Example optical signal processing apparatuses and methods are provided. One example apparatus includes: N light sources, a wavelength multiplexer, an optical processor, a dither application circuit, a first detection circuit, a second detection circuit, and a feedback control circuit. The light source generates a single-wavelength signal. The dither application circuit applies a dither signal to the light source. The wavelength multiplexer generates a multi-wavelength signal based on the single-wavelength signal. The first detection circuit is configured to obtain a first power signal of a signal input to the optical processor. The second detection circuit is configured to obtain a second power signal of a signal output from the optical processor. The feedback control circuit adjusts a working parameter of the optical processor based on the dither signal corresponding to the single-wavelength signal, the first power signal, and the second power signal.

Methods and systems for monitoring an optical network are described. An optical device may receive a data signal. The optical device may send the data signal to a test port. A measuring device may measure characteristics associated with the data signal.

The present invention includes novel techniques, apparatus, and systems for optical WDM communications. Tunable lasers are employed to generate respective subcarrier frequencies which represent subchannels of an ITU channel to which client signals can be mapped. In one embodiment, subchannels are polarization interleaved to reduce crosstalk. In another embodiment, polarization multiplexing is used to increase the spectral density. Client circuits can be divided and combined with one another before being mapped, independent of one another, to individual subchannels within and across ITU channels. A crosspoint switch can be used to control the client to subchannel mapping, thereby enabling subchannel protection switching and hitless wavelength switching. Network architectures and subchannel transponders, muxponders and crossponders are disclosed, and techniques are employed (at the subchannel level/layer), to facilitate the desired optical routing, switching, concatenation and protection of the client circuits mapped to these subchannels across the nodes of a WDM network.

An approach for realizing low-power, high-port-count optical switching systems, such as OXCs, WXCs, and ROADMs is presented. Optical switching systems in accordance with the present disclosure include arrangements of frequency-filter blocks, each of which includes a cascaded arrangement of tunable couplers and tunable Mach-Zehnder Interferometers (MZIs) that provides a substantially flat-top broadband transfer function for the frequency-filter block. The tunability for these devices is achieved by operatively coupling a low-power-dissipation phase controller, such as a stress-optic phase controller or liquid-crystal-based phase controller with one arm of the device, thereby enabling control over the coupling coefficient of the device.

Implementations described and claimed herein provide systems and methods for a configurable optical peering fabric to dynamically create a connection between participant sites without any physical site limitations or necessity of specialized client and network provider equipment being located within such a facility. Client sites to a network may connect to a configurable switching element to be interconnected to other client sites in response to a request to connect the first client site with a second site, also connected to network, via the switching element. A request may trigger verification of the requested and, upon validation, transmission of an instruction to the switching element to enable the cross connect within the switching element. The first site and the second site may thus be interconnected via the switching element in response to the request, without the need to co-locate equipment or to manually install a jumper between client equipment.

A method for low-rate signal transmission on Optical Transport Networks is provided. In the method, a signal is mapped to a low-rate OPU of a low-rate ODU, wherein the low-rate ODU comprises an ODU overhead section and the low-rate OPU, the low-rate OPU comprises an OPU overhead section and an OPU payload section, the low-rate ODU has a bit rate of 1, 244, 160 Kbps±20 ppm, and the OPU payload section has a bit rate of 1, 238, 954.31 Kbps±20 ppm; OPU overhead bytes and ODU overhead bytes are added to corresponding overhead section; then, the low-rate ODU is multiplexed to an Optical channel Data Unit-k (ODUk) that has a bit rate higher than the bit rate of the low-rate ODU; finally, the ODUk is transmitted via the OTN.

A telecommunications module includes an optical wavelength division multiplexer/demultiplexer configured to demultiplex a first optical signal input into the telecommunications module into a plurality of different wavelengths, a fiber optic splitter configured to split a second optical signal input into the telecommunication module into a plurality of optical signals, and a plurality of optical add/drop filters, each of the optical add/drop filters configured to combine one of the optical signals that has been split by the fiber optic splitter and one of the wavelengths that has been demultiplexed by the optical wavelength division multiplexer/demultiplexer into a combination output signal that is output from the telecommunications module.

An integrated connector-wavelength division multiplexing (WDM) device includes a housing defining a housing interior and a connector interface having at least one ferrule, a device input optical fiber extending from the housing to carry an input optical beam, a device output optical fiber extending from the housing to carry an output optical beam, and a plurality of channel filters positioned in the housing interior. A first channel filter is connected to the input optical fiber and a second channel filter is connected to the output optical fiber, wherein each of the plurality of channel filters is configured to separate at least one optical signal from a plurality of optical signals of the input optical beam and provide the at least one optical signal to the at least one ferrule. A fiber optic module or submodule having one or more integrated connector-WDM devices is also disclosed.

A method for all-optical reduction of inter-channel crosstalk for spectrally overlapped optical signals for maximizing utilization of an available spectrum includes receiving a plurality of spectrally overlapped optical signals modulated with data. The method further includes generating conjugate copies of each of the plurality of optical signals using non-linear optics. The method further includes selecting the conjugate copies and adjusting an amplitude, a phase, and a delay of the conjugate copies. The method further includes performing inter-channel interference (ICI) compensation on the spectrally overlapped optical signals in an optical domain by adding the adjusted conjugate copies to the spectrally overlapped optical signals.

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.