Abstract: An optical packet switch device includes an optical switch control section and an optical switch section. The optical switch control section includes a synchronization pattern detecting unit which detects a frame synchronization pattern from a parallel data signal and detects a delay bit number showing that the frame synchronization pattern is stored at a position shifted by how many bits from the first bit of the parallel data signal, a header analysis unit which analyzes a header and detects an optical packet length and route information of an optical packet signal, and an output competition determining unit which determines passing/discarding of the optical packet signals competing with each other based on the optical packet length and the route information detected by the header analysis unit and delay bit number information detected by the synchronization pattern detecting unit.

Abstract: 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.

Abstract: An optical packet switching apparatus includes an optical coupler for branching off a received optical packet signal, an optical switch unit for switching the route of one of the branched-off optical packet signals so as to be outputted, and an optical switch control unit for controlling the optical switch unit. The optical switch control unit includes an optical-to-electrical conversion unit for converting the other of the branched-off optical packet signals into an electrical packet signal, a serial/parallel conversion unit capacitively coupled to the optical-to-electrical conversion unit, a packet density detector for detecting the packet density of the received packet signal, and a DC offset adjustment unit for adjusting the DC offset voltage of the packet signal, inputted to the serial/parallel conversion unit, according to the packet density information detected by the packet density detector.

Abstract: An optical packet switching system includes: an optical packet transmitter device configured to transmit an optical packet signal; and an optical packet switching device configured to route and output an input optical packet signal. The optical packet transmitter device is configured to adjust gap time between optical packets transmitted. The optical packet transmitter device adjusts the gap time to a fixed value defined by time required for switching in the optical packet switching device.

Abstract: An optical packet switching apparatus includes (i) an optical packet switch for switching the route of an inputted optical packet signal and outputting the inputted optical packet signal, (ii) an input-side packet density monitoring unit for detecting the packet density of optical packet signals inputted to the optical packet switch, (iii) a first input-side optical amplifier provided on an input side of the optical packet switch, (iv) a first input-side variable optical attenuator (VOA) provided posterior to the optical amplifier, (v) a storage for storing the gain characteristics in relation to the packet density at the first input-side optical amplifier, and (vi) an input-side VOA control unit for controlling the attenuation by the first input-side VOA in such a manner as to compensate for the gain fluctuations due to the variations in the packet density at the first input-side optical amplifier, based on the packet density and the gain characteristics.

Abstract: An optical packet switching apparatus includes an optical switch unit for switching the route of a received optical packet signal and output the received optical packet signal, and an optical switch control unit for extracting destination information from the received optical packet and generating a control signal for the optical switch unit according to the destination information. The optical switch control unit includes a clock generator for generating a plurality of local clocks of different phases, and a clock selector for selecting a local clock having the smallest phase difference with the received optical packet from the plurality of local clocks. The optical switch control unit generates the control signal using the local clock selected by the clock selector as an operation clock.

Abstract: 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.

Abstract: An optical packet switching system includes: an optical packet switching device configured to route and output an input optical packet signal; an optical amplifier device provided in a stage subsequent to the optical packet switching device; and a dummy packet insertion device configured to insert a dummy packet in an optical packet signal prior to input to the optical amplifier device. A dummy packet includes a flag indicating that the packet is a dummy packet.

Abstract: Provided is a wavelength division multiplexing transmission apparatus that enables operation control of transponders each carrying an FBTL optical module from the monitoring control unit by the same operation control as one for the transponders each carrying an NB optical module with four wavelengths assigned. For that purpose, the wavelength division multiplexing transmission apparatus includes the transponders for converting optical signals from wideband wavelengths to narrowband wavelengths, and a monitoring control unit for controlling the transponders by instructions from an operator.

Abstract: The present invention relates to a chuck mechanism of a charge/discharge testing device for flat-rechargeable batteries and has a proposition to provide a chuck mechanism that makes it possible to lighten conventionally needed troublesome works, that is, for example, works of storing and fixing a large number of flat-rechargeable batteries in a container, and that is capable of surely chucking the flat-rechargeable batteries (electrodes).

Abstract: 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.

Abstract: 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.

Abstract: A layer 2 switch (L2SW) includes (i) a learned 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.

Abstract: An optical packet switching apparatus includes an optical coupler, an optical switch unit, and an optical switch control unit. The optical switch control unit includes an optical-to-electrical converter, a serial/parallel converter, an arrangement detector, a rearrangement unit, a frame synchronization unit, a route detector, a control signal generator, and an adjustment unit for adjusting the timing with which to output an optical switch control signal to the optical switch unit, based on arrangement information on a frame synchronization pattern fed from the arrangement detector.

Abstract: 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.

Abstract: 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

Abstract: 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.

Abstract: 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 1G-ONUs and each of 10G-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.

Abstract: 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.

Abstract: 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.