Abstract：At present, the seismic stations need to use two sets of acquisition systems to monitor and record weak signals and large seismic signals. To address this problem, this paper proposes a data acquisition method that automatically switches acquisition modes. When monitoring weak signals under normal conditions, the acquisition system uses small-signal channel ADCs for graded sampling, and when large earthquakes and giant earthquakes occur, the system automatically switches to use large-signal channel ADCs for sampling. Experiments show that the dynamic range of the acquisition system reaches 128 dB for single AD data acquisition at 100 Hz sampling, and 158 dB for double AD data acquisition at 100 Hz sampling.The improved data acquisition method effectively improves the dynamic range of seismic signal acquisition, and improves the performance of the data acquisition system to a certain extent without increasing the hardware cost.
