摘要:
A dispersion compensating method for compensating wavelength dispersion occurring in an optical transmission line, includes the steps of: a) performing dispersion compensation by causing an optical signal, supplied from the transmission line, to pass through a variable dispersion compensator; and b) controlling a dispersion compensating amount in the variable dispersion compensator according to code error information corresponding to a type of code in a received data signal obtained from receiving the optical signal having undergone the dispersion compensation.
摘要:
A power-down delay unit 15 for delaying cutoff of a voltage is provided in the power supply line for supplying power to an optical module 14 of a transponder unit 16 of each wavelength. The power-down delay unit 15 assigns a different delay in power disconnection each wavelength. The length of the delay is a time required by an AMP unit or longer to change from an ALC mode to an AGC mode. With the configuration, when the power supply for supplying power to the plurality of transponder units 16 becomes faulty and output of a number of wavelengths simultaneously stops, the actual optical signal gradually stops output wavelength by one wavelength. Thereby a nonlinear effect because of going up of a power of an optical signal too much is not occurred, therefore it is able to prevent an undesired influence for a wavelength not to be stopped.
摘要:
A power-down delay unit for delaying cutoff of a voltage is provided in a power supply line which supplies electrical power to an optical module of a transponder unit for each optical wavelength. The power-down delay unit assigns different delays for each wavelength. The length of the delay is a time required by an AMP unit to change from an ALC mode to an AGC mode or longer. When the power sources for supplying electrical power to the transponder units becomes faulty and outputs of several wavelengths are simultaneously going to stop, the power-down delay unit delays cutoff of the supply voltage to the optical modules by keeping supply voltage for a while to the optical modules on behalf of power sources enabling the optical modules to operate after the power sources shutdown, so that the actual optical signals gradually stop one by one.
摘要:
A frame transmitting apparatus that transmits a frame including data to be transmitted or a frame including control data for a data-transmission control via a network includes a frame generating unit that generates a frame including identification-information-added data to which 1-bit identification information indicating whether a block obtained by dividing data into every n bits includes the control data is added, where n is a positive integer, and an error control code for a data-transmission error control; and a frame transmitting unit that transmits the frame generated.
摘要:
A dispersion compensating method for compensating wavelength dispersion occurring in an optical transmission line, includes the steps of: a) performing dispersion compensation by causing an optical signal, supplied from the transmission line, to pass through a variable dispersion compensator; and b) controlling a dispersion compensating amount in the variable dispersion compensator according to code error information corresponding to a type of code in a received data signal obtained from receiving the optical signal having undergone the dispersion compensation.
摘要:
An optical transmission apparatus that improves the reliability of system operation by efficiently limiting the line speed of a signal sent from a user with a guard mechanism. An optical branching section makes an optical signal branch in two directions. A through branching line passes an optical signal in its original condition and sends the optical signal as a through optical branch signal. A delay branching line delays an optical signal by a delay amount set and sends the optical signal as a delayed optical branch signal. An optical multiplexing section combines the through optical branch signal and the delayed optical branch signal. A line speed limitation section limits acceptance of the line speed of the optical signal inputted by generating a multiplexed optical signal that meets a pulse mask standard for an optical signal to be passed for the optical signal which is sent at a line speed lower than or equal to a line speed settled under contract with a user and which is to be passed and by setting the delay amount for generating a multiplexed optical signal that does not meet a pulse mask standard for an optical signal acceptance of which is to be refused for the optical signal which is sent at a line speed higher than the line speed settled under contract with the user and acceptance of which is to be refused.
摘要:
An optical transmission apparatus that improves the reliability of system operation by efficiently limiting the line speed of a signal sent from a user with a guard mechanism. An optical branching section makes an optical signal branch in two directions. A through branching line passes an optical signal in its original condition and sends the optical signal as a through optical branch signal. A delay branching line delays an optical signal by a delay amount set and sends the optical signal as a delayed optical branch signal. An optical multiplexing section combines the through optical branch signal and the delayed optical branch signal. A line speed limitation section limits acceptance of the line speed of the optical signal inputted by generating a multiplexed optical signal that meets a pulse mask standard for an optical signal to be passed for the optical signal which is sent at a line speed lower than or equal to a line speed settled under contract with a user and which is to be passed and by setting the delay amount for generating a multiplexed optical signal that does not meet a pulse mask standard for an optical signal acceptance of which is to be refused for the optical signal which is sent at a line speed higher than the line speed settled under contract with the user and acceptance of which is to be refused.
摘要:
A cylindrical heat generating belt in an image heating apparatus includes a heat generating layer, in which an electroconductive filler is dispersed in a resin material, for generating heat by being supplied with electric power; and a surface parting layer. The heat generating layer has a sheet resistance, with respect to a generatrix direction of the heat generating belt, which is larger than that with respect to a circumferential direction of the heat generating belt.
摘要:
An image forming apparatus includes an image forming station for forming a toner image on a recording material; and a fixing portion including a heating rotatable member, a heating element for heating the heating rotatable member using heat generation by electric power supply, a pressing rotatable member for contacting the heating rotatable member to form a nip for nipping and feeding the recording material, a pressure changing member for changing a pressure to the nip, wherein the fixing portion fixes the toner image on the recording material while nipping and feeding the recording material carrying the toner image by the nip, and fixing portion is capable of changing a glossiness of the toner image by changing the pressure to the nip by operation of the pressure changing member, wherein the image forming apparatus is operable in a glossy mode in which the glossiness of the toner image is switchable, wherein a MD-1 hardness of a surface layer of the heating rotatable member contactable with the toner image is 20-70, and when the glossy mode is selected so as to raise the glossiness at the time of heating and fixing of the toner image, the pressure changing member operates so as to lower the pressure to the nip.
摘要:
In an image heating apparatus, outer peripheral surfaces of two endless belts are held in contact with each other to form a nip portion, and a recording material bearing a toner image is heated at the nip portion while being pinched and conveyed. In the image heating apparatus, the nip portion has a pre-nip portion formed by regions of the endless belts with no backup by pressure members, and a pressure nip portion where one endless belt with backup by the pressure members is held in contact with another endless belt. The image heating apparatus is capable of securing a large nip width compatible with an increase in speed and free from “pressure-absence” leading to image abnormality such as misregistration, thus enabling an image having a sufficient gloss to be obtained.