Easy encoding and low bit-error-rate chaos communication system based on reverse-time chaotic oscillator

A new chaos communication system based on reverse-time chaotic oscillator (RTCO) is proposed in this study. In the system, driven by bipolar sequence, RTCO can directly generate chaotic wave signals that can encode arbitrary binary information, which is much easier than that of the existing chaotic communication scheme in that needs the initial condition estimation. Then the analytical expression of matched filter for the basis function of RTCO is derived. The proposed matched filter is capable of decreasing the effect of noise in the channel. Next, the binary information can be obtained by detecting the summation of multi-sampling during the symbol period through a setting threshold over additive white Gaussian noise (AWGN) channel, which further decreases the influence of noise in decoding procedure. In addition, the binary information can also be obtained over the Rayleigh channel, and its bit error rate (BER) expression is derived. Finally, the feasibility and the validity of the proposed system are given with numerical simulations. It is shown that in the proposed communication system, the encoded chaotic signal is generated with a much simpler method. Furthermore, the BER is lower than that in over AWGN channel, and the performance of the proposed system over Rayleigh channel is better than that of differential-chaos-shift-keying.