ANALOG CIRCUITS SIMULATION OF COMMUNICATION WITH CHAOTIC LASERS

Masked signal communication between two chaotic lasers,described by ra te equations, was implemented using analog circuits. Digital modulatio n of the gain parameter in the master circuit generated the messages. It is shown that there is a level of modulation for which the receiver circuit decodes the signal by on-off synchronization while the Poinca re sections, the first return maps and the time of return maps recover ed directly from the master signal could not distinguish the bits. The circuits simulate the dynamics of two optically coupled CO2 lasers wi th intracavity saturable absorber. The signal appears to be unbreakabl e in such low dimensional systems because they operate at homoclinic c haos which corresponds to multibranched one-dimensional return maps. ( C) 1997 American Institute of Physics.