Optical orthogonal codes: Design, . . .

Ahstruct-An optical orthogonal code is a family of (0,l) sequences with good auto-and cross-correlation properties, i.e., the autocorrelation of each sequence exhibits the " thumbtack " shape and the cross correlation between any two sequences remains low throughout. The study of optical orthogonal codes has been motivated by an application in a code-division multiple-access fiber optic channel. The use of optical orthogonal codes enables a large number of asynchronous users to transmit information efficiently and reliably. The thumbtack-shaped autocorrelation facilitates the detection of the desired signal, and low-profiled crosscorrelation reduces interference from unwanted signals. In addition to the wide-hand multiple-access system, optical orthogonal codes also find applications in mobile radio, spread-spectrum communications, and radar and sonar signal design. Methodologies in the design and analysis of optical orthogonal codes with tools from projective geometry, the greedy algorithm, iterative constructions, algebraic coding theory, block design, and various other combinatorial disciplines are discussed.