A new development of earth science based on high-rate sampled GPS observations

从模拟和观测两个角度研究了高速率采样GPS数据用于地震计的可行性。仿真结果表明，GPS接收机的输出信号在幅度和相位上都出现了明显的偏移。这种现象预计源于接收机的信号跟踪环路问题，特别是在高于5Hz采样的情况下。还利用三个全球定位系统接收器进行了观测研究。在日本的磐城、鹿岛和静冈放置了接收器，我们以50 Hz的采样率进行了观测。结果，在2013年9月20日发生在磐城市附近的福岛县的地震中，日本气象厅记录的烈度为5+的地震，在GPS数据中得到了清晰的记录。

Feasibility of using high-rate sampled GPS data for seismometer was investigated from the stand point of both simulations and observations. Results using a simulator suggested that it appears significant shift in both amplitude and phase in the output signal from the GPS receivers. This phenomenon is expected to stem from the signal tracking loop problem of receivers, especially in case of higher than 5Hz sampling. Observational studies using three GPS receivers have also been conducted. The receivers were placed at Iwaki, Kajima and Shizuoka, Japan, and we conducted observations with sampling rate of 50Hz. As a result, the ground shake due to the September 20, 2013 earthquake that occurred in Fukushima prefecture nearly below Iwaki site and registered JMA intensity 5+, was clearly recorded in the GPS data.