# SYNTHESIS OF DRIVING SIGNALS FOR MEDICAL IMAGING ANNULAR ARRAYS FROM ULTRASONIC X-WAVE SOLUTIONS

### l. Castellanos, A. Ramos, H. Calás

#### Abstract

An interesting approach for achieving high-resolution in ultrasonic imaging, is producing in real time limited diffraction waves with annular arrays; this potential option was presented by J.-Y. Lu in 1991 for collimating ultrasonic beams in medical imaging, approximating classical X waves with a finite aperture 10-annuli array, driven with 0-order X-wave excitation signal generated by solving the isotropic/homogeneous scalar wave equation. However, detailed solutions for a proper array electrical driving in order to form X-wave fields of both pressure and velocity potential have been not still reported. Paper objective is to show a tool to obtain approximated solutions for the inverse problems (aspect by-passed in classical approach) of synthesizing voltage excitations sets for producing both possible X wave field profiles, and comparatively investigate their distinct beam collimating capacities. All calculations, simulations and analyses were made for an ad-hoc developed 8-rings 2.5 MHz array transducer. Results show field distributions in ultrasonic pressure, created for two driving approaches derived by our inverse processing from calculated pressure and velocity potential fields. The good performances resulting in both cases for beam collimation, confirm the tool applicability. Results suggest the viability of our procedure as a promising alternative to classical X-wave driving calculations.

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#### Paper Citation

#### in Harvard Style

Castellanos L., Ramos A. and Calás H. (2010). **SYNTHESIS OF DRIVING SIGNALS FOR MEDICAL IMAGING ANNULAR ARRAYS FROM ULTRASONIC X-WAVE SOLUTIONS** . In *Proceedings of the Third International Conference on Bio-inspired Systems and Signal Processing - Volume 1: BIOSIGNALS, (BIOSTEC 2010)* ISBN 978-989-674-018-4, pages 290-295. DOI: 10.5220/0002746802900295

#### in Bibtex Style

@conference{biosignals10,

author={l. Castellanos and A. Ramos and H. Calás},

title={SYNTHESIS OF DRIVING SIGNALS FOR MEDICAL IMAGING ANNULAR ARRAYS FROM ULTRASONIC X-WAVE SOLUTIONS},

booktitle={Proceedings of the Third International Conference on Bio-inspired Systems and Signal Processing - Volume 1: BIOSIGNALS, (BIOSTEC 2010)},

year={2010},

pages={290-295},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0002746802900295},

isbn={978-989-674-018-4},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the Third International Conference on Bio-inspired Systems and Signal Processing - Volume 1: BIOSIGNALS, (BIOSTEC 2010)

TI - SYNTHESIS OF DRIVING SIGNALS FOR MEDICAL IMAGING ANNULAR ARRAYS FROM ULTRASONIC X-WAVE SOLUTIONS

SN - 978-989-674-018-4

AU - Castellanos L.

AU - Ramos A.

AU - Calás H.

PY - 2010

SP - 290

EP - 295

DO - 10.5220/0002746802900295