甚宽频带地震计噪声与环境耦合研究

Coupling Relationship between Noise of a Very BroadSeismometer and the Environment

摘要:

首先以甚宽频带地震计为研究对象，分析垂直向的片簧系统理论模型，探讨气压变化对仪器的LP噪声影响；通过理论分析，得出垂直向的片簧系统受气压变化影响较大。根据片簧系统的理论模型，设计一种密封安装方法，通过实验探讨地震计噪声与环境耦合关系（气压、温度和底座变形的关系）。最后对实验数据进行功率谱噪声分析，结果显示抽真空后地震计三个分向的噪声均降低，其中在100 s处垂直向、东西和南北向分别降低了10 dB、5 dB和6 dB。

Abstract:

In this study, the theoretical model of the vertical leaf spring system for very broadband seismometers was analyzed, and the influence of pressure changes on the LP noise of the instrument is discussed. The theoretical analysis showed that the vertical leaf spring system is quite affected by pressure changes. Then, according to the theoretical model of the leaf spring system, a kind of sealing installation method was designed, and the coupling relationship between the noise and the environment (pressure, temperature, and the base deformation) is discussed through experiments. Finally, the power spectrum noise analysis results of the experimental data showed that, after vacuuming, the noise in the three branch directions of the seismometer was reduced, at 100 s, by 10 dB, 5 dB, and 6 dB in the vertical direction, east-west direction, and north-south direction, respectively.