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For breast cancer imaging, ultrasound computer tomography (USCT) is an emerging technology. To improve the image quality of our full 3-D system, a new transducer array system (TAS) design was previously proposed. This work presents a manufacturing approach which realises this new design. To monitor the transducer quality during production, the electro-mechanical impedance (EMI) was measured initially and after each assembly step. To evaluate the measured responses, an extended Krimholtz–Leedom–Matthaei (KLM) transducer model was used. The model aids in interpreting the measured responses and presents a useful tool for evaluating parasitic electric effects and attenuation at resonance. For quality control, the phase angle at thickness resonance φ t was found to be the most specific EMI property. It can be used to verify the functionality of the piezocomposites and allows reliable detection of faults in the acoustic backing. Evaluating the final response of 68 transducers showed 5% variance of the series resonance frequency. This indicates good consistency of derived ultrasound performance parameters.

As today's standard screening methods often fail to diagnose breast cancer before metastases have developed, an earlier breast cancer diagnosis is still a major challenge. To improve this situation, we are currently developing a fully three-dimensional ultrasound computer tomography (3D USCT) system, promising high-quality volume images of the breast. For obtaining these images, a time-consuming reconstruction has to be performed. As this is currently done on a PC, parallel processing in reconfigurable hardware could accelerate both signal and image processing. In this work, we investigated the suitability of an existing data acquisition (DAQ) system for further computation tasks. The reconfiguration features of the embedded FPGAs have been exploited to enhance the systems functionality. We have adapted the DAQ system to allow for bidirectional communication and to provide an overall process control. Our results show that the studied system can be applied for data processing.