Abstract
It is one of the most difficult problems in the automatic seismometry system to determine the arrival time of the P-wave and S-wave.
In this paper, a new method to detect earthquakes and determine the arrival time is presented.
The algorithm should be simple, because the quantity of data is very large and rapid analysis is required. In this situation, the most suitable mathematical model of the seismic wave may be an autoregressive (AR) model.
The arrival time of P-wave and S-wave is determined by the log-likelihood ratio function for AR model. In this method, both amplitude and spectral information are effectively utilized and a backtracking process is included which simulates the way taken by the specialist in the manual operation.
The suitable order of the AR model and the numbers of the data in the calculation of AR model are determined from the practical point of view.
The experimental results show that this method is highly reliable and practical.
