ENGLISH SPEECH SOUNDS: FOURIER ANALYSIS AND SPECTROGRAM STUDIES

Abstract

In this paper, the Fourier analysis and spectrogram techniques for the study of the English speech sounds is discussed. One of the subjects that we will study in this book is the structure of some mathematical functions (namely, the Fourier transform) and some signal processing algorithms reminiscent of the inverse Fourier transform. The paper shows the significance of spectrograms as key visualized representations of acoustic phonetics with which to visually inspect formant structures, voice onset time, and other key temporal-spectral attributes of English phonemes. We use our techniques to demonstrate experimentally the acoustic signatures of vowels and consonants. The paper also covers potential applications in speech recognition, linguistic studies and speech pathology diagnosis. What we find is that, even in an era of increasingly sophisticated acoustic analysis, the Fourier-based spectrograph plays a vital role within modern phonetic research by detailing perceptual principles which cannot be accounted for on the basis of audition alone.

Index Terms: Fourier transform, spectrogram, acoustic phonetics, speech signal processing, formant analysis.