Year: 2008
Type: article
Abstract: Electrical impedance tomography (EIT) has many potential applications in medicine. The sensitivity and spatial resolution of EIT can be enhanced significantly by increasing the measurement signal-to-noise ratio (SNR), to which a significant contribution is made by the SNR of the current excitation sub-system. In this paper we present a prototype EIT current excitation sub-system with 80 dB SNR, exploiting both digital and analogue techniques. It uses digital waveform synthesis, a 16-bit DAC and subsequent reconstruction filter, to drive an enhanced Howland current source. Detailed analysis and testing of the current sub-system are presented. Its output impedance is 10 MOmega for different load impedances, varying slowly over the frequency range from 10 kHz up to 4 MHz.
Source: Physiological Measurement
Authors: M Rafiei-Naeini, H McCann
Institution: University of Manchester
Language: Spanish
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: bronze
Funder: Wellcome Trust
OpenAlex ID: W2059644152