Multipurpose low cost bio-daq system for real time biomedical applications

Bio-electric signals are all kinds of electrical signals that can be measured and monitored from biological beings. These signals are of low frequency and very low voltage and are often contaminated with surrounding noise. Hence the bioelectric signal acquisition system should provide very high input impedance, very high Common Mode Rejection ratio (CMRR), high voltage gain and high selectivity. To achieve these specifications, bio-electric acquisition systems are commonly designed using precision components. Use of precision components makes the design very expensive and occasionally availability constraints of these components in the local market, makes the design more difficult. The main objective of this work is to develop a compact and cost effective bio-electric signal acquisition system for real time biomedical applications. The proposed design employs general purpose electronic components which are commonly available in any electrical lab that makes the cost of prototype around $160. The system mainly consists of Op-Amp based bio-amplifier, data acquisition board and a laptop. Design examples are in the form of Electro Cardio Gram (ECG), Electro Myogram (EMG), Electroculogram (EOG) and Electro Encephalogram (EEG) acquisitions.