On optimal detection of noncoherent chaos-shift-keying signals in a noisy environment

Recently, an optimal noncoherent detection technique for chaos-shift-keying digital communication system has been proposed. It has been stated that computational intensity showed increases that were exponential with the spreading factor. In this Letter, we show that the implementation of the optimal detector can be made independent of the chaotic maps used, and that the computational intensity will increase almost linearly with the spreading factor. In particular, we use a tent map as an example to illustrate the decoding algorithm. The bit error performance of the system is then evaluated by computer simulations for a range of spreading factors. Further, we extend the optimal decoding algorithm for maps of higher dimension. The bit error performance for the case of simple 2-D maps are compared with that obtained using the tent map. Finally, the effect of increasing spreading factor on the bit error performance is studied for the case of 2-D maps.