earticle

영어

Blind deconvolution of Green’s Function (GF) as well as the Source Time Function (STF) is a fundamental problem in seismic signal processing. This paper presents a comparative study of two blind deconvolution methods for determining the Green’s function as well as the source time function from the recorded seismic data. We have tested these algorithms on the December 26, 2004 Sumatra earthquake (Mw=9.3). An improvised Least Mean Square (LMS) algorithm has been used to improve the multi-pulse method proposed earlier by Cookey et al. [1]. We have also evaluated the performance of this improvised multi-pulse method against the Frequency-Domain Blind Deconvolution (FDBD) method. The FDBD method is based on Mutual Information Rate (MIR) proposed by Larue et al. [3]. These methods have also been tested for some of the records of the earthquake at different stations worldwide available on IRIS-dataset. We have found the azimuthal dependency of the source time function on these records. We have also compared both the methods using synthetic as well as real data. The STFs recovered on different stations using multi-pulse model and FDBD method show similarity in shape and duration as well. However the proposed improvisation on the multipulse method is computationally efficient.