Article

# Code division multiple-access techniques in optical fiber networks. I. Fundamental principles

• ##### J.A. Salehi
Bell Commun. Res., Morristown, NJ
IEEE Transactions on Communications (Impact Factor: 1.75). 09/1989; DOI: 10.1109/26.31181
Source: IEEE Xplore

ABSTRACT An examination is made of fiber-optic code-division
multiple-access (FO-CDMA), a technique in which low information data
rates are mapped into very-high-rate address codes (signature sequences)
for the purpose of achieving random, asynchronous communications free of
network control, among many users. The need for a special class of
signature sequences to achieve the multiple-access capability using
fiber-optic signal processing techniques is discussed. A class of
signature sequences called optical orthogonal codes (OOCs) that provide
the auto- and cross-correlation properties required for FO-CDMA is
introduced and used in an experiment to show the principles of FO-CDMA.
The experiment demonstrates the auto- and cross-correlation properties
of the codes. The concept of optical disk patterns, an equivalent way of
representing the OOCs, is introduced. The patterns are used to derive
the probability density functions associated with any two interfering
OOCs. A detailed study of different interference patterns is presented,
and the strongest and the weakest interference patterns are determined

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