Electrophysiological Data Processing Using a Dynamic Range Compressor Coupled to a Ten Bits A/D Convertion Port

Abstract

The paper presents a hardware solution of the in vivo electrophysiological signals processing, using a continuous data acquisition on PC. The originality of the paper comes from some blocks proposal, which selective amplify the bio signals. One of the major problems in the electrophysiological signals monitoring is the impossibility to record the weak signals from deep organs that are covered by noise or by strong cardiac or muscular signals. An automatic gain control block is used, so that the high power skin signals are less amplified than the low components. The analog processing block is based on a dynamic range compressor, containing the automatic gain control block. The following block is a clipper since to capture all the transitions that escape from the dynamic range compressor. At clipper output a low-pass filter is connected since to abruptly cut the high frequencies, like 50Hz, ECG. The data vector recording is performing by strong internal resources micro controller including ten bits A/D conversion port.