EEG acquisition system based on active electrodes with common-mode interference suppression by Driving Right Leg...

Area of Science:

• Biomedical Engineering
• Neuroscience
• Signal Processing

Background:

• High-quality electroencephalography (EEG) signal acquisition is crucial for various applications, including brain-computer interfaces and home healthcare.
• Traditional EEG systems often suffer from noise and interference, limiting their effectiveness in non-clinical settings.
• Active electrodes and advanced circuit designs are needed to overcome these limitations.

Purpose of the Study:

• To develop and present a novel system for EEG signal acquisition.
• To demonstrate the system's capability for high-fidelity signal capture with reduced interference.
• To evaluate the system's suitability for portable and non-clinical use.

Main Methods:

• The system utilizes active electrodes integrated with a Driving Right Leg (DgRL) circuit for single-ended amplification and analog-to-digital conversion.
• The DgRL circuit ensures a common mode rejection ratio exceeding 110 dB, significantly reducing network interference.
• The front-end amplification is integrated at the electrode level, minimizing sensitivity to contact quality and cable movement.

Main Results:

• The system achieves high-quality EEG signal acquisition with minimal network interference for both wet and dry electrodes.
• Integrated noise in the 0.5–100 Hz band is between 0.62 and 1.3 μV, depending on the configuration.
• The system demonstrates low power consumption (390 μA per channel for amplification and A/D conversion).

Conclusions:

• The developed EEG acquisition system offers low noise and high interference suppression.
• Its quick setup and portability make it suitable for applications outside clinical environments, such as home care and brain-computer interfaces.
• The system enables reliable EEG monitoring in consumer-oriented applications and wearable devices.