Signal Enhancement of Acoustic Signature of Lutjanidae Family Species in Indian Waters

Abstract

The present study is to carry out the enhancement of the acoustic signals of Lutjanidae species often found in abundance, in tropic shallow waters. Since most of the studies on Lutjanidae is about its physical structure both internal and external, and its population in sea ie., catches in tons per year. This research work is the first attempt on the acoustical study of Lutjanidae family species call signal. Five species of Lutjanidae family are considered for this study which includes L. analis, L. apodus, L. synagris, L. griseus, and L. jocu). The earlier literature which studied the acoustic toning of marine species vocalization using empirical mode decomposition method [1]. Here in this research, (i) signals with background noise and (ii) enhanced signals are considered for comparison. The enhancement of acoustic signals of Lutjanidae family species is useful as acoustic reference for those working in the field of biological signal processing. The enhancement of the signal is achieved by the logical applications and applying Short Time Fourier Transform (STFT), inverse STFT. From the above two cases considered, the frequency range of 50 to 2500 Hz approximately is clearly noticed in the spectrogram, power spectral density and it shows the frequency of all species looks similar. By listening the sound produced by the species, it is observed to be of type knocking sound.