Multi-channel, multi-mode redundant optical local loop having a bus topology

摘要

An optical local loop having a bus topology with a pair of optical fibers disposed among a plurality of Optical Network Units (ONUs). A Host Digital Terminal (HDT) is disposed at the head end of the optical local loop for concentrating optical signals for a network. Redundant transceiver banks are provided within the HDT for operating with the optical signals effectuated at a plurality of wavelengths which are multiplexed and de-multiplexed via a pair of Wavelength Division Multiplex (WDM) couplers disposed on corresponding optical fibers. During transmission, the ONUs excite both optical fibers and the received optical signals are monitored in the HDT for quality and integrity of the optical paths. A selectively actuatable mechanism is provided in the HDT to switch downstream transmission to the ONU nodes from one optical path to the other optical path of the local loop based on the path quality and integrity.