A Biosignal Instrumentation System Using Capacitive Coupling for Power and Signal Isolation

Abstract

Requirements for patient safety and a high interference rejection ratio in medical equipment create a demand for effective isolation devices. A system scale approach that uses capacitive coupling for power and signal isolation is presented. In addition, we describe the development of an instrumentation system prototype that applies microwaves for power exchange and bidirectional data transfer across the isolation barrier. The system consists of an isolated transducer unit, a central unit, and a single coaxial cable between the units. The isolation capacitance is as low as 1.6 pF, inclusive of the digital data transfer and power exchange up to 600 mW of isolated direct current (dc) power. The system is suitable for line-powered biopotential measurements and it is shown that reducing the isolation capacitance from 180 to 1.6 pF improves the power line rejection by 30 dB in a typical electrocardiogram (ECG) measurement setup.

Web Services Based Bio-signal System Leveraging Support Vector Machines

“…The amplitude of R and S wave 1 The ratio of the R-R interval and R-S interval 1 The ratio of the R-R interval and P-R interval 1 The distance of R and S wave 1 The EEG data in [23] is also tested in our system. The datasets are consisted of five sets denoted as Z, F and S. Each set contains 100 single-channel EEG segments with 23.6 sec duration.…”

“…Biosignal analyzing [1][2][3] is an important research field of digital signal processing (DSP) and data mining. Techniques such as digital and adaptive filtering, spectrum estimation, compression, time series processing, source separation and pattern classification are used to analyze the features and interrelations of bio-signals.…”

High power transfer density and high efficiency 100 MHz capacitive wireless power transfer system

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Capacitive power transfer for contactless charging

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