Impact of filtering chaotic signals on secure wireless communication systems based Chua´s circuit

One of the challenging issues involved in the development of future chaos-based secure communication (CBSC) for wireless applications is the synchronization between transmit and receive nodes. In this paper, effects of filtering chaotic signals of CBSC due to finite bandwidth of realistic channel environment and/or detection requirements on the synchronization are investigated. The double scroll chaotic attractor using Chua´s circuit is employed at the transmit and receive nodes. Over wide range of filter cut-off frequency (η), simulation results show that as η decreased, below the bandwidth of chaotic signal (W), the synchronization error is increased due to high distortion in the normal geometrical configuration (state-space) of the attractor. Consequently, the system performance will be degraded significantly with high possibility of communication link failure. Thus, careful design should be made to eliminate the impact of filtering and achieve the essential synchronization towards the wide adoption of CBSC in next-generation systems.