The psychoacoustic approach towards enhancing speech intelligibility in noise

Abstract

In this paper, we propose a psychoacoustic approach towards enhancing speech intelligibility in noise. Understanding the relationship between the short-term spectral movement of a sound and a listener's sensitivity towards it, we conjecture that humans rely greatly on Inter-Phoneme Spectral Gradients (IPSGs) to distinguish each phoneme, especially when the short-term speech spectrum is masked by extremely high levels of noise. We then move on to explain how the IPSG may most effectively be steepened while introducing the concept of Formant Contrast. The effectiveness of this process is validated with spectral analysis and listening tests, verifying that our initial deduction is true. In these, we present a simple, yet novel and effective method of improving speech intelligibility - especially in extremely high noise environments.