| Patent application number | Description | Published |
|---|
| 20080205303 | FRAME TRANSMISSION APPARATUS - An apparatus including a first interface unit configured to perform frame communication processing with a ring network; a second interface unit configured to perform frame communication processing with a different network; a processing unit configured to convert a frame of a first format from the different network to a frame of a second format; a frame switching unit having at least one port connected to each of the first interface unit, the second interface unit and the processing unit and configured to switch the frame between ports; and a table configured to store frame identification information in correspondence with an output destination port identifier for an output port in the frame switching unit and frame conversion requirement information indicating whether conversion to the frame of the second format is required. | 08-28-2008 |
| 20080285976 | Optical signal demultiplexing device and optical signal demultiplexing method - An optical signal demultiplexing device includes a demultiplexing unit that receives an optical signal multiplexed by an optical time-division system and a synchronization pattern, and demultiplexes the optical signal based on the synchronization pattern. The optical signal demultiplexing device also includes a pulse-width increasing unit that makes optical signals demultiplexed by the demultiplexing unit generate chirp, and increases the pulse widths of the optical signals generating the chirp by passing the optical signals through a wavelength dispersion medium. | 11-20-2008 |
| 20090136239 | Optical Signal Transmission Control Apparatus and Optical Signal Transmission Control Method - An optical signal transmission control apparatus that controls transmission of optical signals transmitted via a plurality of redundant routes. The optical signal transmission control apparatus includes a delay difference adjusting unit that adjusts a transmission delay difference between the optical signals of each route by converting a wavelength of the optical signal and making the optical signal with a converted wavelength pass through a waveguide in which a transmission delay of the optical signal changes continuously depending on the wavelength, and a waveform degradation compensating unit that compensates degradation of a waveform of the optical signal, while maintaining the transmission delay difference adjusted by the delay difference adjusting unit. | 05-28-2009 |
| 20090207482 | Optical transmission system using raman amplifier and controlling method thereof - The optical transmission system modulates backward Raman pump light provided to an optical transmission line on one link side of an uplink and downlink, to thereby transmit a pilot signal for confirming a connection state of the optical transmission line to a node on an upstream side. When the pilot signal is received by the node on the upstream side, the backward Raman pump light provided to the optical transmission link on the opposite link side is modulated to thereby send back a response signal to an own node. Then by confirming receipt of the response signal at the own node, the backward Raman pump light provided to the optical transmission line on the one link side is changed over from a low output state to a high output state. | 08-20-2009 |
| 20090269079 | Optical signal transmission control apparatus and optical signal transmission control method - An optical signal transmission control apparatus that controls transmission of optical signals transmitted via a plurality of redundant routes. The optical signal transmission control apparatus includes a delay difference adjusting unit that adjusts a transmission delay difference between the optical signals of each route by converting a wavelength of the optical signal and making the optical signal with a converted wavelength pass through a waveguide in which a transmission delay of the optical signal changes continuously depending on the wavelength, and a waveform degradation compensating unit that compensates degradation of a waveform of the optical signal, while maintaining the transmission delay difference adjusted by the delay difference adjusting unit. | 10-29-2009 |
| 20090297154 | Transmission-path-type specifying apparatus and transmission-path-type specifying method - A transmission-path-type specifying apparatus includes an optical filter that extracts a plurality of different wavelength components from light including wavelength components occurring at the time of communication; an optical switch that simultaneously transmits same pulse signals superposed on light of the extracted wavelength components. The apparatus also includes an ASE modulation controlling unit that obtains a delay-time difference among the transmitted pulse signals when arriving at a destination via a transmission path; a characteristic-value calculating unit that calculates a characteristic value of the transmission path corresponding to a reference time varied depending on the obtained delay-time difference and a type of the transmission path; and a fiber-type determining unit that specifies the type of the transmission path based on the calculated characteristic value. | 12-03-2009 |
| 20100118387 | OPTICAL AMPLIFIER - An optical amplifier apparatus for amplifying a wavelength division signal light includes a detector for detecting an inputted wavelength division signal light, a dispersion compensator for compensating for a dispersion of the inputted wavelength division signal light, an optical amplifier for amplifying the inputted wavelength division signal light after compensation by stimulated emission of an optical gain medium including a rare-earth element, a propagation delay detector for detecting a propagation delay time of the wavelength division signal light between the detector and the optical amplifier, and a controller for controlling the gain of the optical amplifier on the basis of the propagation delay time such that the change of the gain of the optical amplifier is adjusted by the propagation delay time. | 05-13-2010 |
| 20100142940 | OPTICAL COMMUNICATION SYSTEM, OPTICAL RECEIVING TERMINAL, AND OPTICAL SIGNAL FAULT DETECTION METHOD - An optical communication system includes an optical transmission terminal including a first transmitter for transmitting an optical signal, and a second transmitter for transmitting information that indicates the first transmitter transmitting the optical signal; and an optical receiving terminal including an optical receiver for receiving the optical signal and the information transmitted from the first and second transmitter, respectively, a storage device for storing a power value of the optical signal monitored in response to receipt of the information transmitted from the second transmitter, and a fault detector for detecting fault of the optical signal by continuously monitoring a power value of the optical signal received by the optical receiver in comparison with the power value stored in the storage device. | 06-10-2010 |
| 20100260499 | OPTICAL TRANSMISSION APPARATUS - There is provided an optical transmission apparatus including: a plurality of wavelength selective switches including input ports, a transmission port, and monitor port used to output a light switched so that the light from the input port is monitored; a multiplexer to combine the lights output from the transmission ports of the plurality of wavelength selective switches; a monitor to monitor whether a same wavelength of the light output from the monitor port exists in wavelengths of the lights combined by the multiplexer; and a controller to control the wavelength selective switch so as to output, from the transmission port, the light switched to the monitor port in case that the same wavelength of the light output from the monitor port is absent in wavelengths of the lights combined by the multiplexer, based on a monitor result by the monitor. | 10-14-2010 |
