The application provides a kind of adaptive
gain noise reduction control method and
system based on balance
detector, it is related to automatic
noise reduction technical field.The method comprises first obtaining the original differential current output by balance
detector, obtains the amplified current with
noise after being amplified by back-end hardware
gain, and determines compensation current data.Subsequently, the fluctuation amplitude of amplified current is monitored in real time, and when the fluctuation amplitude exceeds the preset wake-up threshold, the
noise reduction process is started: control output compensation current, couple and superimpose it with amplified current to obtain mixed
signal; the digital mixed
signal is obtained by analog-
digital conversion to the mixed
signal, and then the preset multi-
modal digital filter is used to decouple it, to generate the corresponding virtual
reference noise signal in the digital domain, and finally the digital mixed signal and the virtual
reference noise signal are digitally subtracted, to obtain the high signal-to-noise ratio
target signal.This realizes the cooperative control of
gain amplification and
noise reduction, solves the problem of bottom noise lifting accompanied by high gain, and improves the signal-to-noise ratio.