Kendall R Farnham, Ethan K Murphy, Ryan J Halter
This paper describes the design of a small form-factor, low-cost, portable electrical impedance tomography (EIT) system with a custom analog front end and field-programmable gate array (FPGA) controller. Detailed analog and digital design choices are presented and discussed in the context of currently available state-of-the art hardware components and in relation to EIT-driven system requirements. The system is capable of acquisition speeds required for real-time imaging under appropriate acquisition configurations, provides high-SNR measurements over the 100 Hz to 1 MHz target bandwidth, and has customizable acquisition parameters to allow users to optimize the system for a wide variety of imaging applications. Hardware characterization results demonstrate competitive performance relative to existing small form-factor EIT systems, while multi-frequency imaging results demonstrate successful EIT image reconstruction across the evaluated frequency range. The development of this highly configurable, high-performing, portable EIT system provides a significant step toward expanding the practical use of multi-application, real-time EIT imaging.