Two-channel opto-electronic chaotic communication system

We propose and implement experimentally an opto-electronic chaotic communication system based on chaos synchronization, which uses two channels: the electronic channel for synchronization and the optical channel for information transmission. Both the transmitter and the receiver contain identical chaotic Rِssler-like electronic circuits and identical continuous wave semiconductor lasers. The circuit in the receiver is synchronized with the circuit in the transmitter by one of the variables via the electronic channel, while another variable serves to drive the laser pump current chaotically. Due to the functional dependence of the circuit variables, the signals transmitted through the electronic and optical channels are also functionally dependent. A message is encrypted into the laser output in the transmitter and sent to the receiver via the optical channel, where the received waveform is compared with the laser output in the receiver. Since the lasers in the transmitter and in the receiver are completely synchronized, the message is retrieved with a very good precision.