Secured Communication of Speech Signal Using the Discrete Cosine Transform Based on Hyperchaos-System

Abstract

This paper proposes a novel approach that combines chaos-based encryption and Discrete Cosine Transform (DCT) to ensure high-level speech security and robustness against attacks. In this approach, the encryption process is based on Lorenz’s hyperchaotic system, which utilizes the One Time Pad approach to encrypt the speech DCT coefficients. The effectiveness of this approach has been validated through experiments on two PCs interconnected via real-time serial communication links (USB-RS232), which showed that the original speech is effectively hidden, and the proposed solution is highly resistant to possible attacks. Moreover, the proposed solution can be implemented in real-time applications using technologies such as FPGA.