Author(s)

T. Benmakhlouf, S. Mekaoui & K. Ghoumid

Abstract

The main aim of this paper is concerned with modern telecommunications systems which involve modern methods of coding, encryption and decryption of speech signals. For a long time, for the transmission of a speech signal analog telecommunications systems have been used. Because of unexpected and unavoidable interference, wave fading perturbations and different kinds of noise occurring in the channel, it was not possible to detect and receive the same transmitted speech signal. Consequently, digital systems have steadily replaced the former. Here, we have simulated two blocks of such systems, namely the source coding block and the encryption/decryption block. We tested them by listening to the synthesized signals via headphones and using a simulation operated using Simulink of the source software Matlab. Although metallic in their tonalities, results were found to be acceptable. Keywords: digital speech signal processing, digital data transmission, Simulink, LPC algorithm, AES algorithm, time-frequency analysis, STFT transform, analysis/synthesis of speech signal.

Keywords

Keywords: digital speech signal processing, digital data transmission, Simulink, LPC algorithm, AES algorithm, time-frequency analysis, STFT transform, analysis/synthesis of speech signal.