedical ultrasonics broadband flow imaging frequency dividers frequency division approach high resolution spectrum matched filtration orthogonal signals phantom measurements pulsed synthetic aperture imaging signal-to-noise ratio single element defocused emissions source information synthetic aperture transmission transmitted energy transmitting elements ultrasonic transmission virtual sources