Abstract

Recent advances in the development of techniques for controlling chaos have motivated efforts to implement secure communication systems which exploit the properties of chaotic dynamical systems.¹ Chaotic communications may also be effected by mixing the message signal with the output from a chaotic transmitter and then recovering the message from the transmitted chaos.² An efficient algorithm for improving the receiver/transmitter locking has been reported recently.³ An essential ingredient in controlling chaotic dynamics is the procedure for targeting the periodic or unstable orbit which will be utilised to carry the transmitted information. In earlier work⁴ it has been shown that periodic orbits can be targeted using loss modulation. In the present work it is demonstrated that gain switching of external cavity laser diodes can be used for targeting periodic orbits. Such a device configuration can then be utilised in a chaotic optical communications system.

© 1995 IEEE