An optical circuit switching matrix includes a plurality of optical ports, each optical port being optically coupled to a respective one of a plurality of user nodes and an optical coupler having at least one input port optically coupled to the plurality of optical ports, and an output port. The optical circuit switching matrix also includes a wavelength demultiplexer having an input optically coupled to the output port of the optical coupler, and a plurality of output ports, each output port being optically coupled to a respective one of the plurality of optical ports.

A photonic cross-connect arrangement is presented which is able to cope with the transmission of super-channels, wherein complete super-channels are dropped and added to change a direction of transport. At least a cyclic filter is used in a drop-branch of a cross-connect for dividing a super-channel into sub-channels and/or at least a further cyclic filter is used in an add-branch to configure a super-channel.

Components of an optical communications network are described at a node of the network providing switching from one or more degrees of received optical signal routed to a plurality of receivers. The switch at the node generally includes a passive reconfigurable optical add drop multiplexer (ROADM) having drop or output ports that connector to optical channels leading to optical receivers without optical amplifiers between the ROADM outputs and the receivers. Configurations of the node and corresponding parameters are described that provide for use of lower cost components due to the absence of an array of optical amplifiers connected to the ROADM outputs.

A method may include transmitting, by an optical device, a first channel. The first channel may have a first set of subcarriers. The first channel may be attenuated during transmission by a filter associated with a wavelength selective switch. The method may further include transmitting, by the optical device, a second channel. The second channel may have a second set of subcarriers. The second channel may be attenuated during transmission by the filter associated with the wavelength selective switch. The first channel and the second channel being included in a super-channel. The first set of subcarriers may be selected based on a first signal quality factor associated with attenuation of the first set of subcarriers by the filter. The second set of subcarriers may be selected based on a second signal quality factor associated with attenuation of the second set of subcarriers by the filter.

Consistent with the present disclosure, an optical switch is provided that switches multiple wavelength division multiplexed (WDM) optical signals. Each of the WDM signals includes optical signals having the same wavelengths. The WDM signals are supplied to optical splitters, which supply power split portions of the WDM signals to corresponding optical gates. Groups of the optical gates are associated with a corresponding switching block, which may include a cyclical arrayed waveguide grating (AWG), and the optical gates within each group are controlled so that one gate passes a received WDM signal portion while the remaining optical gates in the group are in a blocking configuration. As a result, the WDM portion received by the non-blocking gate is demultiplexed in the switching block and each of the wavelength components that constitute the selected WDM portion are supplied to corresponding outputs within the switching block. In a later time interval, a different optical gate may be rendered non-blocking so that a different WDM signal portion, supplied from a different optical splitter and carrying different information over the same wavelengths, may be input to the switching block. Thus, by controlling the optical gates, different WDM signal portions may be switched to, and thus demultiplexed by, a particular switching block. In addition, portions of the same WDM signal may be selectively supplied to different AWGs by appropriately control of the optical gates.

An approach to proving a flexible grid architecture for time and wavelength division multiplexed passive optical networks is described. One embodiment includes an optical transmitter array configured to transmit an optical signal, an optical combiner coupled to the optical transmitter array configured to receive unlocked wavelengths from the optical transmitter array and output a single optical signal, and an optical amplifier coupled to the optical combiner configured to boost downstream optical power. In some embodiments, a WDM filter is coupled to the optical amplifier, and a tunable optical network unit (ONU) coupled to the WDM filter is configured to transmit and receive the optical signals. In still other embodiments, a cyclic demultiplexer is coupled to the optical splitter and connects to an optical receiver array configured to receive optical signals.

An optical add/drop multiplexer branching apparatus is provided in the embodiments of the present invention, where the optical add/drop multiplexer branching unit includes: a trunk input end, a branch input end, a trunk output end, a branch output end, an optical add/drop multiplexer, a first coupler, a first detection circuit, and a control circuit, where the optical add/drop multiplexer includes an optical switch. A detection circuit detects whether a fault occurs in a trunk, and in a case in which a fault occurs in the trunk, a working mode is switched from a first working mode to a second working mode, to implement automatic redundancy on the trunk and ensure normal communication on a branch.

A state of polarization (SOP) controller allows a randomly polarized input beam to be converted to a single linear polarization, while transferring substantially all of the power to the output. The input beam is split into orthogonal components and one of the components rotated and a phase difference between the components compensated for. The phase aligned components may then be recombined into a single output. The phase shifters may be reset during a reset period during which the impact on data transmission is reduced.

A PON system comprising multiple PONs, each having a respective intelligent splitter monitor (ISM). In addition to having a passive optical splitter therein, an ISM also has several remotely powered active components configured to monitor the presence of uplink light signals on the ports of the splitter and communicate with the central office using out-of-band optical signals. These ISM functionalities enable the network operator, e.g., to automatically map PON connectivity, pairing each port on the splitter with a distinct optical network unit. The PON system further comprises an optical module connected to the multiple PONs through an optical switch in a manner that supports shared access to said module by the corresponding multiple ISMs. In an example embodiment, the optical module comprises an optical transceiver capable of communicating with the ISM transceivers and one or more lasers configured to provide high-intensity light for remotely charging the ISM batteries.

Waveguide shuffle blocks (WSBs) are provided that may incorporate waveguides routed in any pattern to effectuate many-to-many connectivity between optical cables/fibers or other WSBs connected thereto. Such WSBs may be configured in ways that allow the WSBs to be stacked and to achieve effective optical cable/fiber organization. Moreover, such WSBs may include readable tags that can provide information regarding a particular WSB configuration and/or what optical cables/fibers are connected so that network topology can be discovered and monitored. Some WSBs may be configured as wavelength shifting shuffles (WSSs) that allow a particular wavelength(s) of an optical signal(s) to be routed as desired and/or alter a first wavelength associated with a particular optical signal to a second wavelength. In other embodiments WSSs can be configured to allow for wavelength multiplexing/demultiplexing.