Abstract: Seismic data acquisition is the basis of earthquake observation and research. A design scheme about seismic data acquisition system based on high-speed data acquisition card NI USB-4432 and LabVIEW platform is proposed, including front-end conditioning circuit based on OP07 and LM224N, and data real-time acquisition, display and analysis system based on USB-4432 and LabVIEW platform. An adaptive wavelet threshold de-noising algorithm is presented to further improve the quality of the signal, the algorithm can de-noise adaptively according to the intensity of the collected signal, improve the Signal-to Noise Ratio（SNR） of the signal. Practical tests show that, the system is stable and reliable.Compared with the traditional threshold de-noising algorithm, the new algorithm can effectively improve the SNR. The experimental results show that the designed system has excellent de-noising performance and possesses a higher applied value.

Key words: wavelet threshold de-noising, seismic data acquisition, LabVIEW

摘要： 地震数据采集是地震观测与研究的基础。提出一种基于NI高精度数据采集卡USB-4432和LabVIEW的地震数据采集系统设计方案，包括基于OP07和LM224N的前端调理电路，基于USB-4432和LabVIEW的实时采集与分析系统。为进一步提升采集信号质量，提出一种自适应小波阈值去噪算法，该算法能根据采集信号强度自适应去噪，提高采集信号信噪比（Signal-to-Noise Ratio，SNR）。实验表明，系统稳定可靠，相比传统小波阈值去噪算法，新算法能显著提高SNR。实验结果表明，系统去噪性能优良，应用价值较强。

关键词: 小波阈值去噪, 地震数据采集, LabVIEW