Disclosed herein is wavelength-division multiplexer with an internal optical signal tuned by a mounted signal pitch router. In particular, disclosed is a wavelength-division multiplexing (WDM) optical assembly including an optical signal router, a WDM filter, and a signal pitch router. The WDM filter has a wavelength selective surface positioned proximate the second side of the optical signal router. The signal pitch router has a transmissive surface positioned proximate to a side of the optical signal router, and a second reflective surface opposite the transmissive surface. A depth of the signal pitch router establishes and tunes a pitch of a routing optical path within the optical signal router. This provides for easier, faster, more reliable, and more cost effective manufacturing and assembly of the WDM optical assembly.

A photonic integrated circuit includes a main light source, a redundant light source, a controller, an optical switch, and a modulator. The main light source outputs main light through a main light input waveguide. The redundant light source outputs redundant light through a redundant light transmission waveguide. The controller generates a first switch signal based on a fault state of the main light source. The optical switch selectively provides the redundant light from the redundant light transmission waveguide to a redundant light input waveguide based on the first switch signal. The modulator modulates main light from the main light input waveguide or redundant light from the redundant light input waveguide and outputs a first optical signal.

A method for generating a customized WRONoC topology is proposed, which is executed by a computer, the method comprising using the computer to perform the following: providing design rules, design specs and a pre-assignment netlist; performing a topology initialization which an initial topology with a minimum number of MRRs is generated according to the netlist; performing a critical path-aware SA optimization to optimize the topology; and performing a wavelength assignment such that the wavelength used by each signal is determined.

A multiport optical switch is used to controllably select a specific incoming optical signal that is to be processed by an associated optical channel monitor (OCM). The OCM includes a tunable optical filter and photodetector arrangement, and is configured to measure the optical spectrum of the incoming optical signal and extract information associated with the various optical channels forming the incoming optical signal (i.e., power, wavelength, OSNR, etc., per channel in the signal). The OCM also includes a processor that generates a pair of output control signals, a first signal to control the wavelength scanning process of the tunable optical filter and a second signal to control the setting of the multiport optical switch. The second signal may also be used to perform detuning of a selected input of the multiport optical switch, providing the ability to adjust the power level of an input signal prior to entering the OCM.

The present application discloses example optical transmission apparatuses, where one example apparatus includes a filter, a router, and an optical multiplexer. The filter is connected to the router, and the router is connected to the optical multiplexer. The filter performs parity optical demultiplexing on 2N input optical signal groups by using 2N comb filters to obtain 2N odd optical signal groups and 2N even optical signal groups, and sends the 2N odd optical signal groups and the 2N even optical signal groups to the router. The router separately routes the 2N odd optical signal groups and the 2N even optical signal groups to the optical multiplexer by using at least four AWGRs. The optical multiplexer performs, by using 2N optical multiplexers, optical multiplexing on 4N optical signal groups output by the router to obtain 2N output optical signal groups.

A method and system for multi-channel optical XPM compensation may include a DCM to improve performance of a feed-forward control loop in an optical path in an optical network. Additionally, various spectral overlap schemes may be used with multi-channel WDM optical signals using XPM compensators in parallel, such as at a ROADM node. Polarization diversity may also be supported for XPM compensation including a DCM.

A device may comprise a first portion and a second portion. The first portion may comprise a plurality of slots configured to receive a plurality of fiber optic cables. Each fiber optic cable may be received in a respective slot of the plurality of slots. The second portion may comprise a plurality of protruding members configured to bend the plurality of fiber optic cables, received in the first portion, to cause the plurality of fiber optic cables to emit light. The second portion may further comprise the light detection unit. The light detection unit may be configured to determine whether light emitted by a fiber optic cable is detected; and provide an indication regarding a port of the plurality of ports based on determining that the light, emitted by the fiber optic cable, is detected. The fiber optic cable may be connected to the port.

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

The present application discloses example optical transmission apparatuses, where one example apparatus includes a filter, a router, and an optical multiplexer. The filter is connected to the router, and the router is connected to the optical multiplexer. The filter performs parity optical demultiplexing on 2N input optical signal groups by using 2N comb filters to obtain 2N odd optical signal groups and 2N even optical signal groups, and sends the 2N odd optical signal groups and the 2N even optical signal groups to the router. The router separately routes the 2N odd optical signal groups and the 2N even optical signal groups to the optical multiplexer by using at least four AWGRs. The optical multiplexer performs, by using 2N optical multiplexers, optical multiplexing on 4N optical signal groups output by the router to obtain 2N output optical signal groups.

A method and system for selective and per-node XPM compensation may separate wavelengths into short traveling wavelengths (STW) and long traveling wavelengths (LTW) based on transmission distance over their respective optical paths. XPM compensation at ROADM nodes may be selectively performed for the LTW, while the STW may be passed through without XPM compensation, among other functionality at the ROADM nodes.