实时GNSS地震仪系统实现及精度分析

Real-time GNSS seismometer and its accuracy

高频GNSS数据实时精密单点定位(RTPPP)可实时获得地表瞬时动态形变和地震波信号,为地震参数快速确定、地震快速响应及海啸预警提供实时的观测资料.本文构建了实时GNSS地震仪系统,主要包括RTPPP和实时探测两部分.利用RTPPP方法处理了模拟的震动实验平台实验数据和2010年Baja California地震的数据,并与惯导(IMU)、事后PPP和差分相对定位结果比较,定量评估了实时GNSS地震仪系统的精度.结果表明,该系统可实现水平方向优于1cm,高程方向优于3cm的实时定位,且对Baja California地震的实时探测结果与南加州地震数据中心公布的结果相一致.

Real-time high-rate GNSS data can be used to obtain the dynamic ground displacements caused by earthquakes. The displacements are greatly useful in earthquake early warning and emergency response. A real-time GNSS seismometer system is built with real-time precise point positioning （RTPPP） and displacement waveforms detection techniques. In order to evaluate the accuracy of real-time displacement waveforms derived from RTPPP, simulated data from a shaking table platform, which can generate the dynamic displacements, and real-world data of the 2010 Baja California earthquake are processed. Comparing the above results with those of Inertial Measurement Unit （IMU）, precise point positioning （PPP） and relative positioning, it is illustrated that the real-time GNSS seismometer system is able to obtain the displacement waveforms with the accuracy of better than 1 cm and 3 cm in horizontal component and vertical component, respectively. The displacement waveforms of Baja California earthquake detected by this GNSS seismometer system are consistent with the results released by Southern California Earthquake Data Center （SCEDC）.