Demonstration of a transparent router for wavelength-hopping time-spreading optical CDMA

We propose and demonstrate a two-dimensional wavelength-hopping time-spreading optical code division multiple access (OCDMA) node architecture for all-optical path networks. An OCDMA-based network can provide optically transparent and reconfigurable paths for on-demand high-bandwidth optical connections. The network node consists of parallel code converter routers (PCCRs), which perform routing by passive code conversion, the destination address of the data sent being an OCDMA code. We present an experimental demonstration of this OCDMA node in a 4-station mesh network operating at 253 Gchips/s with a single user bit rate of 2.5 Gb/s. We show the capability of the node to create reconfigurable code paths (CPs) and virtual code paths (VCPs). Our proposed architecture provides an all-optical method to create reconfigurable paths, while reducing switching delays and node complexity. Due to the inherent flexibility of OCDMA, path networks can rapidly respond to failure or changes in load condition while accommodating a large number of users.