Single Channel Phase-Aware Signal Processing in Speech Communication

Chapter 1Introduction: Phase Processing, History

Pejman Mowlaee

Graz University of Technology, Graz, Austria

1.1 Chapter Organization

This chapter provides the historical background on phase-aware signal processing. We will review the controversial viewpoints on this topic so that the chapter in particular addresses two fundamental questions:

• Is the spectral phase important?
• To what extent does the phase spectrum affect human auditory perception?

To answer the first question, the chapter covers the up-to-date literature on the significance of phase information in signal processing in general and speech or audio signal processing in particular. We provide examples of phase importance in diverse applications in speech communication. The wide diversity in the range of applications highlights the significance of phase information and the momentum developed in recent years to incorporate phase information in speech signal processing. To answer the second question, we will present several key experiments made by researchers in the literature, in order to examine the importance of the phase spectrum in signal processing. Throughout these experiments, we will examine the key statements made by the researchers in favor of or against phase importance. Finally, the structure of the book with regard to its chapters will be explained.

1.2 Conventional Speech Communication

Speech is the most common method of communication between humans. Technology moves toward incorporating more listening ...