A Preliminary Study of Development of Standard Background Noise Model for the KMA Infrasound Stations

Abstract

The infrasound is transmitted through the air, so the characteristics are changed by temperatures, humidity, and wind of the air. It is difficult to obtain high quality infrasound signals due to the background noise. The main sources of the background noise are human activities and wind. The development of a background noise model that quantifies the frequency band is important in the design of filters to improve the signal-to-noise ratio.In order to secure the quality of the infrasound signals. In this paper, we obtain the power spectral densities for the year of the 2015 infrasound recordings of Yanggu and Cheolwon station, and develop the model that obtained by maximum density per frequency in the upper 95% and lower 5% regions. Power spectral density analysis showed that the Yanggu station had relatively higher noise levels than the Cheolwon station and exceeded the international standard background noise model in certain frequency bands. The analysis of the meteorological data for the year of 2015 shows that the wind interfered the signal due to the high altitude of the station. The results of this paper are expected to be used as a background noise model to obtain high quality infrasound data. Keywords: Power Spectral Density, Infrasound Station of KMA, Background Noise