Abstract: Electrical-optical interface devices and methods for use in optical communications systems are disclosed. The electrical-optical interface devices are configured to convert electrical signals to optical signals and optical signals to electrical signals, and are configured to connect to external devices. The electrical-optical interface device is configured to monitor the data transmission between external devices over a primary communication pathway. The electrical-optical interface device is designed to reconfigure itself when it receives information about a communication error so that it automatically utilizes secondary optical communication pathways as redundant optical communication pathways to maintain data communication between the external devices.

Abstract: Anode for burst switching of traffic flows in an optical network switches bursts of traffic flows in different time slots. Time slots are allocated (96) so that a time gap between successive allocated time slots is selected according to a jitter specification of the traffic flow. A map of the allocations controls a burst switch to pass the bursts in their allocated time slots (86). By making the time gap between allocated time slots for successive bursts selectable, the jitter can be controlled more precisely, or the proportion of time slots filled can be increased resulting in better utilization of available bandwidth. The allocation can be made hop by hop. The map can be generated in a distributed and duplicated manner at each node. The allocation can be updated to adapt to changes bandwidth demands.

Abstract: An optical transmitter transmits optical signal including a first signal and a second signal. The second signal is subjected to change in a polarization state relative to a polarization state of the first signal. An optical receiver analyzes a reception characteristic of the second signal and detects, based on the analyzed result, a polarization state of the first signal indicative of a higher signal quality than that of the second signal.

Abstract: A coherent transceiver system includes a local oscillator (LO) light source to generate an LO optical signal. An adaptive fiber array is coupled to the LO light source to dephase the LO optical signal. A balanced detector is coupled to the adaptive fiber array to receive a dephased LO signal from the adaptive fiber array and an optical input signal and to generate a heterodyne signal. A controller receives the heterodyne signal and generates one or more control signals. The adaptive fiber array utilizes the control signals to dephase the LO optical signal.

Abstract: Optical network units (ONUs) for high bandwidth connectivity, and related components and methods are disclosed. A fiber optical network ends at an ONU, which may communicate with a subscriber unit wirelessly at an extremely high frequency avoiding the need to bury cable on the property of the subscriber. In one embodiment, an optical network unit (ONU) is provided. The ONU comprises a fiber interface configured to communicate with a fiber network. The ONU further comprises an optical/electrical converter configured to receive optical downlink signals at a first frequency from the fiber network through the fiber interface and convert the optical downlink signals to electrical downlink signals. The ONU further comprises electrical circuitry configured to frequency convert electrical downlink signals to extremely high frequency (EHF) downlink signals at an EHF, and a wireless transceiver configured to transmit the EHF downlink signals to a proximate subscriber unit through an antenna.

Abstract: An increase in circuit scale is suppressed and a phase variation caused in a transmission path or the like is compensated for.

Abstract: A microwave-frequency source at frequency fM comprises: a dual optical-frequency reference source, an electro-optic sideband generator, an optical bandpass filter, an optical detector, a reference oscillator, an electrical circuit, and a voltage-controlled oscillator (VCO). The sideband generator modulates dual optical reference signals at v2 and v1 to generate sideband signals at v1±n1fM and v2±n2fM. The bandpass filter transmits sideband signals at v1+N1fM and v2?N2fM. The optical detector generates a beat note at (v2?N2fM)?(v1+N1fM). The beat note and a reference oscillator signal are processed by the circuit to generate a loop-filtered error signal to input to the VCO. Output of the VCO at fM drives the sideband generator and forms the microwave-frequency output signal. The resultant frequency division results in reduced phase noise on the microwave-frequency signal.

Abstract: An optical communication link that includes two nodes interconnected by an optical channel that comprises optical fiber(s), and that is used to communicate an optical signal comprising multiple optical signal wavelengths. The first node provides an optical signal onto the optical channel towards the second node, or receives an optical signal from the optical channel from the second node. A Raman pump provides Raman pump power into the optical fiber of the optical channel to thereby perform Raman amplification of the optical signal in the optical fiber. The second node determines a quality measurement of at least of optical wavelength signals transmitted by the first node to the second node. The second node also transmits information from the quality measurement back to the first node. A controller at the first node controls at least one parameter of the Raman pump in response to this transmitted information.

Abstract: Provided are a method and device for configuring an OTDR test parameter set. The above-mentioned method comprises: an FMS acquiring related information about an ODN according to a test result fed back by an OTDR; and the FMS configuring a test parameter set required for one or more subsequent OTDR tests according to the related information. According to the technical solution provided in the disclosure, the test parameter set required for initiating an OTDR test can be accurately acquired.

Abstract: An optical transceiver module includes an optical fiber and an optical fiber positioning structure that fixes the optical fiber. The optical fiber positioning structure includes a first positioning part that fixes the said optical fiber, and a first supporting part that fixes the first positioning part on a case of the optical transceiver module. The first positioning part includes a first end face and a second end face opposite to one another, and a first through-hole that connects the first and second end faces. The inner diameter of the first through-hole is substantially equal to the diameter of the optical fiber, and the optical fiber is fixed within the first through-hole. The first supporting part includes an accommodating portion for accommodating the first positioning part. The first positioning part is fixed in the accommodating portion.

Abstract: Methods and apparatuses are provided to modify existing overlay system architectures in a cost effective manner to meet the growing demand for narrowcast services and to position the existing overlay systems for additional future modifications. The implementations of the improved overlay system of this disclosure re-digitize narrowcast analog signals after they have been QAM modulated and upconverted to RF frequencies and replace the analog narrowcast transmitters with digital narrowcast transmitters. In the fiber nodes, the received narrowcast signals are converted back to analog signals and combined with analog broadcast signals for transmission to the service groups.

Abstract: An ONU receiving an optical signal from an OLT including PON controllers includes: an optical receiver to convert, into an electric signal, an optical signal having a single optical wavelength set out of plural optical wavelengths; and a control frame extractor to extract and hold wavelength correspondence information indicating correspondence between MAC addresses of the PON controllers received from the OLT and the optical wavelengths.

Abstract: A nonlinear compensation unit (300) includes a first compensation unit (350) and a second compensation unit (360). The first compensation unit (350) compensates for each of two polarization signals Ex and Ey so as to cancel a first amount of phase rotation which is the amount of phase rotation calculated based on the signal strength of the two polarization signals Ex and Ey. The second compensation unit (360) compensates for each of the two polarization signals Ex and Ey so as to cancel a second amount of phase rotation which is the amount of phase rotation calculated based on the perturbative component of the two polarization signals Ex and Ey. The first compensation unit (350) includes a strength calculation unit (302), a first filter unit (304), and a first phase modulation unit (306). The second compensation unit (360) includes a perturbative component calculation unit (316), a second filter unit (318), a second phase modulation unit (322), and a third phase modulation unit (330).

Abstract: A current mirror circuit that amplifies a reference current generated by a current source at a first magnification to supply a mirror current to a load circuit. The current mirror circuit includes a first transistor and a second transistor that share a power supply, and a drain potential mirror unit that amplifies the reference current at a second magnification to generate a first current, that amplifies a generated first current at a third magnification to generate a second current, and that supplies a predetermined potential determined based on the second current to a drain of the second transistor. The mirror current is supplied from the second transistor to the load circuit based on a potential of a gate of the first transistor determined based on the reference current.

Abstract: An optical communication device and a control method thereof are provided. The optical communication device includes a driving module, a data transmission module, a light emitting module, and a feedback module. The driving module generates a driving current. The data transmission module generates a data current according to a piece of data. The light emitting module is electrically connected to the driving module and the data transmission module directly and emits visible light according to an illuminating current generated by combining the driving current with the data current. The feedback module adjusts a direct current (DC) potential of one of the driving current and the data current so as to make an average intensity of the visible light equal a preset intensity.

Abstract: A distributed antenna system is provided for communicating with a plurality of base stations. The distributed antenna system includes a system controller and a master unit communicating with at least one of the plurality of base stations. A remote unit communicates over a high data rate media with the master unit and/or a downstream remote unit. Alternatively, the distributed antenna system includes a controller and a digital time/space crosspoint switch controlled by the controller. A digitizing transceiver is in communication with the digital time/space crosspoint switch. The crosspoint switch is configured to transmit and receive digital data through the digitizing transceiver.

Abstract: An optical frame is received over an optical link within an optical network. The optical frame contains a payload of aggregated data, an alignment value, and a bit interleaved parity value. The content of the optical frame is aligned based on the alignment value. The bit interleaved parity value is monitored. In response to the monitoring, a transmission quality of the transmission link is determined.

Abstract: The present invention relates to the field of network communications. An Optical Line Terminal (OLT) allocates a Pseudo Wire (PW) label of an access segment PW for a port, and establishes a corresponding relationship between the port information and the PW label; and carries the corresponding relationship between the port information and the PW label in a label management message, and sends the label management message to an Optical Network Unit (ONU) so that the ONU updates a forwarding table, in which the label management message adopts an access network management protocol. As a consequence, a problem of supporting Pseudo Wire Emulation Edge-to-Edge (PWE3) on a data plane of an access segment of an access network is solved under the conditions that device complexity of the ONU is not increased and a configuration of the ONU is slightly changed.

Abstract: According to an example, nodes request access to a shared resource in a prioritized optical arbitration system. Each node attempts to extract a wavelength corresponding to a priority level selected by the node from a waveguide. A node is granted access to the resource according to priority level, and is to extract from the waveguide the corresponding wavelength.

Abstract: Methods, systems, and devices are described for deriving an identifier encoded in a visible light communication (VLC) signal. One method includes capturing a first part of the VLC signal; extracting, from the first part of the VLC signal, a first pattern of bits representing at least a portion of the identifier encoded in the VLC signal; comparing the first pattern of bits to different portions of a plurality of identifiers; and identifying, based at least in part on the comparing, a subset of the plurality of identifiers as candidate matches to the identifier encoded in the VLC signal.