An approach to calculating the bit-error rate of a coherent chaos-shift-keying digital communication system under a noisy multiuser environment

Assuming ideal synchronization at the receivers, an approach to calculating the approximate theoretical bit-error rate (BER) of a coherent chaos-shift-keying (CSK) digital communication system under an additive white Gaussian noise environment is presented. The operation of a single-user coherent CSK system is reviewed and the BER is derived. Using a simple cubic map as the chaos generator, it is demonstrated that the calculated BERs are consistent with those found from simulations. A multiuser coherent CSK system is then defined and the BER is derived in terms of the noise intensity and the number of users. Finally, the computed BERs under a multiuser environment are compared with the simulation results.