Abstract
In order to improve frequency-response estimation in earthquake early warning, we introduce a new source parameter, "frequency-response magnitude (Mres)" that can be calculated for each natural frequency from observed P-wave data using a pre-established attenuation relation. Users can easily estimate frequency responses of their target systems by using the attenuation relation and Mres which is issued from EEW center (i.e. JMA). Data analysis for 6 different systems (natural frequency: 0.25-8.0 Hz, damping: 5%), with a use of 12793 waveforms for 115 earthquakes (3.5<Mjma<8.0) recorded by Hi-net seismic array, shows 14-22% (from S-wave) or 10-18% (from P-wave) error reduction of response estimation by Mres compared with that by the conventional JMA magnitude. This result indicates Mres is a very effective source parameter to estimate accurate frequency response in EEW and it may be useful especially for automatic controlling systems.
