Digitally Controlled Reference Impedance Device for Test and Calibration of the Bio-Impedance Measurement System (BIMS) in a Networked Environment
With emerging new developments in the scope of the Bio-Impedance Measurement System (BIMS), an automated test of the data acquisition equipment and its proper tuning in conditions of strict accuracy requirements have become a critical issue. Such BIMS, as the one designed by ELIKO Competence Centre and Artec Design LLC, is basically a complex synchronous data acquisition platform, with the base elements being a sine wave excitation signal generator, a multi-channel sampler and a DSP unit. Such a system requires full testing and calibration prior to conducting complicated and expensive biomedical experiments. Thus, the solution was selected, where the observable biological system is replaced with a digitally controlled resistance and capacitance array (DCRCA) during the testing and calibration process. DCRCA is the part of the proposed digitally controlled reference impedance device (DCRID), which emulates the behaviour of biological tissue in a determined manner. The parameter variation is supervised by a microcontroller, which enables to change properties of DCRCA with high resolution and exact timing.
KeywordsCapacitance Array Variable Resistor Float Control Reference Resistor Determined Manner
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