Patent ID: 7787722
Filing Date: 2010-08-31
Classification: H04J

Abstract:
1. A method for coordinating an uplink TDMA access shared by at least two sub-networks of a Passive Optical Network, the first sub-network comprising a first Optical Line Terminal and a first set of Optical Network Units connected to the first Optical Line Terminal through a same splitter, a second sub-network comprising a second Optical Line Terminal and a second set of Optical Network Units connected to the second Optical Line Terminal through the same splitter as used by the first sub-network, each Optical Network Unit belonging to the first sub-network sharing a same first wavelength in a downlink and each Optical Network Unit belonging to the second sub-network sharing a same second wavelength in downlink, the first and second wavelengths being different, each Optical Network Unit belonging to both the first and second sub-networks sharing a same uplink wavelength different from the first and second wavelengths used in downlink direction, the first Optical Line Terminal being able to allocate transmission resources for the TDMA uplink access to be used by the corresponding Optical Network Units of the first set and able to prescribe time of transmissions in the TDMA uplink for the slots to be used by its corresponding Optical Network Units according to the allocated transmission resources and round trip propagation delays between the first Optical Line Terminal and the corresponding Optical Network Units of the first set, the second Optical Line Terminal being able to allocate transmission resources for the TDMA uplink access to be used by the corresponding Optical Network Units of the second set and able to prescribe time of transmissions in the TDMA uplink for the slots to be used by its corresponding Optical Network Units according to the allocated transmission resources and round trip propagation delays between the second Optical Line Terminal and the corresponding Optical Network Units of the second set, comprising the steps consisting of: listening by each Optical Line Terminal all the uplink signalling data sent by all the Optical Network Units of all the sub-networks, characterized in that it comprises the following steps consisting of: determining throughout all the sub-networks a master Optical Network Unit among all the Optical Network Units as the first listened and declared Optical Network Unit by the corresponding master Optical Line Terminal referenced as master Optical Line Terminal, at a local time t in that allocation process of uplink TDMA transmission resources by each Optical Line Terminal to the respective corresponding Optical Network Units is executed in the same way on the basis of the same sequenced uplink signalling data sent by all the Optical Network Units of all the sub-networks , prescription process by each Optical Line Terminal of the time of transmissions in the TDMA uplink for the slots to be used by its corresponding Optical Network Units according to the allocated transmission resources and round trip propagation delays between the Optical Line Terminal and its corresponding Optical Network Units is a same process.