Technology

Abstract

Passive optical components are used in the optical distribution network (ODN) and at the optical interfaces connecting the termination equipment with the ODN. The ODN takes care of the connection between the optical network units (ONUs) at the subscriber side and the optical line termination (OLT) at the network, or exchange, side. In the case of an ODN with a tree topology, a major task of the ODN is splitting and combining the optical signal flows between OLT and ONUs. The main components of the ODN are therefore the optical fibre and the optical couplers, having respectively the transport and the splitting/combining functions. Wavelength division multiplexers (WDMs) are wavelength dependent couplers. These are applied when the network makes use of multiple optical wavelengths. The physical connections of ONU and OLT to the ODN will be made with optical connectors. In the ODN, spliced fibre connections are used to make the permanent fibre interconnections.