SMAG2000:一体化GNSS强震仪及其地震监测性能分析

SMAG2000: Integrated GNSS Strong Seismograph and Analysis of Its Seismic Monitoring Performance

地震监测可以帮助人们了解地震形成的机制,对地震预警也有着重要意义。结合加速度计和全球导航卫星系统(global navigation satellite system,GNSS)高精度数据处理方法,利用嵌入式开发技术,研制了一体化GNSS强震仪SMAG2000用于实时地震监测。该仪器具有以下特点:(1)将GNSS与加速度计数据融合,仪器没有量程限制,并可以获得永久位移。(2)通过振动台测试,对不同频率的正弦波和模拟的地震波信号,仪器测量的结果与参考值残差的标准差优于0.4 cm,相关系数大于0.99。(3)所使用的核心组件与配件均为国产,成本可控,可以在中国地震监测网实施布设,实现地震台网和大地测量台网的深度融合,响应《国家地震科技创新工程》。

Objectives:Earthquake monitoring can help us comprehend the formation of the earthquake, and it’s also important for earthquake early warning.However,there are three main problems when using traditional seismometers to monitor crustal deformation.(1)The seismometer is seriously affected by low-frequency noise and baseline error,and the displacement result generated by its integration will diverge.(2) The seismometer has a limited measuring range.(3) The seismometer cannot observe the permanent crustal deformation.Methods:To solve the above problems, we combined accelerometers and global navigation satellite system(GNSS) high-precision data-processing methods using embedded technology and developed an integrated GNSS strong seismograph SMAG2000 for real-time seismic monitoring. The SMAG2000 consists of the accelerometer, GNSS board, and embedded development board. The algorithms of real-time precise point positioning and data fusion are operated in the SMAG2000. We conducted the shaker table test to evaluate the performance of the SMAG2000.The shake table simulated different vibrations and output the reference displacement and acceleration. The experiment tested the performance of the SMAG2000under the stationary state, sinusoidal vibration, and simulated seismic wave vibration, respectively. Results: Firstly,The standard deviations of the noise were 0.57 cm/s2 and 0.84 cm for acceleration and displacement,respectively.Secondly, the standard deviation of the difference between the results and reference for the sine wave was better than 0.4 cm, and the correlation coefficient was better than 0.99. Finally, the standard deviation and correlation coefficient of seismic waves are 0.293 cm and 0.986 for strong earthquakes. Those were 0.360 cm and 0.951 for weak earthquakes. Conclusions: The result implies that SMAG2000 can monitor seismic displacement and deformation in real-time mode. Moreover, the SMAG2000 uses domestic parts and has the advantages of low cost, small size, and low power consumption. The instrument has no range limit and can obtain permanent displacement. Thus, the SMAG2000 has great development potential and market prospects for seismic monitoring research.