Abstract: The communication apparatus includes a logical device, a wiring line, and a changing unit; the logical device is a programmable device; the wiring line supplies a voltage to the logical device; and the changing unit changes a frequency characteristic of the wiring line based on an operating characteristic obtained by monitoring of the operating characteristic of the logical device for operating by receiving supply of the voltage. According to this, occurrence of voltage drop can be suppressed even if a circuit configured in a programmable logical device is changed.

Abstract: A transmission apparatus includes a memory and a circuit. The memory store control data included in a frame received from outside the apparatus and state information indicating a state of the control data in the transmission apparatus in association with each other. The circuit records the control data included in the frame to the memory. The circuit changes the state information to information indicating that the recording of the control data is completed. The circuit determines whether or not the control data stored in the memory is to be rewritten. The circuit rewrites the control data stored in the memory, upon determining that the control data is rewritten. The circuit changes the state information to information indicating that the rewriting of the control data is completed. The circuit reads the control data stored in the memory.

Abstract: An optical amplifier apparatus includes an optical amplifier including an amplification medium doped with an active substance, the amplification medium excited in order to amplify light; a semiconductor optical amplifier arranged after the optical amplifier; a driver for supplying a driving current with respect to the semiconductor optical amplifier in order that the semiconductor optical amplifier has an amplification characteristic with respect to an input light, the amplification characteristic including a gain non-saturated region and a gain saturated region; and an input-light level adjuster for adjusting an out put light of the optical amplifier to the input light level of the semiconductor optical amplifier, the input light level being set up between the gain non-saturated region and the gain saturated region.

Abstract: An aspect of the embodiments utilizes an optical transmission apparatus which includes a rough adjustment execution portion that monitors a bit error rate of an optical signal for set values of a dispersion compensator where the set values have been set less closely to each other within a dispersion compensation control range than when a wavelength dispersion value set in the dispersion compensator is determined, and carries out a rough adjustment to determine a comparison threshold value used to set the wavelength dispersion value based on the monitored bit error rate, and a fine adjustment execution portion that monitors the bit error rate for the dispersion compensator the set values have been set more closely to each other, and carries out an adjustment to determine a wavelength dispersion value corresponding to the midpoint between the two acquired bit error rates as the wavelength dispersion value of the dispersion compensator.

Abstract: A transmission apparatus includes a memory and a circuit. The memory store control data included in a frame received from outside the apparatus and state information indicating a state of the control data in the transmission apparatus in association with each other. The circuit records the control data included in the frame to the memory. The circuit changes the state information to information indicating that the recording of the control data is completed. The circuit determines whether or not the control data stored in the memory is to be rewritten. The circuit rewrites the control data stored in the memory, upon determining that the control data is rewritten. The circuit changes the state information to information indicating that the rewriting of the control data is completed. The circuit reads the control data stored in the memory.

Abstract: An aspect of the embodiments utilizes an optical transmission apparatus which includes a rough adjustment execution portion that monitors a bit error rate of an optical signal for set values of a dispersion compensator where the set values have been set less closely to each other within a dispersion compensation control range than when a wavelength dispersion value set in the dispersion compensator is determined, and carries out a rough adjustment to determine a comparison threshold value used to set the wavelength dispersion value based on the monitored bit error rate, and a fine adjustment execution portion that monitors the bit error rate for the dispersion compensator the set values have been set more closely to each other, and carries out an adjustment to determine a wavelength dispersion value corresponding to the midpoint between the two acquired bit error rates as the wavelength dispersion value of the dispersion compensator.

Abstract: An optical amplifier apparatus includes an optical amplifier including an amplification medium doped with an active substance, the amplification medium excited in order to amplify light; a semiconductor optical amplifier arranged after the optical amplifier; a driver for supplying a driving current with respect to the semiconductor optical amplifier in order that the semiconductor optical amplifier has an amplification characteristic with respect to an input light, the amplification characteristic including a gain non-saturated region and a gain saturated region; and an input-light level adjuster for adjusting an out put light of the optical amplifier to the input light level of the semiconductor optical amplifier, the input light level being set up between the gain non-saturated region and the gain saturated region.