Spectral analysis and multi-fractal characteristics of birdsong
ABSTRACT :
A birdsong is a response from a highly complex dynamical system. We have considered the birdsong as a time series. We have analyzed it’s spectral content such as the presence of different syllables, syllabic sequences, and syllabic rate etc. We have studied the time series by analyzing it’s amplitudes. We have observed that the point distribution of the amplitudes have multi-fractal characteristics. To understand the correlation among the amplitudes we have used de-trended fluctuation analysis to avoid the effect of possible trend present in the signal. It shows that the amplitude fluctuation scales as fractional Brownian noise. It also shows that amplitude fluctuations have multi-fractal properties. Using these techniques of multi-fractal characteristics and spectral analysis we want to distinguish between different species through the studies of their songs.