Orthogonal wavelength division multiplexing for optical networks

A system and method is disclosed for providing a high-speed, high capacity data communication over Wave Division Multiplexing (WDM) networks. The system employs a first incoming user data stream to select n-bit orthogonal codes from a first code book according to a predetermined code plan. The orthogonal codes are then used to modulate a first light channel, wherein an ON/OFF pattern of the first light channel is the exact representation of the selected orthogonal codes. Similarly, for a second light channel that is adjacent to the first light channel, a second incoming user data stream is encoded with orthogonal codes from a different orthogonal code book. Hence, during data transmission, both the first and second data streams do not have the problem of neighboring channel interfere because the transmitted codes are orthogonal to each other.