The precursor signal detection from electromagnetic waves for predicting great earthquakes using Kalman filter

摘要

The tectonic activities that precede significant earthquakes release electromagnetic (EM) waves that can be used as earthquake precursors. We have been observing EM radiation in the extremely low frequency band at over 40 observation stations in Japan for predicting significant earthquakes. However, the recorded signals contain several noise components generated from the ionosphere, human activity, and so on. Most background noise in observed signal is attributed to lightning in the tropics. In this paper, we introduce a state space model and Kalman filter to reduce the noise. The good performance of the proposed model is confirmed.