Patent application number | Description | Published |
20080239467 | OPTICAL AMPLIFIER - An optical amplifier including: a first amplifying unit amplifying an input light by utilizing a first excitation light and thereby outputting a first amplified light; a second amplifying unit amplifying the first amplified light by utilizing a second excitation light and thereby outputting a second amplified light; and a control unit detecting a first absorption rate of the first excitation light and a second absorption rate of the second excitation light, and controlling a level of the first excitation light and a level of second excitation light based on the first absorption rate and the second absorption rate. The first absorption rate corresponds to a ratio of the first excitation light absorbed in the first amplifying unit, and the second absorption rate corresponds to a ratio of the second excitation light absorbed in the second amplifying unit. | 10-02-2008 |
20080239470 | INDIVIDUAL BAND GAIN EQUALIZER FOR OPTICAL AMPLIFIERS - A control apparatus comprises a light monitoring unit for dividing a signal wavelength band into at least a band in which output light power of an optical amplifier tends to decrease at an decrease in the number of signal wavelengths and a band including a gain deviation band, and for monitoring inputted light power for the individual divided bands, a calculation unit for obtaining the number of signal wavelengths in the individual divided bands based on a monitor result, and a target gain correction unit for correcting a target gain based on a result of the calculation. This suppresses a transient variation of signal light level due to SHB or SRS at a high speed with a simple configuration without deteriorating noise characteristic, thus enabling optical amplifiers to be further disposed in a multi-stage fashion, which can lengthen the transmission distance of a transmission system including an optical add/drop unit. | 10-02-2008 |
20090206437 | Photo-detecting apparatus and photo-detecting method - A photo-detecting apparatus includes a photodiode that coverts light into electricity, a reverse-voltage switching unit that switches a reverse voltage to be applied to the photodiode, a current-difference detecting unit that detects a change in an output current of the photodiode occurring due to switching of the reverse voltage as a current difference, a correspondence retaining unit that retains a correspondence between the current difference and a dark current, a dark-current calculating unit that calculates a dark current by referring to the correspondence based on the current difference detected by the current-difference detecting unit, and a dark-current correcting unit that corrects the output current of the photodiode based on the dark current to find a photocurrent obtained through photoelectric conversion. | 08-20-2009 |
20090213455 | OPTICAL AMPLIFIER - An optical amplifier for amplifying light includes a light source for emitting pump light in accordance with current amount; a rear earth element doped optical fiber doped rear earth element, the rear earth element doped optical fiber pumped by the pump light from the light source; a detector for detecting upconversion light leaked from the rear earth element doped optical fiber; a memory for storing correspondence relationship data of the current amount for the light source and an intensity of the upconversion light in normal state of the light source; a difference calculator for calculating a difference between the intensity of the upconversion light being detected by the detector and a converted amount being converted the current amount for the light source by the use of the correspondence relationship data; and a discriminator for discriminating whether the difference calculated at the difference calculator exceeds a predetermined value. | 08-27-2009 |
20090219609 | Optical amplifier provided with control function of pumping light, and optical transmission system using the same - In an optical transmission system according to one aspect of the present invention, for transmitting a WDM light from a transmission station to a reception station, utilizing a Raman amplifier, the Raman amplifier comprises: an optical amplification medium; a pumping light source generating a plurality of pumping lights having wavelengths different from each other; an optical device introducing the plurality of pumping lights to the optical amplification medium; and control means for controlling the pumping light source, the transmission station sends out a plurality of reference lights having wavelengths at which respective Raman gain obtained by the plurality of pumping lights reach peaks or wavelengths close to the above wavelengths, and the control means controls the plurality of pumping lights based on the optical powers of the plurality of reference lights. Thus, it becomes possible to accurately manage the optical power balance of the WDM light and the optical power of the entire WDM light. | 09-03-2009 |
20090297143 | Optical transmission apparatus and optical attenuation amount control method - In an optical transmission apparatus, levels of signal lights obtained by demultiplexing a WDM signal and corresponding to channels are detected, based on which a channel in which a signal is transmitted and a channel in which no signal is transmitted are determined. An attenuation amount of a channel in which no signal is transmitted in a predetermined range from the channel in which the signal is transmitted is set to a value equal to an attenuation amount of the channel in which the signal is transmitted. An attenuation amount of a channel in which no signal is transmitted out of the predetermined range from the channel in which the signal is transmitted is set to a value larger than the attenuation amount of the channel in which the signal is transmitted. The signal lights are attenuated based on the values and multiplexed. | 12-03-2009 |
20100245988 | OPTICAL AMPLIFIER - An optical amplifier includes a first excitation light source that outputs a first excitation light; a second excitation light source that outputs a second excitation light; a first amplifying optical fiber doped with a rare-earth element and excited by the first excitation light to amplify light input to the first amplifying optical fiber; and a second amplifying optical fiber doped with a rare-earth element and excited by the second excitation light to amplify the light from the first amplifying optical fiber. A ratio between the intensity of the first excitation light and the intensity of the second excitation light is controlled according to the number of signal lights wavelength-multiplexed in the light input. | 09-30-2010 |
Patent application number | Description | Published |
20080222500 | Data relay apparatus, data relay method and data relay integrated circuit - According to an aspect of an embodiment, a data relay apparatus for transferring writing data and an associated check code sequentially sent from a host into a memory device, said writing data containing a plurality of fields classified by the kind of information in said writing data, comprising: a memory for storing said writing data and said check code for checking an error of said writing data; a calculating module for calculating said check code to determine whether the writing data sent from the host contains an error; a transfer module for transferring the writing data into the memory, the transferring of the writing data into the memory being initiated before determination by the calculating module. | 09-11-2008 |
20100235684 | STORAGE SYSTEM, ADAPTER, AND DIAGNOSIS PROCESSING METHOD - A storage system for controlling a storage device to store data from a host system, the storage system includes a storage controller for controlling to write to or read data from the storage device, a memory for temporally storing data during performing a data relay processing between the host system and the storage device, and a relay device for performing the data relay processing using the memory. The relay device includes a plurality of processing circuits for performing the data relay processing cooperatively and a self-diagnosis controller for controlling each of the processing circuits to start independently a self-diagnosis processing upon completion of the processing by each of the processing circuit. | 09-16-2010 |
20100299565 | CONTROLLING APPARATUS AND CONTROLLING METHOD - A controlling apparatus for controlling a disk array unit includes a cache memory for caching data of the disk array unit; a nonvolatile memory for storing the data in the cache memory; and a control unit for detecting a defective location in the nonvolatile memory where the data is stored defectively and updating information indicating the defection location, for generating an error detection code of the updated information, for writing the generated information and the associated error detection code into an area of the nonvolatile memory different from any area where any information indicating any defective location previously detected and stored into the nonvolatile memory, and for controlling writing the data in the cache memory into a location of the nonvolatile memory designated by any selected one of the information stored in the nonvolatile memory. | 11-25-2010 |
20100318844 | BACKUP METHOD AND DISK ARRAY APPARATUS - A backup method makes a backup of cache data to a nonvolatile memory by using a controller, the cache data being stored in the volatile memory. The backup method includes writing the cache data stored in the volatility memory in a selected area of the nonvolatile memory, generating party data by operating the parity operations between each of the predetermined parts of the cache data in the volatile memory, verifying whether an error found in the part of the cache data in the nonvolatile memory can be recovered by using the parity data, and rewriting the part of the cache data when the error found in the part of the cache data in the nonvolatile memory cannot be recovered by using the parity data in an area of the nonvolatile memory different from the selected area. | 12-16-2010 |