Speech coding using Fourier-Bessel expansion of speech signals

Coding of speech signals using Bessel functions as orthogonal signals in the Fourier-Bessel (FB) expansion has been explored. It has been found that a reasonable quality of speech can be reconstructed using a set of 15 to 30 coefficients in the FB expansion of each frame of speech. At 80 frames per second and eight bits per coefficient, this corresponds to a bit rate of as low as 9600 bits/second when predetermined sequence of coefficients are used. The speech quality and the bit rate increase when higher number or a selected set of coefficients are used. Comparable results in perceptual speech quality and frame-to-frame signal-to-noise were observed for both male and female speakers.