Abstract: A data center network and a method for deploying the data center network. The data center network includes one core switch group, m cyclic arrayed waveguide grating (CAWG) groups, and m edge switch groups, where the core switch group includes k core switches; each CAWG group includes 2*Y N*N CAWGs, where the 2*Y CAWGs include Y uplink CAWGs and Y downlink CAWGs, the Y uplink CAWGs are connected to each core switch in the core switch group separately using an optical uplink, and the Y downlink CAWGs are connected to each core switch in the core switch group separately using an optical downlink; and each edge switch of an edge switch group is connected to an uplink CAWG and a downlink CAWG in a corresponding CAWG group separately. The present invention can reduce the number of optical fibers in a data center network.

Abstract: A method of communication through a network, executed by a communication apparatus that performs transmission by selecting a transmission mode, the method includes determining whether to transmit the data in either a first mode or a second mode when transmitting data; transmitting the data using a predetermined number of kinds of optical signals having different levels in light intensity when determined to transmit in the first mode; and transmitting the data using a fewer number of kinds of optical signals having different levels in light intensity than the predetermined number when determined to transmit in the second mode.

Abstract: An optical communications method and an optical communications apparatus are provided. The method is executed on a communications node that includes an input optical modulator array and an output optical modulator array. The input optical modulator array includes N input optical modulators. The method includes determining at least two local input areas from the input optical modulator array, so that each input optical modulator in each local input area is used to receive a foreign signal light. The method also includes determining at least two local output areas from the output optical modulator array. Each output optical modulator in each local output area is used to send the foreign signal light, and each input optical modulator in a local input area is capable of transmitting the signal light to each output optical modulator in a corresponding local output area.

Abstract: The present disclosure discusses an improved optical transceiver. The optical transceiver of the present disclosure includes an optical transmitter and an optical receiver coupled to an area of a printed circuit board that includes a plurality of thermal microvias. The thermal microvias are coupled to a heat sink or other heat dissipater and provide a path from the components of the optical transceiver to the heat dissipater for heat to travel.

Abstract: A node apparatus is installed at a node located on a route from a start node to an end node, and includes: a parameter calculating unit configured to, upon receiving routing information specifying the route and a first parameter representing an amount of signal degradation, update the first parameter by using a second parameter representing an amount of signal degradation along a transmission route to an adjacent node, and generate a third parameter representing an amount of signal degradation along a transmission route between the start node and the node, specified by the routing information; and a determination unit configured to determine reachability of the route specified by the routing information in accordance with the third parameter and a fourth parameter representing an amount of signal degradation along a transmission route from the node to the end node specified by the routing information.

Abstract: In one aspect, the present disclosure relates to a communications system which, in one embodiment, includes a phase-correlated, orthogonally-polarized, light-stream generator (POLG) for preparing light into phase coherent light streams having defined states of polarization and spectral composition. In one embodiment, the POLG includes a light source configured to emit light having a predetermined wavelength and a polarization apparatus configured to prepare light from the light source into particular states of polarization. The POLG also includes a phase modulator configured to produce light having a plurality of wavelengths and configured to retard the phase of propagation of light with a first state of linear polarization while not retarding the phase of light with a state of linear polarization orthogonal to the first state of linear polarization when an external electric field is applied.

Abstract: Methods and systems for optical path computation based on a reachability matrix may rely on matrix multiplication to determine a number and respective network locations of regenerators for establishing an end-to-end reachable path in an optical network between a source node and a destination node. The reachability matrix may specify directly reachable optical paths between nodes in the optical network.

Abstract: A device may receive optical network information associated with a plurality of super-channels. Each super-channel, of the plurality of super-channels, may include a plurality of optical channels transported as a single optical channel. The device may assign the plurality of super-channels to a plurality of sets of super-channels. The device may receive a request for a subset of the optical network information associated with a set of super-channels of the plurality of sets of super-channels. The device may provide, based on the request, information that identifies the subset of the optical network information associated with the set of super-channels via a user interface.

Abstract: An apparatus for measuring optical power including a first multiplexer/demultiplexer to split/combine an optical signal including a first wavelength and second wavelength; a second multiplexer/demultiplexer to split/combine an optical signal including the first wavelength and the second wavelength; a first tap photodetector coupled to the first and second multiplexer/demultiplexers and to a first measurement device; and a second tap photodetector coupled to the first and second multiplexer/demultiplexers and to a second measurement device.

Abstract: An optical communication system, a circuit, and a method of operating an optical communication system are provided. The optical communication system is disclosed to include a photodiode configured to receive optical signals and convert the received optical signals into electrical signals, a Trans-Impedance Amplifier (TIA) electrically connected with the photodiode such that the TIA receives the electrical signals from the photodiode and is configured to convert the electrical signals received from the photodiode into amplified electrical signals, and a feedback loop connected between an input of the TIA and an output of the TIA that includes a switchable capacitor bank connected thereto which introduces at least one zero into a feedback factor transfer function of the TIA thereby tuning out poles or equalizing delay introduced by a TIA input network connected between the photodiode and the input of the TIA.

Abstract: A method for transmitting electric power and signals between a wall and a leaf pivotally mounted on the wall includes transmitting the electric power so as to be galvanically isolated, and transmitting the signals optically or optoelectronically.

Abstract: An optical receiver includes closed-loop composite second order (CSO) distortion correction logic. An optical communication system includes a transmitter comprising open-loop composite second order (CSO) distortion correction logic, and a receiver comprising closed-loop composite second order (CSO) distortion correction logic.

Abstract: An apparatus for inline monitoring of transmit signals is disclosed. The apparatus includes a processor, and one or more fiber optic lines for supplying a transmit signal to/from a remote transmission station. The processor is configured to receive input for selecting one or more fiber optic lines for examination, determine at least one property of the transmit signal to be monitored, and retrieve information corresponding to the at least one property for a predetermined period of time. The processor is further configured to output a visual representation of the retrieved information, perform an analysis of the retrieved information and the visual representation, and facilitate identification of at least one status associated with the transmit signal based, at least in part, on the analysis.

Abstract: A signal monitoring device, a signal transmission/reception device and a communication device, which realize easy acquisition of a diagnosis result and a signal value, and further realize fast acquisition of the diagnosis result. A signal monitoring device includes: a difference value calculator that time-sequentially calculates, for a signal to be monitored, a difference value between a signal value thereof and a previously set threshold; and a storage that updates and stores the time-sequentially calculated difference value in accordance with a previously set rule.

Abstract: Provided is a frequency error estimating apparatus used for a coherent optical receiver, which determines an amplitude of a baseband digital electrical signal converted from a received light signal modulated with a phase and amplitude shift keying, determines, with respect to each determined amplitude, a modulated phase component of the baseband digital electrical signal based on phase noise estimation values and frequency error estimation values of N previous symbols (N is a positive integer), and calculates a frequency error based on an inter-symbol phase difference of a signal obtained by cancelling the modulated phase component from the baseband digital electrical signal.

Abstract: We describe a LCOS (liquid crystal on silicon) telecommunications light beam routing device, the device comprising: an optical input; a plurality of optical outputs; a LCOS spatial light modulator (SLM) in an optical path between said input and said output, for displaying a kinoform; a data processor, coupled to said SLM, configured to provide kinoform data for displaying said kinoform on said SLM; wherein said kinoform data defines a kinoform which routes a beam from said optical input to a selected said optical output; wherein said data processor is configured to input routing data defining said selected optical output and to calculate said kinoform data for routing said beam responsive to said routing data; and wherein said data processor is configured to calculate said kinoform data by: determining an initial phase pattern for said kinoform; calculating a replay field of said phase pattern; modifying an amplitude component of said replay field to represent a target replay field for said beam routing, reta

Abstract: A method of optical label swapping implemented by a switch used in a software defined network system that in one embodiment includes providing a 400-Gbit/s payload having a Nyquist shaped carrier in a 75-Ghz bandwidth spacing using a payload generator module controlling at least one first optical laser, and inserting a first optical label adjacent to the payload flow in a remainder of a 100-Ghz bandwidth with a label generator controlling at least one second optical laser. The label generator and the payload generator are controlled by a software defined network (SDN). A package of the payload and the first optical label is transmitted to a receiving node. The optical label can be swapped at the receiving node with a flex grid wavelength selective switch (WSS) controlled by the software defined network.

Abstract: An optical transmission device includes a receiver that receives first light, a transmitter that outputs second light, a memory, a processor coupled to the memory, configured to control a first optical level of the second light in such a way that a second optical level calculated based on an optical level of the received first light and an optical level of the second light that is output from the transmitter becomes a predetermined target value, a combiner that combines the received first light and the second light for which the first optical level is controlled by the processor, and an amplifier that amplifies the combined light.

Abstract: A method and system are provided for measuring the propagation time, or one-way delay or latency, of an 8B/10B data stream, such as a CPRI stream, through a network using a transport network protocol, such as OTN. Embodiments of the present disclosure do not modify the CPRI client and are unlimited in the amount of delay that can be measured. At first and second network endpoints, information is gathered related to patterns associated with successive occurrences of a control character in the 8B/10B encoded data stream. This information is sent over a side channel separate from the 8B/10B encoded data stream. The one-way delay is determined based on a difference between the information related to the pattern identified at the first and second network endpoints.

Abstract: An optical device incorporates into the same physical structure the functionality of two or more wavelength selective switches. The wavelength components associated with the first optical switch are isolated from the wavelength components associated with the second optical switch by their spatial displacement along one axis on a programmable optical phase modulator. Remaining crosstalk between the components is reduced by spatially separating the components of the two wavelength switches having the same wavelength along another axis of the programmable optical phase modulator.