Analysis and Processing of Audio Signals Using Complex Form Representation

Abstract

The subject of study is a complex presentation of audio signals. The aim of the work are proposals for the development of methods for monitoring, processing and compact representation of audio signals based on their complex form presentation. It is shown that almost all channels that transmit a sound signal adaptively change their characteristics in accordance with the properties of the signal, which does not allow preserving of waveform original shape. It is shown that the main dif?culties are associated with the need to ensure high accuracy of the formation of an orthogonal signal for wideband audio signals. Attention is drawn to the fact that the accuracy of the synthesis of an orthogonal signal is largely determined by the correct selection of the window function used in the FFT. It is shown that the representation of the audio signal in the form of an analytical envelope and cosine of the instantaneous phase made it possible to develop an original, almost instantaneous method of controlling the levels of the audio signal, making it possible to signi?cantly increase its relative average power without changing the dynamic range of the signal. Based on the use of the averaged instantaneous frequency of the signal, selected as a result of the complex form presentation of this sound signal, a new method of adaptive ?ltering has been developed.

Keywords

• Audio signal
• complex signal representation
• orthogonal conversion error
• Hilbert transform of a wideband signal
• instantaneous control method