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.

An OLT configures combinations of wavelength pairs used for upstream and downstream signals, in a wavelength multiplexing optical communication system which performs single-core bidirectional transmission of a plurality of upstream and downstream signals, in such a way that the maximum value of the chromatic dispersion delay amount calculated from each wavelength pair is less than the maximum value of the chromatic dispersion delay amounts calculated when the combinations of wavelength pairs used for upstream and downstream signals are both allocated from the short wave side.

A method of establishing communication between an optical line terminal and an optical network unit within an optical access network includes receiving a signal indication from an optical transceiver of an optical line terminal. The signal indication includes: (i) a loss-of-signal indication indicating non-receipt of an upstream optical signal from the optical network unit; or (ii) a signal-received indication indicating receipt of the upstream optical signal from the optical network unit. The method includes determining whether the signal indication includes the loss-of-signal indication. When the signal indication includes the loss-of-signal indication, the method includes instructing the optical transceiver to cease signal transmission from the optical transceiver to the optical network unit. Moreover, when the signal indication includes the signal-received indication, the method includes instructing the optical transceiver to transmit a downstream optical signal from the optical transceiver to the optical network unit.

Optical fiber-based wireless systems and related components and methods are disclosed. The systems support radio frequency (RF) communications with clients over optical fiber, including Radio-over-Fiber (RoF) communications. The systems may be provided as part of an indoor distributed antenna system (IDAS) to provide wireless communication services to clients inside a building or other facility. The systems incorporate various functions, such as optical network terminal (ONT), splitter, and local powering, in antenna coverage areas.

A network component comprising at least one processor configured to implement a method comprising collecting wavelength availability information associated with a wavelength switched optical network (WSON), receiving a path computation request to transport a signal through the WSON, calculating at least one route through the WSON for the signal, and assigning at least one wavelength for the signal to use along the route. Also disclosed is a network comprising a first path computation element (PCE) configured to compute at least one route for a signal between a source and a destination, and a second PCE in communication with the first PCE, wherein the second PCE is configured to receive the route from the first PCE and assign at least one wavelength to the route.

There is disclosed in one example a fiberoptic communication circuit for wavelength division multiplexing (WDM) communication, including: an incoming waveguide to receive an incoming WDM laser pulse; an intermediate slab including a demultiplexer circuit to isolate n discrete modes from the incoming WDM laser pulse; n outgoing waveguides to receive the n discrete modes, the outgoing waveguides including fully-etched rib-to-channel waveguides; and an array of n photodetectors to detect the n discrete modes.

Embodiments of the present invention disclose a wavelength shift control method and system, to implement stable control over temperature of a laser to ensure that a transmit wavelength of the laser is stable in a burst work process of a transmitter and is not shifted to avoid impact on normal work of a PON system with a plurality of wavelength paths. The method includes: generating a burst control signal; sending the burst control signal to a controller; and controlling switch statuses of a laser and a heater according to the received burst control signal, where when a switch of the laser is in an on state, a switch of the heater is in an off state, and when a switch of the laser is in an off state, a switch of the heater is in an on state, so that a temperature of the laser remains stable.

A method of establishing communication between an optical line terminal and an optical network unit within an optical access network includes receiving a signal indication from an optical transceiver of an optical line terminal. The signal indication includes: (i) a loss-of-signal indication indicating non-receipt of an upstream optical signal from the optical network unit; or (ii) a signal-received indication indicating receipt of the upstream optical signal from the optical network unit. The method includes determining whether the signal indication includes the loss-of-signal indication. When the signal indication includes the loss-of-signal indication, the method includes instructing the optical transceiver to cease signal transmission from the optical transceiver to the optical network unit. Moreover, when the signal indication includes the signal-received indication, the method includes instructing the optical transceiver to transmit a downstream optical signal from the optical transceiver to the optical network unit.

A coaxial transmitter optical subassembly (TOSA) including a cuboid type TO laser package may be used in an optical transceiver for transmitting an optical signal at a channel wavelength. The cuboid type TO laser package is made of a thermally conductive material and has substantially flat outer surfaces that may be thermally coupled to substantially flat outer surfaces on a transceiver housing and/or on other cuboid type TO laser packages. An optical transceiver may include multiple coaxial TOSAs with the cuboid type TO laser packages stacked in the transceiver housing. The cuboid type TO laser package may thus provide improved thermal characteristics and a reduced size within the optical transceiver.

A method of modulation implemented by a polarization insensitive integrated optical modulator (PIIOM). The method includes receiving, at an input, a continuous wave (CW) light, splitting, by a first polarization splitter-rotator (PSR), the CW light into a first light beam having a transverse electric (TE) polarization and a second light beam having a transverse magnetic (TM) polarization, rotating, by the first PSR, the second light beam having the TM polarization to generate a third light beam having the TE polarization, modulating, with a multiport modulator, the first light beam with data to generate a first output signal and the third light beam with data to generate a second output signal, combining, by a second PSR, the first output signal and the second output signal to form a modulated output CW light, and transmitting, at an output separate from the input, the modulated output CW light to an optical receiving device.