In the case of a OXC device having a route & select-type configuration of the conventional technique, when the port number is 20, then the entire device requires 120 WSSs having a 19 configuration. In the case of a route & select-type OXC device having ports more than 20 ports, a large amount of expensive WSSs is required. Thus, such a device is impractical from the viewpoint of cost. Thus, the expansion depending on an increase of traffic at nodes was impossible, flexible scalability could not be provided, and a reasonable network operation from the viewpoint of economy was difficult. According to the OXC device of this disclosure, regardless of the input port number and the output port number of the device, WSSs having a smaller scale than the conventional technique are used and the WSSs are internally-connected from a viewpoint different from that of the conventional technique, thus providing the device having a significantly-reduced cost.

Optical networks, nodes and methods are disclosed. To solve the aggressor issue and to reduce the cross-talk caused by the aggressors in colorless, directionless and contentionless reconfigurable optical add drop multiplexer nodes, the present disclosure configures a first broadcast module to supply only non-adjacent wavelengths to a first input port of a wavelength selective switch, and a second broadcast module to supply only non-adjacent wavelengths to a second input port of the wavelength selective switch.

A network is provided with a plurality of nodes connected to one another. At least one node of the plurality of nodes include one or more transponders. For example, the transponders may be configured to receive optical signals having a first set of wavelengths at a first degree of a plurality of degrees in the at least one node. The transponders may convert the received optical signals into electrical signals, and then regenerate optical signals by generating, based on the electrical signals, optical signals having a second set of wavelengths. The node may further include one or more switches configured to route the regenerated optical signals to one or more of the plurality of degrees of the at least one node.

A reconfigurable optical add/drop multiplexer (ROADM) complex in an optical network may include one or more core ROADM devices, each including multiple input/output port pairs configured for respective wavelengths or wavelength bands to be coupled to a fiber distribution panel (FDP) over fiber. The FDP may include multiple FDP connectors to receive optical signals from the core ROADM device(s) and may extract and route optical signals having a single wavelength to respective transponder connectors of the FDP for coupling to a transponder. Multiple expansion options may be enabled at the FDP. For example, according to one option, a single expansion connector may be enabled for coupling to an expansion device to provide additional drop port capacity. In another example, multiple expansion connectors may be enabled for coupling to respective expansion devices.

In some embodiments, an apparatus includes a reconfigurable optical add-drop multiplexer (ROADM). The ROADM has a wavelength selective switch (WSS) that does not perform power equalization when the WSS is operative. The ROADM also has a first pre-amplifier, a first channel power equalizer operatively coupled to the first pre-amplifier, a second pre-amplifier operatively coupled to the first channel power equalizer and the WSS, a first post-amplifier operatively coupled to the WSS, a second channel power equalizer operatively coupled to the first post-amplifier, and a second post-amplifier operative coupled to the second channel power equalizer.

Systems and methods for performing connectivity verification testing and topology discovery in a reconfigurable optical add/drop multiplexer (ROADM) are provided. The ROADM can include a ROADM block having a plurality of internal ports connected to a fiber shuffle via respective optical fibers. The ROADM block includes a test signal transmitter configured to inject an outgoing test signal having a unique signature into each internal port. The outgoing test signals are out-of-band of optical data signals traversing the ROADM. The ROADM block includes a test signal monitor configured to monitor for incoming test signals at each of the internal ports. The test signal monitor is configured to validate, based on a signature of an incoming test signal received at an internal port of the ROADM block, whether a valid connection exists between the internal port and an internal port of a second ROADM block.

An optical device may include a monolithic beam steering engine. The device may include a twin MN wavelength selective switch (WSS) including a first MN WSS and a second MN WSS. The first MN WSS may include a first panel section of the monolithic beam steering engine to perform first beam steering of first beams, wherein the first beam steering is add/drop port beam steering; and a second panel section of the monolithic beam steering engine to perform second beam steering of second beams, wherein the second beam steering is common port beam steering. The first MN WSS may include a first optical element aligned to the monolithic beam steering engine to direct one of the first beams or the second beams relative to the other of the first beams or the second beams, such that the first beams are directed in a different direction from the second beams.

Methods and apparatus are provided for switching an optical signal. In one aspect, an optical switching apparatus comprises a first beam splitting apparatus configured to split a first optical input signal into first and second optical signals, wherein the first optical signal has substantially the same polarization state as the second optical signal. The apparatus also comprises a switching matrix comprising a plurality of first outputs of the switching matrix and a plurality of second outputs of the switching matrix, each first output of the switching matrix associated with a respective one of the second outputs of the switching matrix, the switching matrix configured to selectively direct the first optical signal to a selected one of the first outputs of the switching matrix and to selectively direct the second optical signal to the second output of the switching matrix associated with the selected first output of the switching matrix. The apparatus further comprises a plurality of beam combining apparatus, each beam combining apparatus configured to combine optical signals from a respective one of the first outputs of the switching matrix and its associated second output of the switching matrix.

The present disclosure relates to a technical field of optical communication, and more particularly to a device and method for matching optical fiber connections for ROADM service side, wherein the device comprises a reference control optical channel transmitter, a downlink WSS, a plurality of emitting ports, a reference control optical channel receiver, an uplink WSS and a plurality of receiving ports; the reference control optical channel transmitter emitting a reference control optical channel signal, and the downlink WSS emitting the reference control optical channel through the respective emitting ports in a polling manner; the reference control optical channel receiver receiving the reference control optical channel signal, and the uplink WSS selectively receiving the reference control optical channel over the plurality of receiving ports in the polling manner; wherein the reference control optical channel operating within an operating wavelength range of WSSs in the ROADM but outside a wavelength range of a service optical channel. By using WSS to control polling of the reference control optical channel among service side ports of ROADM, the present disclosure realizes an auto-routing matching of an optical fiber connection between different service side ports of ROADM and improves configuration efficiency, and at the same time, also realize to monitor performance of the optical fiber connection between service side ports of ROADMs in different directions and be a standby physical channel for chassis cascade.

A Reconfigurable Optical Add/Drop Multiplexer (ROADM) node with a Colorless, Directionless, and Contentionless (CDC) architecture, targeting smaller degree nodes, includes an integrated ROADM degree and add/drop module having M common input and output ports and N add/drop input and output ports, wherein the integrated ROADM degree and add/drop module is formed by an MN demultiplexer Contentionless Wavelength Selective Switch (CWSS) and an MN multiplexer CWSS; and X degree modules, each having an input and output port connected to common ports of the integrated ROADM degree and add/drop module, a first set of ports of the N add/drop input and output ports are connected for degree-to-degree connectivity and a second set of ports of the N add/drop input and output ports are utilized for local add/drop, such that the integrated module provides both the degree-to-degree connectivity and the local add/drop.