Chaotic Communication System of Noise Reduction Multi-carrier with No Intra-signal Interference CDSK

To address the high bit error rate (BER) in conventional correlation delay shift keying (CDSK) communication systems, this paper proposes a noise-suppressed multi-carrier CDSK communication scheme with intra-signal interference elimination, referred to as NISI-NRMC-CDSK. At the transmitter, a switching structure is introduced to generate two strictly orthogonal chaotic sequences, each of which is replicated P times and combined with N sets of information sequences for transmission. Multi-carrier modulation allows each signal frame to carry two bits. At the receiver side, a moving average filter is employed to suppress noise within the decision variables, thereby significantly reducing the BER. Theoretical BER expressions under AWGN and Rayleigh fading channels are derived and validated through Monte Carlo simulations. Simulation results validate the robustness of the proposed system and show that its BER performance significantly outperforms existing chaotic communication schemes, especially in the presence of noise and multipath interference.