Abstract: Fault analysis of a Passive Optical Network comprising Optical Network Terminal(s) uses Optical Time Domain Reflectometry (OTDR). An OTDR measurement signal is supplied to a multistage splitter having a ratio 2:Nroot. At least one drop link which is connected to the multistage splitter comprises one or more sub-splitters which having a ratio 1:Nbranch. A new event location is determined based on the OTDR measurement signal by analyzing OTDR measurement data relating to the sub-splitter based on distance from the multistage splitter and to the sub-splitter. A fault magnitude is calculated for a given location by subtracting an event magnitude obtained from the new OTDR measurement from a reference OTDR measurement and taking into account the number of drop links connected to the last splitter stage and to the sub-splitter in the reference measurement and the new measurement, thereby enabling determination of position and severity of the fault locations.

Abstract: An arrangement in a node in a WDM-PON and a method therein for supervision of the WDM-PON are provided. The arrangement comprises X splitters of splitting ratio 1:Y, each splitter having one input and Y outputs such that X*Y equals N, wherein X, Y, N are integers. The one input of each of the X splitters is configured to receive an Optical Time Domain Reflectometry, OTDR, signal and to split the received OTDR signal into Y OTDR sub-signals such that a total of N OTDR sub-signals are outputted from the X splitters. The arrangement further comprises an N*N Arrayed Waveguide Grating, AWG, and a first filter configured to mix a feeder signal comprising data communication from an Optical Line Termination, OLT, with one of the N OTDR sub-signals. One input of the AWG is configured to receive the mix of the feeder signal and the one OTDR sub-signal, and the remaining N-inputs of the AWG are each configured to receive a respective one of the N-remaining OTDR sub-signals.

Abstract: An arrangement at a Remote Node, a Remote Node, a Central Office, a WDM-PON and a method in an arrangement at a Remote Node, and a method in a Central Office are provided for supervision of the WDM-PON. The arrangement comprises at least one filter connected to the feeder fibre links and adapted to separate a data signal and an original OTDR signal received on either of the feeder fibre links. Further, the arrangement comprises a first splitter adapted to receive, from the at least one filter, the original OTDR signal, to split the original OTDR signal into a plurality of OTDR sub-signals and to output, to an N*M AWG, the plurality of OTDR sub-signals. The at least one filter is further adapted to output the original OTDR signal to the first splitter and to output the data signal to the AWG, thereby enabling supervision of the WDM-PON.

Abstract: The present invention relates to a transceiver unit in a PON, Passive Optical Network, for receiving an optical input signal and transmitting an amplitude modulated optical output signal. Further, the present invention relates to a method in a transceiver unit for receiving an optical input signal and transmitting an amplitude modulated optical output signal.

Abstract: A client unit and a method are provided performing fault analysis in a Passive Optical Network, PON, by using Optical Time Domain Reflectometry, OTDR. The method comprises triggering a new OTDR measurement, wherein a previous reference measurement has been made indicating an original state of the PON. The method further comprises inserting an OTDR measurement signal into a multistage splitter before a last splitter stage of the multistage splitter, and wherein the last splitter stage is of ratio 2:N; and obtaining at least one new event location based on the OTDR measurement signal. Further, the method comprises calculating a fault magnitude at a given location by subtracting an event magnitude obtained from the new OTDR measurement from the reference OTDR measurement and taking into account the number of drop links connected to the last splitter stage in the reference measurement and the new measurement. Thereby, determination of position and severity of the fault locations is enabled.

Abstract: The present invention relates to a transceiver unit in a PON, Passive Optical Network, for receiving an optical input signal and transmitting an amplitude modulated optical output signal. Further, the present invention relates to a method in a transceiver unit for receiving an optical input signal and transmitting an amplitude modulated optical output signal.