Source separation for decryption in chaos-masked optical transmission systems

Conventional chaotic communication relies on high-quality chaos synchronization, but this is difficult to achieve in practice due to the extreme parameter sensitivity of communication systems based on chaos synchronization. Unlike previous works, the proposed scheme utilizes a source separation approach to decrypt the message at the receiver end by separating it directly from chaos at the receiver side. In this paper, we take Conv-TasNet as an example to illustrate the feasibility of the separation scheme and achieve decryption at a low bit error rate(BER). The robustness of the separation performance to noise (demonstrated as signal-to-noise ratio (SNR)), masking coefficient, bit rate of the message, and parameters of the chaotic transmitter are studied. Simulation results show that the proposed system has low sensitivity to time delay signature (TDS). Simultaneously, the bit rate of the message, the overall gain of the electro-optical feedback loop, the high-pass cutoff frequency, and the masking coefficient could significantly affect the separation performance.