A passive optical network includes a central office providing subscriber signals; a drop terminal; and a wave division multiplexer. A fiber distribution hub may split or separate out dedicated optical signals from subscriber optical signals between the central office and the drop terminal. The wave division multiplexer separates dedicated optical signals pertaining to a specific dedicated subscriber from other optical signals on the line received at the wave division multiplexer. The wave division multiplexer may be part of a cable or part of an intermediate service terminal.

Systems, apparatuses, methods, and computer program products are disclosed for managing premise-level data communication in a wavelength division multiplexing (WDM) fiber optic network. An example method includes receiving, by a control system, a message from a new device connected to the WDM fiber optic network, the message including one or more service provider identifiers, a customer identifier, and a customer equipment identifier of the new device. The method further includes transmitting, by the control system, a configuration command to the new device, the configuration command including (i) an indication of which wavelengths the new device may utilize, and (ii) an indication of message types that may be transmitted using each wavelength the new device may utilize. The method further includes causing, by the control system, transmission of a service fee to each service provider associated with a service provider identifier of the one or more service provider identifiers.

A coherent passive optical network includes a downstream transceiver and first and second upstream transceivers in communication with an optical transport medium. The downstream transceiver includes a downstream processor for mapping a downstream data stream to a plurality of sub-bands, and a downstream transmitter for transmitting a downstream optical signal modulated with the plurality of sub-bands. The first upstream transceiver includes a first local oscillator (LO) for tuning a first LO center frequency to a first sub-band of the plurality of sub-bands, and a first downstream receiver for coherently detecting the downstream optical signal within the first sub-band. The second upstream transceiver includes a second downstream receiver configured for coherently detecting the downstream optical signal within a second sub-band of the plurality of sub-bands. The downstream processor dynamically allocates the first and second sub-bands to the first and second transceivers in the time and frequency domains.

Embodiments of this application provide an OLT, an ONU, and a system. In a downlink direction, the first OLT is configured to convert received downlink data packets of M1 paths into one downlink optical signal whose wavelength is λo, and the first ONU is configured to receive the downlink optical signal, and output a target user data packet after processing the downlink optical signal. In an uplink direction, the first ONU is configured to convert received uplink data packets into an uplink optical signal whose wavelength is λi, and the first OLT is configured to receive a plurality of uplink optical signals of different wavelengths, and output user data packets of a corresponding quantity of paths after processing.

Methods and apparatuses are provided to modify existing overlay system architectures in a cost effective manner to meet the growing demand for narrowcast services and to position the existing overlay systems for additional future modifications. The implementations of the improved overlay system of this disclosure re-digitize narrowcast analog signals after they have been QAM modulated and upconverted to RF frequencies and replace the analog narrowcast transmitters with digital narrowcast transmitters. In the fiber nodes, the received narrowcast signals are converted back to analog signals and combined with analog broadcast signals for transmission to the service groups.

Digital information can be carried on the fiber leg of an access network using binary modulation. Binary modulated data received at an O/E node can then be modulated onto an analog waveform using quadrature amplitude modulation or some other technique for modulating an analog waveform and transmitted over, for example, the coaxial leg of the network. The O/E node may also receive an analog signal, over the coaxial leg, modulated to carry upstream data from subscriber devices. The O/E node may demodulate the upstream signal to recover the upstream data and forward that upstream data over the fiber leg using a binary modulated optical signal.

Digital information can be carried on the fiber leg of an access network using binary modulation. Binary modulated data received at an O/E node can then be modulated onto an analog waveform using quadrature amplitude modulation or some other technique for modulating an analog waveform and transmitted over, for example, the coaxial leg of the network. The O/E node may also receive an analog signal, over the coaxial leg, modulated to carry upstream data from subscriber devices. The O/E node may demodulate the upstream signal to recover the upstream data and forward that upstream data over the fiber leg using a binary modulated optical signal.

A method for low-rate signal transmission on Optical Transport Networks is provided. In the method, a signal is mapped to a low-rate OPU of a low-rate ODU, wherein the low-rate ODU comprises an ODU overhead section and the low-rate OPU, the low-rate OPU comprises an OPU overhead section and an OPU payload section, the low-rate ODU has a bit rate of 1, 244, 160 Kbps±20 ppm, and the OPU payload section has a bit rate of 1, 238, 954.31 Kbps±20 ppm; OPU overhead bytes and ODU overhead bytes are added to corresponding overhead section; then, the low-rate ODU is multiplexed to an Optical channel Data Unit-k (ODUk) that has a bit rate higher than the bit rate of the low-rate ODU; finally, the ODUk is transmitted via the OTN.

Optical network systems and components are disclosed, including a transmitter comprising a digital signal processor that receives data; circuitry that generate a plurality of electrical signals based on the data; a plurality of filters, each of which receiving a corresponding one of the plurality of electrical signals, a plurality of roll-off factors being associated with a respective one of the plurality of filters; a plurality of DACs that receive outputs from the digital signal processor, the outputs being indicative of outputs from the plurality of filters; a laser that supplies light; and a modulator that receives the light and outputs from the DACs, and supplies a plurality of optical subcarriers based on the outputs, such that one of the optical subcarriers has a frequency bandwidth that is wider than remaining ones of the optical subcarriers, said one of the optical subcarriers carrying information for clock recovery.

This disclosure relates to wavelength division multiplexed (WDM) passive optical networks (PON), and the transmission of point-to-point and broadcast or multicast channels from an optical line transmitter (OLT) to an optical network unit (ONU). There is provided a WDM PON (100) comprising: an OLT (105) coupled to a plurality of ONU (110a, 110b) using an optical fiber network (160); the OLT (105) having one or more WDM transceivers (115a, 115b) each arranged to receive multi-cast and point-to-point channels and wherein the or each WDM transceiver (115a, 115b) is arranged to transmit a said channel to a respective said ONU (110a, 110b) using a respective dedicated wavelength (λa, λb); an input channel switch (130a, 130b) associated with the or each WDM transceiver (115a, 115b) and arranged to selectively couple the input of the WDM transceiver to the multi-cast channels and the point-to-point channels (140,135); wherein the selected multi-cast or point-to-point channels are directly converted to the respective dedicated wavelength.