IMPEDANCE TYPE BREATH MEASUREMENT SYSTEM

摘要

Disclosed is an impedance type breath measurement system, comprising: a breath carrier signal acquisition module used for acquiring a breath carrier signal; a demodulation filter circuit module used for demodulating and filtering the breath carrier signal to obtain a breath waveform signal; an amplification circuit module used for amplifying an alternating-current component in the breath waveform signal to obtain an amplified waveform signal; a waveform baseline adjustment circuit module used for adjusting the state of the amplification circuit module in real time to be an unsaturated amplification state; a high-pass filter circuit module used for filtering out a direct-current signal in the amplified waveform signal to obtain a first analogue waveform signal; an analogue-to-digital conversion circuit module used for conducting analogue-to-digital conversion on the first analogue waveform signal to obtain a first digital waveform signal; and a microcontroller processing module used for conducting digital signal processing on the first digital waveform signal to obtain a breath measurement result. By means of the embodiment of the present invention, a waveform baseline can be recovered quickly, so that a displayed waveform has higher stability.