Dispersion in multiwavelength optical code-division multiple-access systems: impact and remedies

Temporal skewing, a hitherto unexamined effect of chromatic dispersion on multiwavelength optical code-division multiple-access (MW-O-CDMA) systems, is explored through simulation of realistic networks. In addition, two novel methods for combating the deleterious effects of temporal skewing are proposed: optimum threshold detection and code-pattern preskewing. It is shown that for a practical system configuration with optimum threshold detection, MW-O-CDMA networks can maintain design bit error rate performance within an order of magnitude for link lengths of up to approximately 500 m. Our results show that the effect merits careful attention in the design and realization of any MW-O-CDMA system based on two-dimensional codes. Code pattern preskewing presents the possibility of completely eradicating the impact of temporal skewing. Index Terms--Chromatic dispersion, local-area networks, multiwavelength optical networks, optical code-division multiple access, temporal skewing.