Abstract: A data center for executing a data processing application includes processing units, sub-units or servers. Each of the processing units, sub-units or servers can execute a part or all of the data processing application. The processing units, sub-units or servers are electrical disjoint with respect to data communications, but can communicate with each other over free space optical links.

Abstract: A method of controlling consumer devices using an infrared dongle coupled to a mobile device includes receiving power for the infrared dongle from the mobile device. The infrared dongle includes an infrared transmitter coupled to a microcontroller. One or more instructions are received in the microcontroller from the mobile device. The received one or more instructions are generated from codes stored in a memory of the mobile device. In response to the receiving, one or more infrared signals are transmitted via the infrared transmitter to at least one of the consumer devices.

Abstract: A mechanism for an optical transceiver to log information about its operational parameters to an off transceiver host computing system (hereinafter referred to simply as a “host”). The optical transceiver may be communicatively coupled to the host. The optical transceiver is configured to identify operational information regarding itself. The operational information may include statistical data about operation, or may include measured parameters. The optical transceiver may log the information to the memory of the host in an off transceiver logging operation.

Abstract: An optical communication system for generating and transmitting a modulated optical signal in which light emitted by a light source is modulated by an optical modulator in accordance with an input electrical signal. A bias signal generator applies a bias electrical signal to bias the optical modulator at a bias angle away from quadrature. The bias signal generator monitors the input electrical signal and adjusts the applied bias electrical signal in dependence on the input electrical signal. The system further includes a receiver which may include an equalizer coupled to the photodetector of the receiver.

Abstract: Systems and methods of polarization demultiplexing are disclosed. One such method receives a transmitted polarization-multiplexed optical signal The polarization-multiplexed has multiple polarizations, each of which represents an independent data stream. The method converts the polarization-multiplexed optical signal to a corresponding polarization-multiplexed electrical signal. The method determines an inverse transformation matrix that meets an independent component analysis (ICA) criterion. The method applies the inverse transformation matrix to the polarization-multiplexed electrical signal, which produces a polarization-demultiplexed electrical signal. The method phase estimates the polarization-demultiplexed electrical signal to recover the data stream.

Abstract: The present invention utilizes external synchronization to generate a completely standardized or functionally standardized optical transmission unit of level k (OTUk[V]) signal providing less jitter and wander build-up through a network of optical transport network (OTN) elements. This increases noise margins of transported signals and payloads. The present invention provides stratum-level synchronization utilizing a standards-based approach. In one embodiment of the present invention, rate adapters are included to provide m/n scaling of OTUk[V] signals to rates common in SONET and SDH synchronizers to provide line and loop distribution of timing through OTUk[V] signals. The present invention provides a choice of external synchronization sources including building integrated timing source (BITS), line, and loop timing sources. In another exemplary embodiment, the present invention provides multiple external references and automated timing protection switching for redundancy and reliability.

Abstract: A method and apparatus for providing passive optical networks with extended reach and/or splitting ratio are disclosed. For example, the optical network comprises a first optical line termination (OLT) device having a transceiver for sending and receiving optical signals. The optical network further comprises an optical extender box comprising at least one hybrid SOA-Raman amplifier, wherein the optical extender box is coupled to the first optical line termination device via a first standard single mode fiber section. Finally, the optical network further comprises an optical splitter coupled to the optical extender box via a second standard single mode fiber section.

Abstract: A mechanism for adjusting or shutting off an optical signal within a network system is provided. The system may include a generating element for providing an optical signal and a bi-directional coupler for transmitting the optical signal to downstream components and fiber links and for transmitting a reflected optical signal based on the reflection characteristics of the downstream components to a converter element. The converter element converts the reflected optical signal to an electrical trigger signal that is used by a processing element to monitor the degradation or operational conditions within the network system. Based on the electrical trigger signal the processing element may adjust or shut off the optical signal at the generating element or at another element within the network system or another network system. The processing element may also send a communication signal to other elements or an operator to indicate unacceptable noise within the network system.

Abstract: For an optical network link, a receiving node monitors optical performance and upon determination of lowered optical performance for an extended period of time, the node can signal a transmitting node to lower bit transfer rate from a nominal bit transfer rate. The receiving node has a transponder which has a digital electronic variable bandwidth filter to process the digitized signals at the lowered bit transfer rate to increase the SNR of the signals. Optical performance of the link is optimized although at the lowered bit transfer rate.

Abstract: An optical apparatus includes a first optical amplifier for adjusting an output value to a constant level; an optical signal processor located before the first optical amplifier and processing the optical signal; a second optical amplifier located before the optical signal processor and subjected to automatic gain control for adjusting a gain constant; and a controller detecting a level of the optical signal at an output of the second optical amplifier. The controller adjusts a level of an output value of the first optical amplifier such that the level of the optical signal at the output of the second optical amplifier is held at the optimum value if the detected level of the optical signal differs from an optimum value, compensates for a loss caused in the optical signal processor and maintains the level of the optical signal at the output of the second optical amplifier at the optimum value.

Abstract: An optical communication system includes an optical transmission terminal including a first transmitter for transmitting an optical signal, and a second transmitter for transmitting information that indicates the first transmitter transmitting the optical signal; and an optical receiving terminal including an optical receiver for receiving the optical signal and the information transmitted from the first and second transmitter, respectively, a storage device for storing a power value of the optical signal monitored in response to receipt of the information transmitted from the second transmitter, and a fault detector for detecting fault of the optical signal by continuously monitoring a power value of the optical signal received by the optical receiver in comparison with the power value stored in the storage device.

Abstract: A quantum correlated photon pair generating device includes a nonlinear optical medium that generates quantum correlated photon pairs from excitation light by spontaneous parametric fluorescence and generates auxiliary idler light from the excitation light and auxiliary signal light by stimulated parametric conversion. The excitation light and auxiliary signal light are generated separately, combined, and input simultaneously to the nonlinear optical medium. An optical demultiplexer separates the auxiliary signal light and the auxiliary idler light output from the nonlinear optical medium. The intensities of the output auxiliary signal light and auxiliary idler light are detected, and the intensity or wavelength of the excitation light or the temperature of the nonlinear optical medium is controlled to maintain the ratio of the detected intensities at a preset value. The rate at which the quantum correlated photon pairs are generated is thereby held steady.

Abstract: A frequency converter includes a first direct digital synthesizer that receives a signal having a predetermined frequency f_master as a clock signal and further an internal frequency setting signal, and outputs an internal signal having a frequency based on the internal frequency setting signal, and a second direct digital synthesizer that receives the internal signal as a clock signal, and further an output frequency setting signal, and outputs an output signal having a frequency f_slave (=f_master??) based on the output frequency setting signal. A difference between the predetermined frequency f_master and the frequency of the internal signal is larger than a difference between the predetermined frequency f_master and the frequency f_slave of the output signal.

Abstract: The invention relates to an optical modulator control system implemented in an optical burst mode transmitter, said control system comprising means for measuring a plurality of optical power sample values and associated optical wavelength data values from a modulator at a first sampling rate, wherein an average power table is generated from said values for each sample period and stored in a memory. The control system also comprises means for performing a control error calculation from two or more stored average power tables at a second sampling rate to calculate a single error value to provide gain and/or bias control signals, wherein the second sample rate is sampled at a slower rate than the first sample rate. The control system described optimises the modulator performance over temperature and lifetime in an optical network.

Abstract: A reconfigurable optical add/drop multiplexer (ROADM) with a multiplexer, demultiplexer, and a wavelength cross-connect unit provides directionless capabilities. The ROADM allows a signal not to be limited to a particular direction when added at an optical network node, for example. The signal can be sent to other directions of the optical network node. Furthermore, the ROADM allows the wavelengths of add and drop signals to be changed and hence is “colorless.

Abstract: Methods, systems, and computer-readable media provide for notifying an optical line termination (OLT) of a power failure. According to embodiments, a method for notifying an OLT of a power failure is provided. According to the method, a notification of a power failure at an optical network termination (ONT) is received. In response to receiving the notification, power is retrieved from a dedicated power storage unit dedicated to providing power for the transmission of a dying gasp alarm. The dying gasp alarm is transmitted to the OLT utilizing at least a portion of the power from the dedicated power storage unit. The dying gasp alarm notifies the OLT of the power failure.

Abstract: In an optical communication network that includes a plurality of interconnected network nodes, a method includes storing in each network node one or more cross-talk margins of respective communication channels that traverse the node. A potential communication channel that traverses a subset of the nodes in the network is identified. A quality of the potential communication channel is evaluated by processing the cross-talk margins stored in the nodes in the subset.

Abstract: In an OTN (Optical Transport Network), an OTN interface of a network element may receive a BDI (Backwards Defect Indicator) signal from a far end network element to which OTN frames are being transmitted. A BDI signal indicates the occurrence of a unidirectional failure in the transmission of OTN frames to which the far end network element responds by switching its routing to the network element. The OTN interface generates an AIS (Alarm Indication Signal) for its network element so that the network element switches network communication channels to the far end network element to ensure bidirectional switching upon a unidirectional failure.

Abstract: An optical and/or optoelectrical transceiver and system are disclosed that enable parallel transmission of data and management signals via an optical fiber without affecting data signal transmissions transmitted on the optical fiber. Furthermore, the present transceiver and system provide a fault diagnosis function for an optical fiber link. The transceiver and system generally comprise an interface, an intersecting transmission management unit, a driver, a management signal driving unit, an optical transmitter, an optical receiver, an amplifier, a management signal recovery unit, a management unit, and optionally, a power supply unit.

Abstract: The present invention is related to a front-end circuit for an optical communication system including a laser module arranged for transmitting bursts of data signals over an optical network and a driving circuit for providing the bursts of data signals to the laser module. The front-end circuit further includes receiver means in connection with said laser module and arranged for receiving from the optical network optical echo signals. The laser module includes a laser diode arranged for transmitting the bursts of data signals. The driving circuit is arranged for setting a disabling signal for stopping the laser diode from transmitting bursts of the data signals. Fiber-related information can be extracted from the echo signals, such as distance-resolved optical fiber reflections and fiber attenuation.