Frequency-wavenumber Analyses by Steered Response Power Phase Transform Algorithm

This paper is devoted to borrowing some knowledge of related field that deals with array data processing to seismology. Steered-response power with phase transform (SRP-PHAT) is a modern signal processing technique that is treated here for application of small-aperture seismic arrays. It was developed in acoustics for effective sound source localization under strong noise and reverberant conditions, which are absolutely similar to those found in seismological applications and even more complex due to wave propagation through nonhomogeneous media. Mathematical representation of this method is given to solve the problem of frequency-wavenumber spectrum density estimation (F-K analysis). The experiments with real seismic array data are presented for two different data sets: The first set belongs to SPITS array data and contains records of P and S phases of the well-known earthquake from 6 October 2006. The second set belongs to temporary array, installed for monitoring and tracking tremor sources. It was shown that SRP-PHAT is a worthy alternative to conventional broadband F-K analysis method involved in most of free and commercial seismological software.