| Autor: |
Keravnou CP; Department of Mechanical and Manufacturing Engineering, University of Cyprus, 75 Kallipoleos, 1678 Nicosia, Cyprus., Averkiou MA; Department of Mechanical and Manufacturing Engineering, University of Cyprus, 75 Kallipoleos, 1678 Nicosia, Cyprus. |
| Jazyk: |
angličtina |
| Zdroj: |
The Journal of the Acoustical Society of America [J Acoust Soc Am] 2014 May; Vol. 135 (5), pp. 2545-52. |
| DOI: |
10.1121/1.4871356 |
| Abstrakt: |
Nonlinear imaging was implemented in commercial ultrasound systems over the last 15 years offering major advantages in many clinical applications. In this work, pulsing schemes coupled with a dual frequency pulse are presented. The pulsing schemes considered were pulse inversion, power modulation, and power modulated pulse inversion. The pulse contains a fundamental frequency f and a specified amount of its second harmonic 2f. The advantages and limitations of this method were evaluated with both acoustic measurements of harmonic generation and theoretical simulations based on the KZK equation. The use of two frequencies in a pulse results in the generation of the sum and difference frequency components in addition to the other harmonic components. While with single frequency pulses, only power modulation and power modulated pulse inversion contained odd harmonic components, with the dual frequency pulse, pulse inversion now also contains odd harmonic components. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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