Enhancing Chaotic Communication Performances by

A numerical analysis of an optical chaotic transmis- sion system, based on the synchronization of two chaotic lasers, in a master-slave closed loop configuration is presented. At the trans- mitter, the master chaotic wave is superposed on the information message; at the receiver, the message is recovered by subtracting the synchronized slave chaotic wave from the received signal. The performances are analyzed in terms of the -factor, considering two different message modulation formats: the nonreturn-to-zero and the Manchester coding. The Manchester coding shows en- hanced performances due to the shift of the signal spectrum to higher frequencies. Index Terms—Chaos, encryption, Manchester code, -factor, synchronization.