CAPACITY BOUNDING OF COHERENCE MULTIPLEXED LOCAL-AREA NETWORKS DUE TOINTERFEROMETRIC NOISE

Coherence multiplexing exploits the coherence properties of optical so urces so that many users may be multiplexed onto a single physical cha nnel giving a secure, asynchronous mode of transmission, free of centr al network control. In the paper, for the first time, the system perfo rmance limitations owing to the impact of interference from unwanted u sers is presented and the suitability of LED, single-mode Fabry-Perot laser and DFB sources are considered. It is concluded that the single- mode Fabry-Perot is preferred, offering readily achievable interferome ter length tolerances and near complete RF rejection of interferometri c noise at the receiver. However, interferometric noise still limits t he network capacity: a linewidth of 1nm permits 17 users to be simulta neously offered a single video channel with a BER < 10(-9).