Low-noise electroencephalogram acquisition system based on active electrode

The invention discloses a low-noise electroencephalogram acquisition system based on an active electrode, and relates to the technical field of brain-computer interfaces, the low-noise electroencephalogram acquisition system comprises an active electrode, an electroencephalogram acquisition module and an upper computer, an anti-aliasing filter circuit and a switch chopping modulator are integrated in the active electrode, the electroencephalogram acquisition module comprises a multi-stage parallel noise reduction circuit, a fully differential instrumentation amplifier, an analog-to-digital converter and a single chip microcomputer which are cascaded in sequence; in each electroencephalogram signal acquisition period T, the switch chopping modulator acquires the electroencephalogram signal after anti-aliasing filtering processing in a chopping switch closing time period and modulates the electroencephalogram signal to a higher frequency band, and acquires a noise signal in the circuit in a chopping switch open