SIGNIFICANCE OF GROUP-DELAY FUNCTIONS IN SIGNAL PROCESSING.

We propose a new method of representation of signals using group-delay functions and demonstrate its applications in signal processing. We define two separate group-delay functions for a signal, one derived from the magnitude of the Fourier transform of the signal and the other from the phase. We discuss the properties of these functions and show how they can be exploited for formant extraction in speech pole-zero modelling, digital filter design and signal reconstruction problems.