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

  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 SMAG2000 under 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.