Abstract: An optical transceiving apparatus includes an optical transmitting device performing polarization multiplexing on and transmitting as polarization multiplexed signal light, a first signal light of a predetermined polarization direction and a second signal light of a polarization direction different from the predetermined polarization direction; an optical receiving device receiving the signal light transmitted from the optical transmitting device through an optical transmission path; an acquiring unit acquiring information indicative of magnitude relation of intensity between the first signal light and the second signal light included in the signal light received by the optical receiving device; and a control unit controlling the magnitude relation of intensity between the first signal light and the second signal light included in the signal light output from the optical transmitting device, to be opposite to the magnitude relation indicated by the information acquired by the acquiring unit.

Abstract: Virtual optical network (VON) provisioning using implicit encoding of mapping constraints may include evaluating mapping choices to exclude certain mapping patterns before evaluating the mapping patterns. For each virtual node in a VON request, candidate physical nodes may be assigned and evaluated for compliance with constraints associated with the VON request. The constraints may be expanded to allow for various selection criteria for the VON request. Multiple VON requests may be simultaneously evaluated to find optimal solutions for the physical network.

Abstract: An optical receiver includes: a frontend circuit configured to generate a baseband signal representing a received optical signal by using local oscillator light; a frequency offset estimator configured to estimate a frequency offset of the baseband signal; a frequency offset corrector configured to correct the frequency offset of the baseband signal according to an estimation result by the frequency offset estimator; a phase recovery configured to recover a modulated phase from the baseband signal for which the frequency offset is corrected; a data recovery configured to recover transmission data according to the modulated phase recovered by the phase recovery; and a controller configured to control an operation of the frequency offset estimator according to a phase error of the baseband signal for which the frequency offset is corrected.

Abstract: The integrated optical receiver module includes a plurality of PDs each converting an optical signal to a current signal, and outputs a current signal selected from a plurality of current signals. The RSSI circuit converts the current signal into a voltage signal, outputs a first amplified signal obtained by amplifying the voltage signal by a first gain, and outputs a second amplified signal obtained by amplifying the voltage signal by a second gain larger than the first gain.

Abstract: An optical transceiver device is provided, including an O/E transceiver module, an optical switching module and a switching control module, for providing network communication services for a first and a second optical fiber network equipment. The O/E transceiver module is an integrated chip having multiple transceiver units integrated therein. The switching control module is connected to an in-line equipment and the optical switching module for controlling the optical switching module to execute corresponding optical path switching operation according to an optical path switching control signal output from the inline equipment. In comparison with conventional optical transceiver devices, the invention is advantageous of simple structure, smaller volume and more flexible optical path switching.

Abstract: The present invention relates to a method, an apparatus, and a system for processing a flexible-rate signal. A signal from a client side is encapsulated to n optical channel data unit ODU signals. The n ODU signals are encapsulated to a flexible optical channel transport unit OTU signal. A nominal bit rate of the flexible OTU signal varies according to a value of n and the n is an integer greater than or equal to 1.

Abstract: A network apparatus used in an optical network is disclosed. The network apparatus includes one or more first tunable and temperature controlled (TTC) lasers, one or more transmitters each of which is connected to one of said one or more TTC lasers, one or more second TTC lasers, one or more digital signal processing (DSP) transponders (TPNDs) each of which is connected to one of said one or more second TTC lasers, one or more receivers, and a controller to control said one or more transmitters and said one or more DSP TPNDs, wherein said one or more transmitters defragment an optical access spectrum, and said one or more DSP TPNDs exploit a newly available spectrum. Other apparatuses, systems, and methods also are disclosed.

Abstract: Systems and methods in accordance with embodiments of the invention convert satellite signals to an intermediate frequency signal and selecting modulated digital data within the satellite signals for content decoding. One embodiment includes an optical low noise block converter (LNB) including a digital channelizer switch configured to select at least one content channel from an input signal including a plurality of content channels modulated onto a carrier and to output an optical signal including the selected at least one content channel.

Abstract: In one embodiment, a replacement network communications path is determined using dedicated resources of an existing path. One or more network elements in a network determines a new communications path between a first network node and a second network node in the network while an existing communications path is currently configured in the network to carry traffic between the first and second network nodes. The existing communications path includes one or more exclusive physical resources dedicated to the existing communications path. The new communications path includes at least one of said exclusive physical resources dedicated to the existing communications path. One embodiment includes: subsequent to said determining the new communications path, removing the existing communications path from service, and then instantiating the new communications path, with the new communications path including said at least one of said exclusive physical resources.

Abstract: A hybrid communications system implements different communication technologies to communicate data and information for particular communications directions in different portions of the system. Power line communications (PLC) signaling is used to deliver data and information from a gateway device to a light access point. Visible light communications (VLC) signaling is used to communicate data and information from the light access point to a user equipment (UE) device. Wireless radio signaling, wireless infrared (IR) signaling, or a combination of wireless IR signaling and PLC signaling is used to communicate data/information from the UE device to the gateway device. To efficiently control the VLC communications channel between the light access point and UE device, the UE device measures the VLC channel, e.g., calculating SNRs on a per VLC tone basis, and communicating VLC channel quality feedback information to the gateway device, which is forwarded to the light access point.

Abstract: An optical transmission device in an optical transmission network including nodes, provided to one of the nodes, the optical transmission device including: a receiver to receive optical signals which have different wavelengths and are multiplexed, an optical detector to detect a strength of the optical signals, a switch to set switching control information including switching request information, each corresponding to one optical signal of the optical signals, and a transmitter to transmit the switching control information by an optical signal, wherein the switch sets, in information indicating a signal fail, the switching request information corresponding to the one optical signal in the switching control information based on the strength of one optical signal of the optical signals.

Abstract: A system, method and apparatus for power saving using burst-mode transmission over point-to-point physical connections. In one embodiment, a physical layer device (PHY) is provided that includes a data detector that is configured to generate a first control signal upon receipt of a non-idle code group over an interface between the PHY and a media access control (MAC) device and to generate a second control signal when all data received from the MAC device has been transmitted by the physical layer device. The PHY also includes a laser for transmission of data over an optical network cable, the laser being configured to perform a first transition from an off state to an on state based on the first control signal, and to perform a second transition from the on state back to the off state based on the second control signal.

Abstract: A communication system comprises a passive optical network (PON) having an optical line terminal (OLT) coupled to a plurality of optical network terminals (ONTs) through a power splitter. Each ONT is coupled to the power splitter via a subscriber line. A switch is coupled to each subscriber line, and all of the switches are coupled to a control element. A power element is configured to receive optical signals communicated by the PON and to convert the optical signals into electrical power for use by the control element. The OLT is configured to detect a rogue ONT and to communicate with the control element for opening the switch that is coupled to the subscriber line of the rogue ONT, thereby optically isolating the rogue ONT from the rest of the PON.

Abstract: A communication device includes a signal correcting unit that performs signal correction on an electric signal indicating information to be transmitted to reduce signal deterioration occurring in transmission of the electric signal; a conversion unit that converts the electric signal subjected to the signal correction into a digital signal on which information indicating the signal correction performed by the signal correcting unit is superimposed; and a light-emitting element that emits light in accordance with the digital signal converted by the conversion unit.

Abstract: A burst-mode Rx is provided that has a wide dynamic range, low pulse-width distortion and low technological overhead. The Rx is capable of processing signals having levels that range from low noise levels up to high noise levels. In addition, the Rx is capable of quickly and simultaneously adapting the TIA gain and the bit decision threshold level, thereby eliminating the need to transmit and receive a training bit sequence prior to transmitting and receiving actual data. By simultaneously adapting the TIA gain and the bit decision threshold level on the first bit of actual data received in the Rx, the Rx is capable of being used with short packets and with packets of varying lengths transmitted from different types of transmitters located in the same network.

Abstract: A transmission circuit of a transmission device transmits a signal to a reception circuit of a reception device via a plurality of signal paths included in a communication line. A first interface circuit is connected to the transmission circuit and one or more signal paths. A second interface circuit is connected to the transmission circuit and remaining signal paths expect for the one or more signal paths. A third interface circuit is connected to the reception circuit and the one or more signal paths. A fourth interface circuit is connected to the reception circuit and the remaining signal paths. An operation for transmitting and receiving the signal via the plurality of signal paths is changed to an operation for transmitting and receiving the signal via the remaining signal paths when the one or more signal paths enter a disconnected state.

Abstract: A method, an apparatus, and a computer program product for communication are provided. The apparatus obtains a message for communication using visible light communication (VLC) through a light emitting diode (LED) luminary device and formats the message using a synchronization signal followed by one or more data signals. The synchronization signal and/or the one or more data signals are modulated using a Frequency Shift Keying (FSK) modulation scheme. The apparatus further receives a dimming level value associated with a brightness of light to be emitted from the LED luminary device, generates a waveform with frequencies based on the formatted message and a duty cycle for the LED luminary device based on the dimming level value, and sends the generated waveform to the LED luminary device for communication using VLC.

Abstract: An apparatus comprising an optical receiver configured to receive a plurality of orthogonal frequency-division-multiplexed (OFDM) symbols comprising a first OFDM symbol and a second OFDM symbol, and a processor coupled to the optical receiver and configured to generate a first decoded signal based on the first OFDM symbol, estimate a plurality of channel parameters adaptively based on the first decoded signal, generate a second decoded signal based on the second OFDM symbol, wherein the second decoded signal is generated using the plurality of channel parameters, and wherein phase recovery is performed on the first OFDM symbol using a number of pilot subcarriers prior to generating the first decoded signal.

Abstract: A data rate control system for an optical line terminal (OLT) may include a processor, an OLT Medium Access Control (MAC) device that includes passive optical network (PON) ports that are mapped to identifiers, and a switch device coupled to the OLT MAC device. The OLT MAC device may determine that a PON port is congested, and may transmit a message to the switch device indicates the congestion at the PON port based on the mapped identifier. The switch device may transmit data items to the OLT MAC device for transmission over the PON ports at data rates respective to the PON ports, may receive the message, and may reduce the rate at which the data items are being transmitted to the OLT MAC device for transmission over the congested PON port without changing the rates at which other data items are being transmitted to the OLT MAC device.

Abstract: A method comprising applying an In-phase (I) offset to an I component of an orthogonal pseudo-random coded direct current (DC) bias signal, applying a Quadrature-phase (Q) offset to a Q component of the orthogonal pseudo-random coded DC bias signal, applying an I dither signal to an I Mach-Zehnder modulator (MZM), wherein the I dither signal is based on the I component of the orthogonal pseudo-random coded DC bias signal, applying a Q dither signal to a Q MZM, wherein the Q dither signal is based on the Q component of the orthogonal pseudo-random coded DC bias signal, and performing arbitrary waveform generation (AWG) by modulating an analog data signal onto an optical carrier signal via the MZMs, wherein the I offset and the Q offset are selected to mitigate crosstalk between the I MZM and the Q MZM due to a finite extinction ratio.