NeoPhotonics has announced a multiport mode coupling receiver (MCR) transceiver that enables operators to boost the efficiency of their fibre-to-the-home (FTTH) networks by connecting up to four times as many homes to each existing OLT slot in a central office.
One common approach to reduce the cost of FTTH installation is to keep split ratios high during the initial deployment phase when subscriber take rates can begin low. The new transceiver is designed to increase split ratios by a factor of four without adding additional link loss that could degrade the overall system performance.
The transceiver takes advantage of the fact that several singlemode fibres can be coupled with nearly 100% efficiency to the relatively large area of a detector. This eliminates the need for a splitter in the upstream direction, thus allowing operators to increase the number of homes connected to a single OLT port without increasing the loss budget.
NeoPhotonics acknowledges that the concept is not new, but the implementation in discrete components was too bulky for practical deployment. “The MCR GPON OLT is made possible by our photonic integrated circuit technology,” said Tim Jenks, chairman and CEO of NeoPhotonics.
The first version is a 4-port MCR GPON Class B+ OLT in a pluggable SFP form factor, which is designed to increase the split ratio in a standard PON from 1:32 to 1:128 while maintaining the original link budget and reach. This module is compatible with the installed base of GPON OLT line cards; it features a connector with four fibre outputs where each individual fibre corresponds to the output of a conventional GPON OLT SFP compliant with ITU-T 984 standards. Other versions of the module may be developed in future.
NeoPhotonics co-authored a paper on the mode-coupling receiver, which was presented at ECOC in Amsterdam. The vendor also says that the new transceiver is in qualification with several, unnamed manufacturers of GPON systems.
By Pauline Rigby
Press release: NeoPhotonics Announces New FTTH Component Technology at ECOC