Embodiments of the present invention provide an optical network unit ONU registration method, apparatus, and system, to resolve a problem in the prior art that a registration process is cumbersome. The method includes: receiving an uplink optical signal, where the uplink optical signal carries ONU authentication information; sending the optical signal to a corresponding MAC module separately according to a wavelength of uplink light; extracting, by the MAC module, the ONU authentication information, and sending the extracted ONU authentication information to a processor; and receiving, by the processor, the ONU authentication information, and determining whether the ONU authentication information is consistent with ONU authentication information configured by an OLT, where if the ONU authentication information is consistent with the ONU authentication information configured by the OLT, an ONU is registered successfully.

A method and apparatus for communications in a passive optical network (PON) system are provided. An optical line terminal (OLT) generates a PON downstream Physical Layer (PHY) frame comprising a downstream physical synchronization block (PSBd) that comprises a wavelength identification (ID) of at least one downstream wavelength of the plurality of downstream wavelengths. The OLT sends the PON PHY frame comprising the wavelength ID in the PSBd to ONU for confirming the at least one downstream wavelength.

One embodiment relates to a method for transmitting data via an optical network comprising a plurality of optical nodes, in which at least one wavelength is dedicated to the transmission, in the network, of data bursts transmitted by at least one source node and wherein the data bursts are intended for an addressee node. The method may comprise transmitting a control message from the addressee node to the at least one source node wherein the control message is conveyed in an optical signal emitted according to the wavelength dedicated to the transmission, in the network, of data bursts intended for the addressee node.

The inclusion of a pilot tone as a modulation of an optical data signal reduces the optical signal to noise ratio (OSNR). Methods and apparatus for receiving an optical signal are provided that compensate for at least a portion of the pilot tone modulation to reduce the pilot tone induced OSNR penalty. An initial waveform is processed to generate a compensated waveform, the processing including dispersion compensation. An intensity waveform is calculated in accordance with the compensated waveform. The intensity waveform is processed to obtain a pilot tone frequency, a modulation depth, and a phase of the pilot tone. The compensated waveform is multiplied with a pilot tone compensation factor that is a function of the pilot tone frequency, the modulation depth, and the phase of the pilot tone to generate a modified compensated waveform. A symbol carried by the modified compensated waveform is determined.

A method for generating a tone signal (TS) having a tone frequency, f, wherein the method comprises the following steps: supplying (S1) a binary bit stream (BBS) having a mark pattern with a supply bit rate, BR, to a signal filter unit; and filtering (S2) the supplied binary bit stream (BBS) by said signal filter unit to generate the tone signal (TS), wherein the mark pattern of the binary bit stream (BBS) supplied to said signal filter unit is adapted to minimize a ratio of the supply bit rate, BR, to the tone frequency, f, of the generated tone signal (TS).

An apparatus comprises: a processor configured to: select a first channel from among a plurality of channels in a network, and generate a first message assigning a first grant corresponding to the first channel; a transmitter coupled to the processor and configured to transmit the first message; and a receiver coupled to the processor and configured to receive a second message on the first channel and in response to the first message. A method comprises: selecting a first channel from among a plurality of channels in a network; generating a first message assigning a first grant corresponding to the first channel; transmitting the first message; and receiving a second message on the first channel in response to the first message.

The invention provides a method for labeling an optical fiber wavelength, including: deploying a spreading code on each of a transmit end and a receive end; transmitting a message code, and spreading the message code by using the spreading code of the transmit end; and performing envelope modulation on an optical signal by using the spread message code, transmitting the optical signal after the envelope modulation to the receive end, choosing, the spreading code of the receive end to despread the message code to obtain the original message code of the transmit end, and obtaining a corresponding wavelength according to the spreading code of the receive end. A spreading code having a correspondence with a wavelength is used to spread and despread a message code, and a modulation depth of an amplitude modulated signal may be greatly reduced to nearly prevent an envelope modulated signal from affecting a main signal.

The present invention discloses a passive optical network communications method, reporting, by an optical network unit, ONU, a calibration record of the ONU, where the calibration record includes an ID of a calibrated wavelength channel; sending a first message to the ONU when the OLT determines, according to the calibration record, that a target wavelength channel ID corresponding to a target wavelength channel to which the ONU needs to switch is not in the calibration record, where the first message includes a forced wavelength switching flag; and instructing the ONU to switch to the calibrated target wavelength channel. In this way, the ONU can implement wavelength switching quickly after calibrating a new wavelength channel so as to perform data communication over the calibrated new wavelength channel.

In order to identify occupied bands in an optical transmitter with high accuracy, a band identifying circuit includes an optical intensity controller configured to change, by a prescribed level, an optical intensity of an optical signal outputted from a target-of-identification optical transmitter among a plurality of optical signals respectively outputted from a plurality of optical transmitters, constituting a wavelength-multiplexed optical signal, and having mutually different wavelengths, a spectrum acquisition circuit configured to measure an optical intensity of each wavelength of the wavelength-multiplexed optical signal and output a result of the measurement as a spectrum, and a band identifier configured to identify a band occupied by the target-of-identification optical transmitter, based on a change amount of the outputted spectrum.

A method and apparatus for communications in a passive optical network (PON) system are provided. An optical line terminal (OLT) generates a PON downstream Physical Layer (PHY) frame comprising a downstream physical synchronization block (PSBd) that comprises a wavelength identification (ID) of at least one downstream wavelength of the plurality of downstream wavelengths. The OLT sends the PON PHY frame comprising the wavelength ID in the PSBd to ONU for confirming the at least one downstream wavelength.