Phase-orthogonality CDSK: a reliable and effective chaotic communication scheme

To overcome the drawback of bit-error rate (BER) performance decrement caused by intrasignal interference (ISI) in correlation-delay-shift-keying (CDSK) and its enhanced schemes, in this brief, a reliable and effective chaotic communication scheme: phase-orthogonality CDSK is proposed. In the proposed scheme, quadrature sinusoidal wavelets are alternately selected to modulate the reference signal. This operation makes the reference signal strictly orthogonal to the information-bearing signal and the ISI component is eliminated during the demodulation. The BER performance is analytically studied and the simulations are performed in additive white Gaussian noise channel and Rayleigh multipath fading channels. Theoretical analysis and simulations show that, since there is no ISI component and better bandwidth efficiency, the proposed BER performance is much better than differential-chaos-shift-keying (DCSK) and CDSK. With the length of multiframe increasing, the proposed BER performance gradually becomes better, and can even outperform reference-adaptive CDSK and improved DCSK.