北京市测震台网数字地震台站台基背景噪声分析

基于北京市测震台网连续三分量地震计波形数据，计算28个测震台站台基噪声，利用Welch方法计算噪声功率谱密度（PSD），进而计算地震台台基1-20 Hz地动噪声均方根值（RMS）和观测动态范围。结果表明，依照《地震台站观测环境技术要求》，北京市测震台网中有11个Ⅰ类台、9个Ⅱ类台、6个Ⅲ类台、2个Ⅳ类台。通过分析北京市测震台网数字地震台背景噪声水平，为测震台网的规划建设提供数据支持。

Analysis on station background noise of digital seismic stations of Beijing Seismic Network

In this paper, basing the continuous waveform data of three-component seismometers of Beijing Seismic Network, the station base noise of 28 digital seismic stations in Beijing has been calculated, where the Welch method is used to calculate the noise power spectral density (PSD). And then the PSD is used to calculate the root mean square (RMS) and the observed dynamic range of the 1-20 Hz ground motion noise of the seismic platform. The results show that there are 11 stations of ClassⅠ, 9 stations of ClassⅡ, 6 stations of ClassⅢ and 2 stations of ClassⅣ according to "Technical Requirements for Observation Environment of Seismic Stations". It provides data support for the planning and construction of Beijing Seismic Network by analyzing the background noise level of the digital seismic stations.