FUJITSU TELECOM NETWORKS LIMITED Patent applications |
Patent application number | Title | Published |
20160109900 | TRANSMISSION DEVICE AND TIME SYNCHRONIZATION METHOD - A transmission device includes a control card and a plurality of IF cards. The control card receives first set time from a host PC and calculates second set time by adding add time corresponding to one cycle of a clock signal that is commonly used by the control card and the IF cards to the first set time. The control card distributes the second set time to each of the IF cards. After each of the IF cards receives the second set time and sets the second set time in an internal timer, when a clock signal is detected, each of the IF cards starts a time measuring operation of the internal timer from the second set time. | 04-21-2016 |
20160020866 | OPTICAL TRANSMITTER AND OPTICAL TRANSMISSION METHOD - An optical transmitter includes a dummy optical source, a polarized wave beam coupler, and an auto gain control (AGC)-system amplifier. The dummy optical source outputs, out of an optical signal in which an optical path signal and an optical packet signal are mixed, a dummy signal having a wavelength identical to that of the optical packet signal. The polarized wave beam coupler multiplexes the dummy signal with the optical signal so that the dummy signal is orthogonal to the optical signal so as to output an output signal. The AGC-system amplifier inputs the output signal, and amplifies the output signal with a predetermined amplification factor corresponding to a power difference between input power and output power of an optical amplifier. | 01-21-2016 |
20150271085 | TRANSMISSION DEVICE AND PAUSE FRAME CONVERSION METHOD - A client interface unit receives a pause frame transmitted from a client device compatible with a relatively low communication rate. A data rate conversion unit generates a plurality of pause frames in accordance with a pause time designated by the received one pause frame and transmits the plurality of pause frames to a frame processing unit compatible with a relatively high communication rate. The frame processing unit stops transmitting a frame destined to the client device in accordance with the plurality of pause frames. | 09-24-2015 |
20150181721 | COMPONENT MOUNTING METHOD AND MOUNTING COMPONENT - A component mounting method includes: placing a mounting component in contact with, and on top of, an electronic component on a substrate, pressing a spring member against the mounting component using a jig such that the mounting component is pushed against the electronic component by the spring member, and fixing the spring member to the substrate, and removing the jig in a direction heading away from a mounting face of the substrate after the spring member has been fixed to the substrate. | 06-25-2015 |
20150103673 | FRAME TRANSMISSION APPARATUS AND METHOD FOR CHECKING NORMALITY - A frame transmission apparatus includes multiple ports provided in a line unit, and a setting control unit. The setting control unit checks the normality of the frame transfer state within the apparatus by transferring a maintenance management frame from a first port to a second port within the apparatus. When the first port is a logical port configured by link aggregation of multiple physical ports, the setting control unit selects each of the multiple physical ports as a transmission source port and transfers multiple maintenance management frames from the multiple physical ports to the second port. | 04-16-2015 |
20150055374 | SWITCHING POWER SUPPLY APPARATUS CORRESPONDING TO ZERO VOLTAGE SWITCHING SYSTEM - In a full bridge type DC-DC converter, a first protective diode is connected between a first node between a first resonance inductor on a primary side and one terminal of a primary winding of a transformer, and a power line on a high voltage side of a power supply. A second protective diode is connected between the first node and a power line on a low voltage side of the power supply. A third protective diode is connected between a second node between a second resonance inductor and the other terminal of the primary winding, and the power line on the high voltage side of the power supply. A fourth protective diode is connected between the second node and the power line on the low voltage side of the power supply. | 02-26-2015 |
20140363154 | OPTICAL SIGNAL PROCESSING DEVICE, OPTICAL SIGNAL PROCESSING METHOD AND RECORDING MEDIUM - An optimization unit in an optical receiver divides a symbol region out of a plurality of symbol regions into which signal points that specifies symbol information included in an optical signal are classified, into a plurality of division regions from the symbol center coordinate of the symbol region. Moreover, the optimization unit accumulates the signal points of the symbol information for every division region in the symbol region. Furthermore, based on the accumulated number of signal points for every division region, the optimization unit controls the average length of a phase estimation unit when the phase noise of the optical signal is calculated. | 12-11-2014 |
20140355980 | OPTICAL COMMUNICATION APPARATUS AND CONTROL METHOD THEREOF - An optical communication apparatus includes a variable resistor unit, a measurement unit, and a control unit. The variable resistor unit is arranged at a pre-stage of an electrical/optical conversion unit, which converts an electrical signal obtained by converting an input packet to an optical signal having a waveform corresponding to a potential difference between a positive phase component and a negative phase component of the electrical signal by using the potential difference. The variable resistor unit provides a resistor that varies a midpoint of potential of the positive phase component or the negative phase component. The measurement unit measures a ratio of a presence period, which is a period where the input packet is present, to a sum of the presence period and a non-presence period. The control unit controls a value of the resistor provided to the positive phase component or the negative phase component based on the ratio. | 12-04-2014 |
20140355978 | OPTICAL TRANSMISSION SYSTEM, OPTICAL TRANSMISSION APPARATUS, AND OPTICAL TRANSMISSION METHOD - An optical transmission system includes a transmission side optical transmission apparatus having a transmitting unit configured to transmit optical signals of a predetermined number of differing wavelengths, and a processor configured to apply to the optical signals transmitted from the transmitting unit, a predetermined offset related to a tilt; and a reception side optical transmission apparatus having a receiving unit configured to receive the optical signals transmitted from the transmitting unit, a measuring unit configured to measure an optical signal count of the optical signals receivable by the receiving unit, and a notifying unit configured to give notification of the optical signal count measured by the measuring unit. The processor adjusts the offset in an increasing direction when the optical signal count notified by the notifying unit increases, and adjusts the offset in a decreasing direction when the optical signal count notified by the notifying unit decreases. | 12-04-2014 |
20140355976 | OPTICAL TRANSMISSION DEVICE, OPTICAL TRANSMISSION SYSTEM, AND OPTICAL TRANSMISSION METHOD - The optical transmission device includes an N×N optical switch, an optical packet receiver and an optical packet generation unit. The N×N optical switch transmits data in which a plurality of optical signals each having a different wavelength is multiplexed. The optical packet receiver detects change in the number of wavelengths of optical signals constituting the data. The optical packet generation unit generates, when the change is detected by the optical packet receiver, data to be transmitted by the N×N optical switch, using optical signals for the number of wavelengths after the change. | 12-04-2014 |
20140340739 | OPTICAL AMPLIFICATION DEVICE AND METHOD OF CONTROLLING OPTICAL MODULE - An optical amplification device includes: an optical module that outputs an amplified light; and a controller that makes the optical module emit a light when an emission command is input into the controller, wherein the controller cancels an inputting of the emission command until a predetermined time passes, when a protection for forbidding a light emission of the optical module is canceled. | 11-20-2014 |
20140205292 | OPTICAL PACKET SWITCHING SYSTEM - An optical packet switching system includes optical packet switching apparatus and an optical packet transmitting apparatus. The optical packet switching apparatus includes client optical delay units for delaying optical packet signals, network optical delay units for delaying one of the network optical packet signals, the network optical delay unit having a longer delay time than the client optical delay unit, an optical switch unit for switching the route of the inputted client optical packet signal so as to be sent out, an optical switch control unit for controlling the optical switch unit. The optical switch control unit is configured in such a manner as to detect a free time slot. The optical packet transmitting apparatus adjusts transmit timing, with which the client optical packet signal is sent out, in such a manner that the client optical packet signal is inserted into the free time slot. | 07-24-2014 |
20140146385 | RAMAN AMPLIFIER - Raman amplifier includes: a pump-light generator configured to supply pump light to a transmission fiber; a measurement circuit configured to measure a relationship between power of the pump light and power of noise output from the transmission fiber with respect to a range from first pump-light power to second pump-light power; a signal detector configured to monitor a supervisory signal in output light of the transmission optical; and a decision unit configured to decide a state of the transmission fiber according to the monitoring result. When the supervisory signal is detected without the pump light, the measurement circuit measures the relationship while increasing the power of the pump light from the first pump-light power. When the supervisory signal is not detected without the pump light, the measurement circuit measures the relationship while decreasing the power of the pump light from the second pump-light power. | 05-29-2014 |
20140112661 | OPTICAL TRANSMISSION DEVICE AND METHOD - An optical transmission device that receives a wavelength division multiplexed optical signal obtained by dividing an optical packet signal and performing wavelength multiplexing and that transmits via an optical switch the received wavelength division multiplexed optical signal includes an optical power level measurement unit configured to measure respective optical power levels of respective optical signals of wavelengths included in the wavelength division multiplexed optical signal, and a routing information determinator configured to determine routing information of the wavelength division multiplexed optical signal on the basis of the measured optical power levels. | 04-24-2014 |
20140092640 | POWER SUPPLY DEVICE - A PFC (Power Factor Correction) circuit improves the power factor of rectified power. Upon receiving output of the PFC circuit, a first DC-DC converter generates a voltage to be supplied to a load. Upon receiving output of the PFC circuit, a second DC-DC converter and a third DC-DC converter generate a control voltage. The second DC-DC converter and the third DC-DC converter are cascade-connected. An input terminal of the third DC-DC converter is connected to both an output terminal of the second DC-DC converter and an output terminal of the first DC-DC converter. | 04-03-2014 |
20130216219 | OPTICAL RECEIVING DEVICE - An optical receiving device includes: an optical amplifier configured to amplify a wavelength multiplexed optical signal; a demultiplexer configured to demultiplex the amplified wavelength multiplexed signal into optical signals of a plurality of wavelengths; optical receivers configured to regenerate the demultiplexed optical signals; error correction units configured to correct a bit error in the regenerated optical signals; and main control unit. The control unit adjusts RXDTV of the optical receiver for receiving optical signals of a given wavelength to the optimal value in the state where the gain of the optical amplifier is lowered from that of a normal operation such that the occurrence of bit errors in the optical signals of the other wavelengths does not exceed the correction capability of the error correction unit. | 08-22-2013 |
20130188654 | FRAME TRANSMISSION SYSTEM - A frame transmission system includes a frame transmitter and a frame receiver. The frame transmitter includes a frame fragmentation unit and a reproduction header appending unit. The frame fragmentation unit fragments an input frame and outputs transfer frames when the length of the input frame exceeds a predetermined fragmentation reference frame length, and does not fragment the input frame and outputs the input frame as a transfer frame when the length of the input frame is less than or equal to the fragmentation reference frame length. The reproduction header appending unit appends a reproduction header to the transfer frames outputted from the frame fragmentation unit. Here, the reproduction header being required when the transfer frames are reproduced at a receiving side. The reproduction header appending unit varies the header length of the reproduction header to be appended to the transfer frame, according to the length of the input frame. | 07-25-2013 |
20130182591 | COMMUNICATION SYSTEM, MONITORING DEVICE OF RING NETWORK, AND FLOW RATE MONITORING METHOD OF RING NETWORK - A communication system includes a plurality of communication devices forming a ring network and a monitoring device. Each of the plurality of communication devices appends, to a frame that the communication device relays, an ID tag indicating the number of communication devices relaying that frame in the ring network. The monitoring device refers to frames received by a predetermined communication device and having the ID appended thereto, and tallies an amount of data for frames for each number of relaying communication devices. | 07-18-2013 |
20130162987 | EXCITATION LIGHT SOURCE FOR RAMAN AMPLIFICATION, RAMAN AMPLIFIER, AND OPTICAL TRANSMISSION SYSTEM - An excitation light source, for Raman amplification, includes a polarization beam splitter (PBS) for splitting a laser beam from an excitation laser into two polarization components, and a polarization beam combiner (PBC) for combining the two polarization components, and a time difference generator provided between PBS and PBC. The time difference generator generates a difference in propagation time between the two polarization components. | 06-27-2013 |
20130148968 | STATION-SIDE APPARATUS AND PON SYSTEM - An OLT, which is a station-side apparatus in a PON system, is connected to an ONU via an optical fiber. The OLT includes: an optical receiver which receives a burst signal from an ONU; a burst header detection unit which detects a certain delimiter pattern included in a received burst signal so as to establish synchronization of the burst signal; and a control unit which allows the burst header detection unit to perform detection of a delimiter pattern during a predicted reception period of a burst signal. | 06-13-2013 |
20130064113 | TRANSMISSION APPARATUS AND TRANSMISSION METHOD - A transmission apparatus includes a digital circuit that has an input circuit into which packets are input at indefinite intervals; a measuring circuit that measures an interval during which no packet is input into the input circuit; a determiner circuit that determines, based on the interval measured by the measuring circuit, whether to insert a given frame between packets input into the input circuit; and a transmitter that inserts, based on a result of determination by the determiner circuit, the given frame between the packets input into the input circuit and sequentially transmits the packets with the given frame therebetween. | 03-14-2013 |
20120315039 | OPTICAL COMMUNICATION DEVICE AND SIGNAL ADJUSTING METHOD - An optical packet switching device causes branching of an optical packet that is input to an optical switch and detects a synchronization pattern having a predetermined number of bits from the branched optical packet. Then, the optical packet switching device calculates a synchronization point indicating a location of the synchronization pattern with respect to a detection timing and controls, in accordance with the calculated synchronization point, a delay amount of a delay element that delays an optical packet ON signal that is output to the optical switch. | 12-13-2012 |
20120300637 | TRANSMISSION APPARATUS AND TRANSMISSION METHOD | 11-29-2012 |
20120294171 | COMMUNICATION DEVICE - A plurality of frame buffers of a communication device store input frames for respective flows, which are units of managing communication. A sequential scheduler and an adjustment scheduler cyclically visit the plurality of frame buffers to read a frame for external output from each frame buffer. The sequential scheduler reads one frame per a visit to each frame buffer at a speed lower than a communication speed of the communication device. The adjustment scheduler reads one or more frames per a visit to each frame buffer such that a restriction on read quantity defined by a reference value greater than the shortest frame size is imposed. | 11-22-2012 |
20120286013 | OPTICAL FIBER CUTTING DEVICE - An optical fiber cutting device includes a fiber holding part holding an optical fiber to be cutting processed, a fiber holding part provided in line with an interval from the fiber holding part and holding a glass core wire part of the optical fiber of which cover is removed, a round blade unit attaching a starting point scratch at a lower surface of a glass core wire of the optical fiber held between the fiber holding parts, and a cutting block pressing an upper surface of the glass core wire corresponding to the starting point scratch from upward, and applying a tensile and a bending stresses to the glass core wire, wherein at least an end face of the cutting block pressing the glass core wire is formed with a rigid material in an R-state along an axis direction of the glass core wire, and the end face is smoothly processed. | 11-15-2012 |
20120141085 | FIBER CLAMP MECHANISM - A fiber clamp mechanism of an optical fiber fusion splicer includes a fiber receiving base and a clamp tip attached to a tip of a stay, in which the fiber receiving base is formed to have a substantially L-shaped cross section in which a thin-walled projecting piece is provided to project upward, and a V-groove with a thin wall holding an optical fiber is formed on an upper surface of the projecting piece, the clamp tip is formed to have a substantially L-shaped cross section in which a projecting piece having a V-shaped pressing portion with a thin wall formed along the V-groove projects downward and is fixed to the tip of the stay, and a tip of the V-shaped pressing portion is formed to have an R-shape along an axial direction of the optical fiber. | 06-07-2012 |
20120106369 | COMMUNICATION SYSTEM, COMMUNICATION APPARATUS, AND RING NETWORK MONITORING METHOD - A communication apparatus forming a ring network sends a test frame that is not designed to be discarded at a block point in the ring network established to discard the user frame and that is configured to have a data size randomly selected from the data sizes permitted for the user frame, from a first communication port connected to a transfer channel in a first direction in the ring network. The communication apparatus determines that the transfer status of the user frame in the ring network is normal when the sent test frame is received via a second communication port connected to a transfer channel in a second direction in the ring network in a predetermined manner. | 05-03-2012 |
20120033929 | GUIDE STRUCTURE OF OPTICAL FIBER AND WIRING METHOD OF OPTICAL FIBER - A guide structure of an optical fiber includes a case in which a plurality of guide pin mounting holes are provided in accordance with the wiring route of the optical fiber, a plurality of guide pins formed of a conductive material, detachably attached to each of the guide pin mounting holes, and pulled out of each of the guide pin mounting holes after wiring the optical fiber, and providing a guide for wiring the optical fiber at the case by inserting each of the guide pins into each of the guide pin mounting holes. | 02-09-2012 |
20120016972 | SNMP AGENT DEVICE AND CONFIGURATION UNDO METHOD - An SNMP agent device includes: a receiving unit configured to receive an SNMP configuration command from a manager device; a configuration processing unit configured to update, when the configuration command designates management information and a configuration value, the management information in the agent device by the configuration value; and a configuration history storage unit configured to store the configuration command, mapping the configuration to a pre-update value of the management information. When the configuration command designates undo, the configuration processing unit performs an undo process of returning the management information updated by a past configuration command to the value occurring before the update. | 01-19-2012 |
20120008491 | RELAY APPARATUS FOR COMMUNICATION FRAMES AND RELAY METHOD - A layer 2 switch (L2SW) includes (i) a leaned information management unit for recording learned information that associates a receiving port, an address of another L2SW, and a source address specified in the original communication frame, when an encapsulated frame, in which a communication frame has been encapsulated by data containing the address of the another L2SW, is received from the backbone network and (ii) a status monitoring unit. The learned information management unit determines the update extent of the learned information, in accordance with a check result of the connection status and thus the occurrence of flooding transfer to a backbone networks side is suppressed. | 01-12-2012 |
20110217041 | PON SYSTEM, STATION-SIDE APPARATUS FOR PON SYSTEM, AND CONTROL METHOD THEREOF - An OLT, which is one of the embodiments of the present invention, is provided with: an allocation request receiving unit that receives a bandwidth allocation request from each of 1 G-ONUs and each of 10 G-ONUs; an allocation execution unit that allocates to each of the ONUs a time slot for data transmission in accordance with an allocation rule based on fairness in time allocation or an allocation rule based on fairness in throughput allocation; and an allocation result notification unit that notifies each of the ONUs of information regarding the time slot. | 09-08-2011 |
20110149988 | COMMUNICATION CONTROLLER - A switch includes: a packet buffer including a plurality of segments for temporarily storing a packet to be relayed, using a segment of a fixed size as a unit of management of a storage area; an input processor configured to receive a packet to be relayed from an external source, refer to an offset, indicating a location in a segment where a free area starts, store a first packet, starting at the location in the segment indicated by the offset, update the location of start indicated by the offset in accordance with the packet size, and store a second packet, starting at the location of start in the segment thus updated; and an output processor configured to read the first and second packets and send the packets to a communication node. | 06-23-2011 |
20110113154 | COMMUNICATION APPARATUS, INTERFACE CARD, AND FAILURE HANDLING METHOD - A communication apparatus of the embodiment is provided with a first IF card that performs a relay process of a data frame in a first direction of a ring network, a second IF card that performs a relay process of a data frame in a second direction of the ring network, a communication-status determination unit that monitors the communication status from the first IF card to the second IF card, a block control unit that sets a new block point to either the first IF card or the second IF card when the communication status is abnormal, and a ring protocol processor that notifies other communication apparatuses that constitute the ring network of information for notifying the switching of a block point in the ring network, which indicates that the new block point has been set. | 05-12-2011 |
20110103804 | OPTICAL TRANSMISSION SYSTEM - An optical transmission system is provided with an optical transmission apparatus, an optical reception apparatus, an optical transmission line redundantly configured with an active system optical transmission line and an standby system optical transmission line, an optical switch that switches an optical transmission line between the active system optical transmission line and the standby system optical transmission line, a variable dispersion compensator placed between the optical switch and the optical reception apparatus, a dispersion amount measuring unit that measures the dispersion amount of the standby system optical transmission line when the active system optical transmission line is being selected by the optical switch, a dispersion compensation amount setting unit that sets the amount of dispersion compensation to be applied to the standby system optical transmission line based on the measured dispersion amount of the standby system optical transmission line, and a control unit that controls, when the optical transmission line is switched from the active system optical transmission line to the standby system optical transmission line by the optical switch, the variable dispersion compensator so that the amount of dispersion compensation becomes the set amount of dispersion compensation. | 05-05-2011 |
20110064088 | COMMUNICATION APPARATUS AND COMMUNICATION CONTROLLING METHOD IN RING NETWORK - A ring connection apparatus according to one embodiment is provided with: a frame receiver that receives frames to be transmitted to one of the plurality of ring networks from each of the plurality of networks; and a frame transmitter that transmits each of frames, a passing frame to be transmitted from a device to another device inside said one ring network and a crossing frame to be transmitted to a device in said one ring network from a device in another ring network different from said one ring network, to said one ring network within the range of a band, which is separately determined in advance. | 03-17-2011 |
20110026941 | VARIABLE DISPERSION COMPENSATION DEVICE - A dispersion compensation device includes a variable dispersion compensator configured to subject an input optical signal to dispersion compensation, an optical receiver configured to convert an optical signal subjected to dispersion compensation into an electrical signal, recover a clock signal and a received data signal from the electrical signal, and output clock lock information indicating whether the clock signal is locked to the electrical signal, a signal processor configured to output bit error rate information on the received data signal, and a controller configured to variably control a dispersion compensation value of the variable dispersion compensator based on the bit error rate information and the clock lock information. | 02-03-2011 |
20110020000 | COMMUNICATION APPARATUS AT SUBSCRIBER HOME - An MC-ONU is an ONU installed at a subscriber's home. The MC-ONU includes: a receiving unit which receives signals transmitted from an OLT at a telecommunications carrier site which has not established a link; a determining unit which determines the OLT, which has not established a link, to be a remote-end device in point-to-point communication on the condition that the signal received for a predetermined period of time is idle signal only; and a transmitting unit which starts transmitting signals to the OLT from the subscriber's home on the condition that it has been determined by the determining unit that the OLT is the remote-end device in point-to-point communication. | 01-27-2011 |
20110008049 | TRANSMISSION APPARATUS, TRANSMISSION CONTROLLING METHOD, AND OPTICAL SUPERVISORY CHANNEL (OSC) PROCESSING APPARATUS - An integrated transmission apparatus includes a plurality of optical supervisory channel (OSC) processing units for processing OSC signals contained in a wavelength division multiplexing (WDM) signal received from a WDM network and a switching unit for performing the path control of synchronous digital hierarchy (SDH) frames. An OSC processing unit transmits the SDH frame, containing wavelength information indicated by, to the switching unit. Another OSC processing unit acquires the SDH frame, containing wavelength information, from the switching unit and sets an OSC signal which is to be appended to the WDM signal to be transmitted, based on the wavelength information. | 01-13-2011 |
20100322633 | TRANSMISSION SYSTEM AND METHOD OF CORRECTING TILT OF THE TRANSMISSION SYSTEM - A transmission system is provided with a transmission apparatus that outputs an ASE light from a transmission light amplifier and with a reception apparatus provided with: a tilt detection unit that detects the optical strength levels of at least two probe lights having different wavelengths from a received ASE light; and a reception light amplifier that performs a first-order tilt correction on light to be output in a linear manner so as to reduce the difference in the optical strength level of the two probe lights detected by the tilt detection unit. | 12-23-2010 |
20100226661 | WAVELENGTH DIVISION MULTIPLEXING TRANSMISSION SYSTEM AND APPARATUS AND OPTICAL SIGNAL NOISE RATIO CALCULATION METHOD - A wavelength division multiplexing (WDM) transmission system for transmitting a wavelength division multiplexed signal light from a sender transmission apparatus to a receiver transmission apparatus is provided. The system comprises a computing unit that subtracts from a first optical signal noise ratio (OSNR) of the signal light measured by the receiver transmission apparatus a second OSNR ascribed to a sideband of the signal light measured by the sender transmission apparatus so as to compute a corrected OSNR of an amplified spontaneous emission (ASE) noise light with a reduction of an effect of the sideband. | 09-09-2010 |