Ultrasonic Array Characterization in Multiscattering and Attenuating Media Using Pin Targets

TL;DR

This study introduces a method for characterizing ultrasonic array performance in complex media using pin targets, employing advanced coding techniques to improve measurement accuracy in scattering and attenuating environments.

Contribution

The paper demonstrates the effectiveness of pin targets combined with coded signals for ultrasonic array characterization in challenging media, a novel approach in the field.

Findings

Pin targets are suitable for array characterization in scattering media.

Complementary Golay sequences improve signal detection under weak reflections.

The method accurately measures transfer function, resolution, and beam width in complex media.

Abstract

This paper presents an approach to characterize ultrasonic imaging arrays using pin targets in commercial test phantoms. We used a 128-element phased array transducer operating at 7.5 MHz with a fractional bandwidth of %70. We also used a tissue-mimicking phantom in the measurements. This phantom consists of pin targets with a 50-micrometer diameter. We excited the transducer with pulsed and coded signals. We used Complementary Golay Sequences to code the transmitted signal and Binary Phase Shift Keying for modulation. We characterized the transducer array using the transfer function, line spread function, range resolution, and beam width in an attenuating and scattering medium. We showed that the pin targets, which are very thin compared to the diffraction-limited focus of the transducer array, are suitable for the transducer characterization under weak reflected signal conditions.