The Hartley Phase Cepstrum as a Tool for Signal Analysis

Abstract

This paper proposes the use of the Hartley Phase Cepstrum as a tool for speech signal analysis. The phase of a signal conveys critical information, which is exploited in a variety of applications. The role of phase is particularly important for speech or audio signals. Accurate phase information extraction is a prerequisite for speech applications such as coding, synchronization, synthesis or recognition. However, signal phase extraction is not a straightforward procedure, mainly due to the discontinuities appearing in it (phase ‘wrapping’ effect). Several phase ‘unwrapping’ algorithms have been proposed to overcome this point, when extraction of the accurate phase values is required. In order to extract the phase content of a signal for subsequent utilization, it is necessary to choose a function that can efficiently encapsulate it. In this paper, through comparison of three alternative non-linear phase features, we propose the use of the Hartley Phase Cepstrum (HPC).KeywordsFourier Phase CepstrumHartley Phase CepstrumSpeech signal phasePhase unwrapping algorithm