Optical data communications network with a plurality of optical transmitters and a common optical receiver connected via a passive optical network

摘要

An optical data communications network, for example a TPON (telecommunications over passive optical networks) network, has a common optical receiver and a plurality of optical transmitters connected to the common optical receiver by a passive optical network which consists of optical splitters/combiners linked by lengths of an optical fibre. The optical signals produced respectively by the different optical transmitters are interleaved together in a predetermined time-division multiple access format and are modulated using a return-to-zero modulation format. The common optical receiver can operate satisfactorily at desirably-high bit rates despite wide variations in the power levels of the optical signals reaching the receiver from the different transmitters, which variations arise due to the different attenuations experienced by those signals as they propagate along optical fibre paths of different lengths containing different numbers of splitters/combiners. As a result, power levelling of the transmitters is not required.