Aspects of the subject disclosure may include, for example, receiving a first optical signal from a first optical network via a first port of the wavelength converter, receiving a second optical signal from a second optical network via a second port of the wavelength converter, modulating the first optical signal with the second light signal to generate a third optical signal, eliminating the first light signal from the third optical signal to generate a fourth optical signal, and transmitting the fourth optical signal through the second optical network. The first optical signal can include a first digital signal modulated onto a first light signal of a first wavelength, the second optical signal can include a second light signal can include a second wavelength different from the first wavelength, and the fourth optical signal can include the first digital signal modulated onto the second light signal. Other embodiments are disclosed.

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.

A system for interconnecting a plurality of computing nodes includes a plurality of optical circuit switches and a plurality of electrical circuit switches. A first network stage comprises a first plurality of circuit switches selected from among the plurality of optical circuit switches and the plurality of electrical circuit switches. Each computing node among the plurality of computing nodes is optically coupled to at least one of the first plurality of circuit switches. A second network stage comprises a second plurality of circuit switches selected from among the plurality of optical circuit switches and the plurality of electrical circuit switches. Each circuit switch among the first plurality of circuit switches is optically coupled to each circuit switch among the second plurality of optical circuit switches.

Aspects of the subject disclosure may include, for example, receiving a first optical signal from a first optical network via a first port of the wavelength converter, receiving a second optical signal from a second optical network via a second port of the wavelength converter, modulating the first optical signal with the second light signal to generate a third optical signal, eliminating the first light signal from the third optical signal to generate a fourth optical signal, and transmitting the fourth optical signal through the second optical network. The first optical signal can include a first digital signal modulated onto a first light signal of a first wavelength, the second optical signal can include a second light signal can include a second wavelength different from the first wavelength, and the fourth optical signal can include the first digital signal modulated onto the second light signal. Other embodiments are disclosed.

An optical antenna may permit a duplex link formed by a transmit, Tx, beam towards a partner optical antenna and a receive, Rx, beam from the partner antenna. The antenna includes: a proximal path including a bidirectional waveguide for duplex propagation of the duplex link from a Tx source of the Tx beam and towards a receiver of the Rx beam; a distal path for a duplex propagation of the duplex link from/towards the partner optical antenna; a beam shaper positioned in the distal path to shape a duplex propagation pattern of the duplex link; and a controller controlling the beam shaper to adaptively shape the propagation pattern to enclose: a first position of the partner antenna at the transmission of the Rx beam; and a second of the partner antenna at the reception of the Tx beam.

A digital signal processing, DSP, unit (10) for use in a coherent optical receiver for an optical communications network. The DSP unit comprises an adaptive equaliser (12) and a processing block (22). The equaliser (12) comprises input ports for receiving electrical signals, each corresponding to a different state of polarization of an optical signal received by the coherent optical receiver,and output ports,each connected to a processing branch (14). A processing branch comprises a symbol sequence estimator, SSE, (16) and a carrier phase estimator, CPE, (18) comprising an input for receiving signal taped from an output of the processing branch. An output of the CPE is connected to a phase adjuster (20) interconnecting the respective output port of the equaliser and the SSE. The processing block (22) is connected to an output of the CPE,an output of the processing branch and at least one of the output of the phase adjuster and the outputs of the equalizer.

An apparatus includes an input port group, which includes multiple input slots, and multiple input ports are provided in each input slot. An input allocation matrix includes multiple first optical switches, and an input port of the first optical switch is connected to an input port of the input slot. A cross-connect matrix includes multiple second optical switches, and an output port of the first optical switch is connected to an input port of the second optical switch. An output allocation matrix includes multiple third optical switches, and an input port of the third optical switch is connected to an output port of the second optical switch. An output port group includes multiple output slots, multiple output ports are provided in each output slot, and an output port of the output slot is connected to an output port of the third optical switch.

An optoelectronic switch for switching a signal from an input device to an output device includes a plurality of switch modules, each connected or connectable to an optical interconnecting region, wherein: each switch module is configured to output a WDM output signal to the optical interconnecting region, and the optoelectronic switch further includes one or more MZI routers, each configured to direct the WDM output signal from its source switch module towards its destination switch module, wherein the one or more MZI routers are located either on each of the switch modules, or in the interconnecting region.

A fast optical switch can be fabricated/constructed, when vanadium dioxide (VO.sub.2) ultra thin-film or a cluster of vanadium dioxide particles (less than 0.5 microns in diameter) embedded in an ultra thin-film of a polymeric material or in a mesh of metal nanowires is activated by either an electrical pulse (a voltage pulse or a current pulse) or a light pulse just to induce rapid insulator-to-metal phase transition (IMT) in vanadium dioxide ultra thin-film or vanadium dioxide particles embedded in an ultra thin-film of a polymeric material or in a mesh of metal nanowires. The applications of such a fast optical switch for an on-Demand optical add-drop subsystem, integrating with or without a wavelength converter are also described.

The embodiments disclosed herein provide fast recovery of a network signal path by, in the event of a failure or unacceptable degradation in a signal in the original network path, diverting the optical signal passing through the network to a preselected bypass optical path which is maintained in a warm or operational state. The optical elements on the bypass optical path are available network resources which may, during part or all of the time the bypass path is designated for a node in the primary optical path, be in use to transmit other optical signals in the network. By maintaining the resources in the designated bypass path in a warm or operating state, fast rerouting and recovery of an interrupted signal is possible.