학술논문

RF-Interferences Generate Chaotic GHz FM Carrier for Communications.
Document Type
Article
Source
IEEE Journal of Quantum Electronics. May/Jun2007, Vol. 43 Issue 5/6, p426-433. 8p.
Subject
*OSCILLATIONS
*TELECOMMUNICATION systems
*INTERFEROMETERS
*OPTICAL instruments
*PHOTODIODES
Language
ISSN
0018-9197
Abstract
Following the principle of a highly nonlinear delay oscillator, we demonstrate the generation of an RF chaotic frequency modulated carrier, which could be used in chaos based communication systems. The nonlinear process is provided by the transfer function of an RF interferometer, modulating the amplitude of an FM signal; for this purpose, the path difference required for the interference process, as well as a long delay required for complex chaotic oscillation, are designed through the use of optical fibers. The RF signal used to produce interferences is transposed in the optical domain by a direct laser modulation with the gigahertz chaotic FM signal. The interference is obtained at fiber outputs terminated by photodiodes for backconversion of the RF signal into the electrical domain. Experimental results reporting the particular dynamical behavior of the nonlinear delay RF oscillator are presented, and also discussed in terms of chaos communication applications. [ABSTRACT FROM AUTHOR]