Variable-weight optical orthogonal codes for CDMA networks with multiple performance requirements

An optical orthogonal code (OOC) is a family of (0,1) sequences with good auto- and cross-correlation properties; they are used as a means to obtain code division multiple access (CDMA) on fiber optic networks. Previous work on OOC has assumed that the weight of each codeword is the same. We consider codes when this assumption is removed. We develop bounds on the size of such "variable-weight" OOC's and demonstrate techniques to build them. Furthermore, we provide an analysis of the performance of variable-weight OOC in a CDMA network. Varying the weight of a user's signature sequence affects that user's performance; therefore this approach is useful for CDMA fiber optic networks with multiple performance requirements.