Abstract: In an optical fiber network for transmitting optical signals in a robot having three or more joints connecting a plurality of links in series such that the links include two end links located at either end and intermediate links provided between the two end links, and the links connected by the joints are moveable relative to each other, a plurality of optical transceiver modules are provided on the links such that at least one optical transceiver module is provided on each link; and a plurality of optical fiber cables connect the optical transceiver modules in a ring; wherein at least one end of each optical fiber cable connecting the optical transceiver modules provided on different links is connected to one of the optical transceiver modules provided on the intermediate links.

Abstract: An OLT (1) is formed by N optical transceivers (11), one PON control circuit (12), and one selection and distribution circuit (13). An optical transceiver selection control signal (SC) is transferred from the PON control circuit (12) to the selection and distribution circuit (13). The optical transceiver selection control signal (SC) indicates the timing of a discovery window, the timing of a grant, and a logical link identification number of a registered ONU assigned to the grant (a logical link identification number for a logical link with the registered ONU). The selection and distribution circuit (13) selects one optical transceiver (11-s (s is an integer falling within a range of 0 to N?1)) from the optical transceivers (11-0 to 11-N?1) based on the optical transceiver selection control signal (SC) from the PON control circuit (12).

Abstract: A method of providing data using visible light communication (VLC) and a VLC system therefor is provided, the method for easy utilization, in a user terminal, of information provided by a lighting apparatus based on a position at which the lighting apparatus is provided.

Abstract: A method distributes clock synchronization information within an optical communications network that includes a plurality of network elements. The method receives an ingress clock synchronization message at a first network element. The ingress clock synchronization message includes a clock synchronization message identifier and a correction field. The clock synchronization message identifier is inserted into an optical channel frame overhead and the ingress clock synchronization message is inserted into an optical channel frame payload. The optical channel frame overhead and the optical channel frame payload are transmitted across the first network element, across the network to a second network element, and across the second network element. A transit time of the clock synchronization message identifier is determined across each of the network elements.

Abstract: A high-speed multi-channel data transmission method is disclosed. The method includes that: a data sender replaces data at intervals of N periods with frame headers in data channels, sequentially stores the data replaced with the frame headers in the data channels in a Deskew channel, and sends the data in the data channels and data in the Deskew channel to a data receiver; the data receiver determines frame header locations of the data channels and the Deskew channel, calculates offsets of the data channels according to the frame header locations, and performs period compensation for the data channels according to the calculated offsets to keep the frame header of each data channel and the frame header of the Deskew channel in a relative relationship the same as that at the data sender; and the frame headers on the data channels and the corresponding data on the Deskew channel are replaced to finish data restoration.

Abstract: A method distributes clock synchronization information within an optical communications network having a plurality of network elements. The method receives an ingress clock synchronization message at a first network element. The ingress clock synchronization message includes a clock synchronization message identifier and a correction field. The clock synchronization message identifier is inserted into an optical channel frame overhead and the ingress clock synchronization message is inserted into an optical channel frame payload. The optical channel frame overhead and the optical channel frame payload are transmitted across the first network element, across the network to a second network element, and across the second network element. A transit time of the clock synchronization message identifier is determined across each of the network elements.

Abstract: The disclosure concerns quantum repeater network system that does not need any matter qubit. According to the quantum repeater network system for performing quantum communication between one transmitter/receiver and the other transmitter/receiver via transmission repeaters and reception repeaters, each of the transmission repeaters prepares quantum systems in an irreducibly entangled state, each of the quantum systems being associated with a reception repeater as a transmission destination, and transmits, to the associated reception repeater, each of the quantum systems in the irreducibly entangled state together with a quantum system entangled with the quantum system.

Abstract: An information communication method of transmitting a signal using a change in luminance is provided. The information communication method includes: determining a pattern of the change in luminance, by modulating the signal to be transmitted; and transmitting the signal, by at least one light emitter changing in luminance according to the determined pattern of the change in luminance. In the determining, a first luminance change pattern corresponding to a body, a second luminance change pattern indicating a header for specifying the body, and a third luminance change pattern indicating another header different from the header are determined. In the transmitting, the header, the body and the other header are transmitted by the at least one light emitter changing in luminance according to the first luminance change pattern, the second luminance change pattern, the first luminance change pattern and the first luminance change pattern in the stated order.

Abstract: A method and apparatus for time synchronization between a plurality of nodes in a network. The apparatus distinguishes between an optical synchronization signal for synchronization between nodes and an optical data signal for data transmission, and synchronizes nodes with each other using the optical synchronization signal.

Abstract: An information communication method of transmitting a signal using a change in luminance is provided. The information communication method includes: determining a pattern of the change in luminance, by modulating the signal to be transmitted; and transmitting the signal, by at least one light emitter changing in luminance according to the determined pattern of the change in luminance. In the determining, a first luminance change pattern corresponding to a body which is a part of the signal and a second luminance change pattern indicating a header for specifying the body are determined. In the transmitting, the header and the body are transmitted by the at least one light emitter changing in luminance according to the first luminance change pattern, the second luminance change pattern, and the first luminance change pattern in the stated order.

Abstract: An apparatus and method for scalable frame alignment in a high data-rate communications system. OTUk/ODUk frame alignment uses serial processing of a match vector, or serial processing of received OTUk/ODUk bytes to reduce the footprint occupied by the processing logic.

Abstract: There is provided a communication control device including a communication control processing portion that performs at least one type of communication control processing when a control signal that requests a response signal is received from a partner device, a transmission processing portion that transmits the response signal to the partner device after the processing that the communication control processing portion performs when the control signal is received from the partner device, a processing time measurement portion that measures time that is consumed by the processing by the communication control processing portion, and a processing content setting portion that, based on the measured processing time that has been measured by the processing time measurement portion and on a response processing time for the response to the control signal, sets content of processing that the communication control processing portion will be made to perform within the response processing time.

Abstract: An apparatus includes a bank of optical detectors, an input optical filter and a selector. The optical detectors are configured to output respective detection indications in response to detecting a presence of an optical signal. The input optical filter is configured to receive an input optical signal having an input wavelength, and to route the input optical signal to one of the optical detectors in the bank depending on the input wavelength. The selector is configured to select an output wavelength based on the detection indications of the optical detectors, and to cause generation and transmission of an output optical signal at the selected output wavelength.

Abstract: A method and apparatus are provided for presenting multimedia content to a caller and/or a called party in association with a telephone call. Content may be presented pre-ring (before the called party's telephone rings), in-call, and/or post-call. Content presented to a party may be related to another party participating in the call or may be related to a third party (e.g., an advertiser that paid for the ability to have its content presented). Presented content may be actuable, to allow a caller to change the destination of a call, take advantage of an offer presented to him or her, redeem a coupon, schedule or queue a subsequent call, etc. To find a desired destination party, a caller may initiate a manual or automatic search of his or her local contacts (on his telephone) and/or a central or global directory or contact list.

Abstract: The present invention discloses a clock recovery circuit, an optical receiver, and a passive optical network device. In the clock recovery circuit provided by the embodiment of the present invention, a first signal indicating whether a data loss abnormality occurs in initial serial data is introduced at a side of a phase detector, and a phase adjustment control signal is output to a phase adjustor according to a state of the first signal; and the phase adjustor performs different types of phase adjustment according to a state of the initial serial data, so that a data sampler can recover an accurate clock when the initial serial data is normal and can implement smooth switching of output clock information in special cases such as initial serial data clock loss or recovery, and no great abrupt phase change occurs, thereby ensuring stable and reliable working of a system.

Abstract: The display device according to the present invention comprises a substrate and at least one optical coupler having an optical receiver and an optical transmitter formed on the substrate, wherein the optical transmitter transmits an optical signal to the optical receiver.

Abstract: Methods, systems, and devices are described for detecting and correcting a cycle slip occurrence in a coherent receiver. Unique words are used in each received frame to detect phase changes that indicate the occurrence of a cycle slip within a frame. The location of the cycle slip is identified based on measurements made within the frame. Those measurements include phase estimation measurements and reliability measurements. A phase of a portion of the frame subsequent to the identified location of the cycle slip is adjusted to correct for the cycle slip. By combining phase estimates of symbols from both vertical and horizontal polarizations, the location of the cycle slip may be more accurately determined because the measurement windows is less susceptible to thermal noise. The phase estimates are combined by adjusting a phase of the symbols of one polarization to match a phase of the symbols of the other polarization.

Abstract: The present invention relates to the Passive Optical Network (PON) technology, and a method for sending an upstream transfer frame in a PON is provided. The method includes: after success of link, sending a preamble according to an allocated time slot, sending a burst synchronization delimiter, and then sending successively a burst header, a Gigabit-Capable Passive Optical Network (GPON) Transmission Convergence (GTC) frame header, and GTC frame data. In the sent synchronization delimiter, the number of zeros on the odd bits is N, the number of non-zeros on the odd bits is M, a relation |N?M|?1 is satisfied, the max number of zeros in a continuous zero group is X, the max number of non-zeros in a continuous nonzero group is Y, and a relation |X?Y|?1 is satisfied. A device for sending an upstream transfer frame in a passive optical network is further provided.

Abstract: In the present invention, wasted power consumption caused when a clock and data recovery unit in an optical network unit in a PON system is activated from a power-saving state is reduced and rapid, secure communication is performed. A clock and data recovery unit includes a phase-locked loop that can be set to normal mode or power-saving mode and that includes a voltage-controlled oscillator and recovers a clock signal and a data signal from input signals. The clock and data recovery unit includes a reference clock multiplier circuit that multiplies a reference clock signal and outputs the multiplied reference clock signal; and a frequency training loop that includes the same voltage-controlled oscillator and performs synchronous oscillation training by the voltage-controlled oscillator using the reference clock multiplier circuit before the phase-locked loop transitions from power-saving mode to normal mode.

Abstract: A method and apparatus for time synchronization between a plurality of nodes in a network. The apparatus distinguishes between an optical synchronization signal for synchronization between nodes and an optical data signal for data transmission, and synchronizes nodes with each other using the optical synchronization signal.

Abstract: A method distributes clock synchronization information within an optical communications network having a plurality of network elements. The method receives an ingress clock synchronization message at a first said network element. The ingress clock synchronization message includes a clock synchronisation message identifier and a correction field. The clock synchronisation message identifier is inserted into an optical channel frame overhead and the ingress clock synchronisation message is inserted into an optical channel frame payload. The optical channel frame overhead and the optical channel frame payload are transmitted across the first network element, across the network to a second said network element, and across the second network element. A transit time of the clock synchronisation message identifier is determined across each of the network elements.

Abstract: A transmitter and a receiver for an optical telecommunication system of the WDM type are disclosed. In one aspect, the transmitter uses a chromato-temporal encoder which, with each block of symbols to be transmitted, associates a code matrix, where each element of the matrix corresponds to a wavelength and a use of the channel. The transmitter includes multiple modulators, where each modulator modulates a laser beam at a wavelength during a use of the channel by an element corresponding to the code matrix. The beams modulated in this manner are multiplexed in an optical fiber. Another embodiment using both a wavelength and a polarization encoding is also proposed.

Abstract: A transmission apparatus includes: a plurality of logical lanes; a receiver configured to receive a signal including synchronization information of a frame; a distributor configured to divide data included in the received signal into frame elements and cause the plurality of logical lanes to store the data; and a transmitter configured to transmit the data stored in the logical lanes to lines corresponding to the logical lanes. When the data is stored in the plurality of logical lanes, the distributor groups the logical lanes into a plurality of groups and associates the frame elements with the synchronization information.

Abstract: An Ethernet adapter system may include a transmitter to insert a payload type identifier sequence in a generic frame procedure header to indicate that a network is a converged enhanced Ethernet network. The transmitter may insert idle sequences in a stream of data frames transmitted along a link. The system may include a receiver to recognize a condition and to force a loss of synchronization condition on the link that will be converted by the receiver into a loss of light condition. The receiver may scan the transmitted stream of data frames for invalid data frames and introduce a code into the stream of data frames whenever an invalid data frame is detected.

Abstract: An OLT that receives a signal in which transmission signals having a plurality of transmission rates are time-division multiplexed, as a received signal, and performs data reproduction by selecting reproduction data to be reproduced, among oversampled signals obtained by oversampling the received signal. The OLT includes a data-signal-information acquisition unit that acquires a transmission rate of a received signal targeted for a process of the data reproduction, a sampling frequency control unit that determines a sampling frequency to be used for the oversampling based on the transmission rate, and a sampling-clock generation unit that generates a clock signal having the sampling frequency determined by the sampling-frequency control unit, and performs the oversampling based on the clock signal.

Abstract: Disclosed are a phase locked loop (PLL) of a digital scheme and a method thereof. More specifically, disclosed are a digital phase locked loop having a time-to-digital converter (TDC), a digital loop filter (DLF), and a digitally controlled oscillator (DCO), and that is designed to have a constant jitter characteristic at all times even though an operating condition of a circuit varies according to a process, voltage, temperature (PVT) change, and a method thereof.

Abstract: An optical transmission system includes at least a first optical link to transmit a first data signal as a part of a multi-lane signal and a second optical link to transmit a second data signal as another part of the multi-lane signal; on the transmission side, a reference clock is constantly applied to the first data signal of the first optical link, and a delay clock is applied to the second data signal responsive to a control signal on the second optical link; on the receiving side, the phase of a first clock signal detected from the first data signal received on the first optical link and the phase of a second clock signal detected from the second data signal received on the second optical link are compared, and the control signal is detected from the comparison result.

Abstract: Provided is an optical line terminator (OLT) to recover packet data and a clock from an optical signal including a silent interval. The OLT may receive packet data and a clock from at least one optical network unit (ONU). Even in a silent interval in which the at least one ONU does not transmit packet data, the OLT may successfully recover the clock.

Abstract: In an optical communication system containing a primary line and backup line card, a method includes providing interfaces for the primary and backup line card, each line card including a transmitter and receiver; and selecting output from the transmitter from either the primary or back up line card including selecting the backup line card when the primary line card encounters a failure.

Abstract: A timing interface module installs within a rack to increase bandwidth. The timing interface module receives a reference timing signal and outputs the reference timing signal to an optical multiplexer. The optical multiplexer also receives multiple data streams of different formats, and the optical multiplexer synchronizes the multiple data streams to the reference timing signal.

Abstract: The present invention includes optical phase modulation circuits (26A, 26B) as one and another transmission processing devices that transmit a plurality of pieces of data in a phase-synchronous manner, and one and another synchronization drive means (33A, 33B) for synchronously control transmission operations of the optical phase modulation circuits.

Abstract: A wavelength dispersion amount estimation method, a wavelength dispersion compensation circuit, and a receiving device which rapidly estimate and set a wavelength dispersion amount to compensate with high accuracy at the receiving device which compensates waveform distortion at an optical fiber transmission path.

Abstract: A method for synchronizing a plurality of clocks arranged within a plurality of nodes of a packet-switching network comprises comparing parameters that relate to the plurality of clocks in order to determine master-slave relationships between the plurality of clocks, and exchanging time-stamped messages over the packet-switching network each time between a master clock and an associated slave clock to make the associated slave clock subservient to the master clock. A node of the packet-switching network comprises a frequency source controlled by a synchronous physical layer technology. The parameters that relate to a clock of the node comprise a parameter that relates to the frequency source to determine the master slave relationships based on one property of the frequency source.

Abstract: The present disclosure provides to Optical Transport Network (OTN_ synchronization systems and methods that maintain proper sequential ordering of events at nodes which may be utilized in performing root cause analysis or diagnosing network performance. In an exemplary embodiment, the systems and methods utilize functionality incorporated into OTN providing a cost effective and standards-based approach to nodal synchronization. Once synchronized, network events are logged with an appropriate timestamp enabling a determination of a sequential order of network events can be determined. Further, the node timestamps may be synchronized, with microsecond or even sub-microsecond of precession which is critical in diagnosing network failures or slow traffic recovery.

Abstract: An optical line terminal includes the transmission rate control table for storing a minimum bandwidth for an emergency status for each of optical network units in addition to a maximum assigned bandwidth in a normal status. When a decrease in a supply power is detected, the optical line terminal calculates a transmission clock rate providing a minimum bandwidth required by each optical network unit with reference to the transmission rate control table. The optical line terminal determines change timing of downstream and upstream transmission clock rates, and change timing of upstream data for time-division multiplexing to instruct each of the optical network units. Both the optical line terminal and the optical network unit change the transmission clock rates with substantial synchronization therebetween.

Abstract: One embodiment provides an Ethernet Passive Optical Network (EPON) system for clock transport. The system includes a reference clock configured to generate a frequency-reference signal, an optical line terminal (OLT) coupled to the reference clock, and an optical network unit (ONU). The OLT includes a clock generator configured to generate an OLT clock based on at least the frequency-reference signal. The ONU includes an optical transceiver, a clock recovery module, and a clock output mechanism. The optical transceiver is configured to transmit optical signals to and receive optical signals from the OLT. The clock-recovery module is configured to recover the frequency-reference signal from the received optical signals. The clock output mechanism is configured to output the recovered frequency-reference signal, thus facilitating transport of the frequency-reference signal over the EPON.

Abstract: Systems and methods are provided for a media device including one or more movement-based interfaces for interfacing with or controlling the media device.

Abstract: An Ethernet adapter system may include a transmitter to insert a payload type identifier sequence in a generic frame procedure header to indicate that a network is a converged enhanced Ethernet network. The transmitter may insert idle sequences in a stream of data frames transmitted along a link. The system may include a receiver to recognize a condition and to force a loss of synchronization condition on the link that will be converted by the receiver into a loss of light condition. The receiver may scan the transmitted stream of data frames for invalid data frames and introduce a code into the stream of data frames whenever an invalid data frame is detected.

Abstract: Techniques for timing synchronization in an optical orthogonal frequency division multiplexing (OOFDM) system includes providing a time-domain training symbol having a symmetric distribution and producing the training symbol by transmitting a real-valued PN sequence on each subcarrier under the OOFDM. The training sequence includes an initial value, followed by an odd length palindromic sequence of values.

Abstract: Embodiments of the concepts, systems, and techniques disclosed herein are directed to an optically powered, direct-sampling, analog-to-digital converter (ADC) that provides fully formatted, serialized data for transmission over optical fiber from a remote location. Such a system and method of use thereof requires less electrical power, fewer components, and less complexity than previous systems and methods and achieves an all-optical-fiber implementation that provides complete electrical and electromagnetic interference (EMI) isolation for the remote ADC. These concepts, systems, and techniques simplify the overall remote sensing architecture by locating the ADC near the sensor and transferring pure digitized signals back to the processor.

Abstract: Aspects of the invention provide transmitters and receivers for managing multiple optical signals. High order modulation, such as phase and/or amplitude modulation, is used to achieve multiple bits per symbol by transporting multiple asynchronous data streams in an optical transport system. One or more supplemental multiplexing techniques such as time division multiplexing, polarization multiplexing and sub-carrier multiplexing may be used in conjunction with the high order modulation processing. This may be done in various combinations to realize a highly spectrally efficient multi-data stream transport mechanism. The system receives a number of asynchronous signals which are unframed and synchronized, and then reframed and tagged prior to the high order modulation. Differential encoding may also be performed. Upon reception of the multiplexed optical signal, the receiver circuitry may employ either direct detection without a local oscillator or coherent detection with a local oscillator.

Abstract: According to one aspect, the invention relates to a device (20) for synchronizing optical pumping entanglement sources (141, 142) in a quantum communication network, including a pulsed light source (21) enabling the emission of telecom-wavelength light pulses (I1,I2), which are distributed in parallel with all of the entanglement sources in order to provide an optical clock common to said entanglement sources and including, for each entanglement source, a device (243, 253) for converting the frequency of the distributed light pulse, thereby enabling a light pulse to be generated at a wavelength adapted to the optical pumping of the entanglement source in order to generate pairs of entangled photons.

Abstract: An apparatus comprising a wavelength division multiplexer (WDM), an optical network unit (ONU) coupled to the WDM, a passive optical network (PON) data over cable service interface specification (DOCSIS) upstream proxy (PDUP) coupled to the ONU and configured to couple to a coaxial cable, and a downstream (DS) optical/electrical (O/E) converter coupled to the WDM and configured to couple to the coaxial cable. An apparatus comprising a WDM, an optical line terminal (OLT) coupled to the WDM, a cable model termination system (CMTS) coupled to the OLT via an upstream external physical (PHY) interface (UEPI), and a DOCSIS and a Quadrature Amplitude Modulation (QAM) unit coupled to the WDM and the CMTS.

Abstract: A transmitting apparatus includes a first circuit to which a base clock and a first clock condition are input, the first circuit outputting a first enable signal based on the base clock and the first clock condition; a second circuit to which the base clock and a second clock condition are input, the second circuit outputting a second enable signal based on the base clock and the second clock condition; a first frame processing circuit receiving a first frame input signal and the first enable signal to output a first frame output signal in synchronization with the first enable signal; and a second frame processing circuit receiving a second frame input signal and the second enable signal to output a second frame output signal in synchronization with the second enable signal.

Abstract: A wireless communications system including a mobile station MS and base stations BS1 and BS2, wherein one or both of the mobile station MS and the base stations BS1 and BS2 is provided with a unit for notifying information of a frame position with the possibility of transmission of packets based on detection of deterioration of a reception quality and wherein the mobile station MS is provided with a unit for determining a frame position without the possibility of transmission of packets and shifting to a peripheral cell detection mode at this frame position based on information of a frame position with the possibility of transmission of packets, whereby it is possible to shift to a peripheral cell detection mode without lowering the transmission efficiency and without complicating the processing.

Abstract: A photon detection system is provided comprising a photon detector, configured to detect photons during intervals when in a receiving state and to output a signal when a photon is received, a controller, configured to generate a time varying gating signal wherein said gating signal switches said detector between the receiving state and a non-receiving state, said controller being configured to receive and process information relating to the times photons are expected to arrive at said detector, the controller being configured to generate the gating signal such that the photon detector is in the receiving state for intervals when photons are expected and also in the receiving state for additional intervals between the intervals when the photons are expected; a detection module, configured to distinguish between when the output signal from the photon detector corresponds to an interval when photons are expected and said additional intervals.

Abstract: A method and system for transmitting data over a Jacobi MIMO channel when using channel state feedback.

Abstract: An optical connection infrastructure has optical conduits between first devices and at least one second device. Dynamic reconfiguration of the optical connection infrastructure can be performed from a first connection topology to a second, different connection topology based on programming of the first devices.

Abstract: Optical Transport Network (OTN) High Order (HO) mapping systems and methods utilize pointer processing to map one HO signal into another similarly sized HO signal. An OTN HO mapping method and circuit include receiving a first HO signal at a first rate, asynchronously mapping the first HO signal into a second HO signal at a second rate, wherein the first rate and the second rate are substantially similar, translating a portion of overhead from the first HO signal to overhead of the second HO signal, utilizing pointers in the overhead of the second HO signal for frame alignment of the first HO signal, and transmitting the second HO signal containing the first HO signal.

Abstract: There is provided an optical signal transmitting apparatus included in an optical communication system which performs communication by transmission and reception of an optical signal indicating digital data. The optical signal transmitting apparatus includes a transmission data generating unit configured to set a data length of each frame constituting the optical signal based on a frequency tolerance of a clock signal on a transmission side and a reception side, and generate digital transmission data having multiple consecutive frames of same contents, each frame having the set data length; and a light emission driving unit configured to drive a light emitting unit to output the optical signal indicating the digital transmission data.