An EEG Acquisition System

Abstract

The present invention relates to an EEG acquisition system, comprising an EMC protection circuit (100), used for receiving physiological signals on the surface of the forehead of a human body in real time, and converting the physiological signals into current signals; an instrument amplifier, used for receiving the processed EMC protection circuit the current signal, and amplify the current signal; the signal amplification circuit (200), is used to receive the current signal amplified by the instrumentation amplifier, and amplify the current signal again, so that the signal-to-noise ratio is further improved; AC coupling The circuit (300) is used to receive the re-amplified current signal, perform high-pass filtering and then couple to the instrument amplifier to form a coupling loop with high-pass filtering function. The invention enhances the stability of EEG signal acquisition, reduces the overall noise level, and greatly improves the signal-to-noise ratio of the overall acquisition circuit.

Description

technical field [0001] The invention relates to the collection of electroencephalogram physiological signals, which are used for extracting physiological electric signals on the forehead surface of a human body, in particular to an electroencephalogram acquisition system. Background technique [0002] At present, the acquisition of EEG vital signals worldwide is facing various technical challenges, mainly because EEG physiological signals are extremely weak signals and are easily affected by many external factors. The traditional EEG acquisition circuit structure is mostly implemented by conventional instrumentation amplifiers and multi-stage amplifier circuits. The circuit structure is complex, the overall signal-to-noise ratio is not high, and it is easily affected by factors such as baseline drift and high noise, and its stability is poor. The signal quality of the EEG physiological signal collection is poor, which brings great challenges and difficulties to the subsequen...

AI Technical Summary

Problems solved by technology

[0004] At present, most of the instruments on the market use instrumentation amplifiers with various amplifiers for multi-stage amplification to complete the acquisition of EEG physiological signals. The stability and signal-to-noise ratio are poor, and the anti-EMC ability is weak. Most of them can only be used for scientific research experiments and clinical applications. Poor use

At the same time, integrated chips are also used to complete EEG acquisition, mainly using the ADS129x series chips of American TI Company. This type of chip can complete multi-channel EEG signal acquisition and has a simple structure, but there are still many problems in the acquisition of EEG physiological signals.

[0005] Some of these integrated chips are only suitable for collecting electrophysiological signals. When collecting electrophysiological signals, the common mode rejection ratio and electrical noise cannot meet the actual requirements.

The EEG acquisition integrated chip launched by TI can only be used for EEG signal acquisition, and at the same time, there will be problems such as poor anti-EMC effect, baseline drift, and poor low-frequency stability.

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