Coherence Multiplex System Topologies

Coherence multiplexing is a potentially inexpensive form of optical code-division multiple access, which is particularly suitable for short-range applications with moderate bandwidth requirements, such as access networks, LANs, or interconnects. Various topologies are known for constructing an optical transmission system in which several channels are coherence-multiplexed in one optical fiber. In this paper, the parallel array, the intrinsic reference ladder (IRL), and the discontinuous series system topologies will be further considered and compared with respect to code orthogonality requirements, theoretical performance, and some practical implementation aspects. A modification to the IRL system is proposed, resulting in a significant improvement in the theoretical performance.