Some extensions to synchronous O/O systems

We discuss some extensions to the conventional OCDMA/OCDMA (O/O) system. First of all, synchronous O/O, defined for spreading gain N = 2/sup n/ is extended to any spreading gain that is a multiple of 4. In a second step, we consider the performance of O/O systems, where the signatures of the two orthogonal sets are displaced with respect to each other. It is found that this displacement can result in a significant performance improvement.