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| Title:
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Angular spectrum approach for fast simulation of pulsed non-linear ultrasound fields |
| Type:
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Article in proceedingsArticle in proceedings |
| Participant(s):
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Technical University of Denmark
Forfatter:
Jensen, Henrik
BK Medical Aps
Technical University of Denmark
Email:
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| Abstract:
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The paper presents an Angular Spectrum Approach
(ASA) for simulating pulsed non-linear ultrasound fields. The
source of the ASA is generated by Field II, which can simulate
array transducers of any arbitrary geometry and focusing. The
non-linear ultrasound simulation program - Abersim, is used as
the reference. A linear array transducer with 64 active elements
is simulated by both Field II and Abersim. The excitation is
a 2-cycle sine wave with a frequency of 5 MHz. The second
harmonic field in the time domain is simulated using ASA.
Pulse inversion is used in the Abersim simulation to remove the
fundamental and keep the second harmonic field, since Abersim
simulates non-linear fields with all harmonic components. ASA
and Abersim are compared for the pulsed fundamental and
second harmonic fields in the time domain at depths of 30 mm,
40 mm (focal depth) and 60 mm. Full widths at -6 dB (FWHM)
are f0.97, 0.95g mm at the focal depth for the fundamental
fields for ASA and Abersim, and f0.56, 0.55g mm for the second
harmonic fields. Full widths at -12 dB are f1.27, 1.26g mm for
the fundamental fields for ASA and Abersim, and f0.77, 0.73g
mm for the second harmonic fields. The calculation time, for
the second harmonic fields, using ASA is 12 minutes and for
all harmonic fields using Abersim is 14 hours. Compared to
Abersim, the error of ASA for calculating the second harmonic
fields is 1.5% at -6 dB and 6.4% at -12 dB, and the calculation
time is reduced by a factor of 70. |
| Published:
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part of: Proceedings of the 2011 IEEE International Ultrasonics Symposium (ISBN: 978-1-4577-1251-7), pages: 1583-1586, 2011, IEEE, |
| DOI:
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| File(s):
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| Presented at:
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2011 IEEE International Ultrasonics Symposium, Orlando, FL |
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