No abstract

Synchronization of nonlinear systems forced by external signals is formalized as the response of a nonlinear filter. Sufficient conditions for a nonlinear system to behave as a filter are given. Some examples of generalized chaos synchronization are shown to actually be special cases of nonlinear filtering.

This work presents a forced synchronization phenomenon like the asymptotic correlated behavior between chaotic oscillators forced by an external signal. Different kinds of forced synchronization are presented and given a theoretical justification explaining why it is possible to find some of them. Numerical results are presented for different cases such as antisymmetric, lag, phase, and identical forced synchronization.

For the energy detector (ED) employment as a coarse spectrum sensor in cognitive radio (CR) systems, a closed form expression of the optimal detection threshold is derived under spatially correlated multiple antennas and noise variance uncertainty based on probability of error minimization criterion. The ED sensing performance is analyzed using the probability of error as a function of the sample complexity and normalized detection threshold. The obtained results can be generalized to different types of fading channels.