Tracking Based Baseline Restoration for Acquisition of Impedance Cardiogram and Other Biosignals

Most of the biosignals have a baseline which may drift over a large range compared to the excursion of the signal of interest. To make effective use of the input dynamic range of the signal acquisition setup, this offset drift needs to be cancelled. The circuit reported here uses amplitude tracking technique for estimation and removal of the baseline drift. This circuit is independent of the processor to which the signal acquisition unit is interfaced