Abstract: A node device includes a processor, a wireless RF circuit, a memory, and a timer. The processor measures a clock time. The wireless RF circuit receives a clock time information frame containing clock time information used for correcting the clock time. The memory stores a transmission processing time period, as a fixed value, from when a transmission source node device of the clock time information frame obtains the clock time information until when the transmission source node device transmits the clock time information frame. The timer measures a reception processing time period, which is a period of time from when the clock time information frame is received until when the clock time information is obtained. The node device sets to the processor a value obtained by adding the fixed value and the reception processing time period to the clock time information.

Abstract: A node device includes a processor, a wireless RF circuit, a memory, and a timer. The processor measures a clock time. The wireless RF circuit receives a clock time information frame containing clock time information used for correcting the clock time. The memory stores a transmission processing time period, as a fixed value, from when a transmission source node device of the clock time information frame obtains the clock time information until when the transmission source node device transmits the clock time information frame. The timer measures a reception processing time period, which is a period of time from when the clock time information frame is received until when the clock time information is obtained. The node device sets to the processor a value obtained by adding the fixed value and the reception processing time period to the clock time information.

Abstract: A propagation apparatus includes a plurality of dispersion compensation execution units which accept a signal of a single wavelength from a wavelength-multiplexed signal which is received and execute dispersion compensation on the signal by inputting the accepted signal to a tunable dispersion compensator with an adjusted dispersion value, and a dispersion value calculation unit which acquires each dispersion value adjusted by the plurality of the dispersion compensation execution units, approximates the dispersion value of the wavelength assigned to a newly built line by using the acquired dispersion values whose signal error rates are in a tolerable range, and sets the approximated dispersion value as an initial value in the tunable dispersion compensator of the newly built line.

Abstract: An optical wavelength multiplexing system includes transmission-side and reception-side optical wavelength multiplexers, and terminal devices, which are connected to each other by optical fiber cables. Optical wavelength converters in the transmission-side optical wavelength multiplexers are connected to ports respectively. The optical wavelength converter converts an input optical signal into an arbitrary preset wavelength to generate a converted optical signal. The port has a predetermined wavelength preset therein. Each optical power level of input converted optical signals is compared with each optical power level of optical signals of respective wavelengths set in the ports. When a difference is detected in the comparison result, it is determined that an optical wavelength converter is incorrectly connected to the port.

Abstract: A measurement apparatus for measuring an optical fiber transmission line used to connect to an opposite apparatus, the measurement apparatus includes a transmission part for generating a measurement packet used for measuring a length of a first and second optical fiber transmission line, and transmitting the measurement packet to the opposite apparatus through the first optical fiber transmission line, a reception part for detecting the measurement packet returned from the opposite apparatus that perform a loopback processing of the measurement packet through the second optical fiber transmission line, a calculation part for calculating a packet transmission time which is a processing time required from the generation of the measurement packet to the detection of the measurement packet, and a measurement part for performing a measurement control of the length of the first and second optical fiber transmission line based on the packet transmission time calculated by the calculation part.

Abstract: A propagation apparatus includes a plurality of dispersion compensation execution units which accept a signal of a single wavelength from a wavelength-multiplexed signal which is received and execute dispersion compensation on the signal by inputting the accepted signal to a tunable dispersion compensator with an adjusted dispersion value, and a dispersion value calculation unit which acquires each dispersion value adjusted by the plurality of the dispersion compensation execution units, approximates the dispersion value of the wavelength assigned to a newly built line by using the acquired dispersion values whose signal error rates are in a tolerable range, and sets the approximated dispersion value as an initial value in the tunable dispersion compensator of the newly built line.

Abstract: An identification apparatus for identifying an optical passive device product. The apparatus includes an optical input output monitor section for monitoring an optical input and an optical output of the optical passive device product respectively; a loss calculation section for calculating a loss in the optical passive device product based on a monitoring result of the optical input output monitor section; and a product identification section in which product information indicating a correspondence between a loss characteristic and a product has been stored in advance, and which identifies the optical passive device product by comparing the stored product information and the loss calculated by the loss calculation section.

Abstract: A measurement apparatus for measuring an optical fiber transmission line used to connect to an opposite apparatus, the measurement apparatus includes a transmission part for generating a measurement packet used for measuring a length of a first and second optical fiber transmission line, and transmitting the measurement packet to the opposite apparatus through the first optical fiber transmission line, a reception part for detecting the measurement packet returned from the opposite apparatus that perform a loopback processing of the measurement packet through the second optical fiber transmission line, a calculation part for calculating a packet transmission time which is a processing time required from the generation of the measurement packet to the detection of the measurement packet, and a measurement part for performing a measurement control of the length of the first and second optical fiber transmission line based on the packet transmission time calculated by the calculation part.

Abstract: An apparatus comprises an optical level controller for autonomously controlling an optical device such that an optical level of the supplied optical signal becomes an objective level, and a controlled variable storer for storing a controlled variable in storage if a restart is required, the optical level controller providing the controlled variable to control the optical signal, wherein the optical level controller starts the control of optical device after the restart while the controlled variable stored in the storage by the controlled variable storer is set at an initial value.

Abstract: An identification apparatus for identifying an optical passive device product. The apparatus includes an optical input output monitor section for monitoring an optical input and an optical output of the optical passive device product respectively; a loss calculation section for calculating a loss in the optical passive device product based on a monitoring result of the optical input output monitor section; and a product identification section in which product information indicating a correspondence between a loss characteristic and a product has been stored in advance, and which identifies the optical passive device product by comparing the stored product information and the loss calculated by the loss calculation section.

Abstract: An optical wavelength multiplexing system includes transmission-side and reception-side optical wavelength multiplexers, and terminal devices, which are connected to each other by optical fiber cables. Optical wavelength converters in the transmission-side optical wavelength multiplexers are connected to ports respectively. The optical wavelength converter converts an input optical signal into an arbitrary preset wavelength to generate a converted optical signal. The port has a predetermined wavelength preset therein. Each optical power level of input converted optical signals is compared with each optical power level of optical signals of respective wavelengths set in the ports. When a difference is detected in the comparison result, it is determined that an optical wavelength converter is incorrectly connected to the port.

Abstract: An optical wavelength multiplex transmission apparatus includes a demultiplexer (12) that divides a wavelength-multiplexed optical signal into optical signals of individual wavelengths, an optical attenuation control portion (13) that performs an optical attenuation control so that levels of the optical signals of individual wavelengths become constant, a multiplexer (16) that combines the optical signals of individual wavelengths after the optical attenuation control and multiplexes them, an optical signal level storing portion (15) that stores a first level range of optical signal levels, and an optical attenuation control stopping portion (22) that decides whether or not a level of each of the optical signals of individual wavelengths is within the first level range obtained from the optical signal level storing portion (15), and if its level is within the first level range, stops the optical attenuation control for an optical signal of a wavelength having the level.

Abstract: A method for an intermediate node to control a level of a signal included in a wavelength-multiplexed signal and transmitted from a source node to a destination node via the intermediate node, includes: detecting a level of the signal; identifying a position of the intermediate node with respect to the source node; determining a control time based on the position; controlling, when the control time has elapsed from the detecting, a level of the signal based on the level detected at the detecting.

Abstract: A high-speed sprchronous multiplexing apparatus has a low-speed device and a high-speed device and employs electrical signals to interface the devices with each other. The low-speed device is connected to a low-speed digital circuit. The high-speed device is connected to a high-speed synchronous multiplexing circuit. The apparatus also has a clock supplier for supplying a reference clock signal that defines a communication rate, to each of the low- and high-speed devices. The apparatus further has an alarm processor for separating faults in the low- and high-speed devices. The low- and high-speed devices are interfaced with each other with the use of the reference clock signal and electrical STM-0/STS-1 signals that employ a frame signal synchronized with the reference clock signal.