Design and time-domain analysis of a high-voltage impulsed test-bed for near-field thermoacoustic tomography

Abstract

We present numerical time-domain modeling and validation framework for impulse-driven near-field thermoacoustics imaging. It has been recently demonstrated that this new imaging approach comprises a viable alternative for high performance and low-cost imaging using the thermoacoustic phenomenon. Placement of the imaged object in a close vicinity (near field) of an antenna elements along with generation of ultrashort (nanosecond) duration high-voltage excitation impulses further provide high imaging resolution and ensure that sufficient level of electromagnetic energy reaches the object under investigation. In order to analyze the measured results and also provide a design and optimization framework, this work presents a full-wave computational electromagnetic framework which couples the near-field electromagnetic field to the acoustic signal generation. The numerical method comprises a finite integral time domain method (FITD) based on the industry standard CST 2010 software package. The results can be further utilized for normalization and quantification of the generated images.