Abstract: A transmission apparatus includes: an assigning unit that assigns an information signal to a subcarrier with a frequency different from a frequency of a received radio signal; a creating unit that creates a multi-carrier signal, in which information signals are multiplexed, each of the information signals being assigned to one subcarrier by the assigning unit; and a multiplexing unit that frequency-multiplexes the received radio signal to the multi-carrier signal created by the creating unit and outputs a resulting frequency-multiplexed signal.

Abstract: An optical reception apparatus may include a receiver, a monitor, and a controller. The optical reception apparatus receives multi-carrier modulated signal light modulated by a multi-carrier modulation scheme. The multi-carrier modulation scheme is available to allocate different transmission conditions for each of a plurality of subcarriers in accordance with transmission characteristics of the subcarriers. The receiver may receive from an optical transmission line a training signal light allocated with the same transmission conditions for each of the subcarriers. The monitor may monitor the transmission characteristics of the training signal light to detect a frequency at which a dip of the transmission characteristics occurs. The controller may control, based on the frequency detected by the monitor, a dispersion compensation for the multi-carrier modulated signal light having received a dispersion from the optical transmission line.

Abstract: Problem: To provide: a cell wherein a supporting body is able to have a small open porosity even in cases where the firing temperature is low; a cell stack device; a module; and a module-containing device. Resolution means: A cell (10) according to the present invention is obtained by arranging, on a porous supporting body (1), a porous fuel electrode layer (3), a dense solid electrolyte layer (4) that is formed of a ceramic, and a porous oxygen electrode layer (6) in this order. The amount of Na in the supporting body (1) is 30×10?6 mass % or less. Another cell (10) according to the present invention is obtained by arranging, on a porous supporting body (1) that serves as a first electrode layer, a dense solid electrolyte layer (4) that is formed of a ceramic and a porous oxygen electrode layer (6) in this order. The amount of Na in the supporting body (1) is 30×10?6 mass % or less.

Abstract: An optical transmitter includes a DMT modulating unit that allocates information signals to SCs and that generates a DMT signal by performing multi-level modulation on each of the information signals allocated to each of the SCs. The optical transmitter includes a mixer that shifts, on the basis of the probe result of the DMT signal and frequency information on a wireless signal that is input, the carrier frequency of the wireless signal so as not to overlap the SC to which the information signal in the DMT signal is allocated. Furthermore, the optical transmitter includes a multiplexing unit that multiplexes the DMT signal received from the DMT modulating unit and the wireless signal in which the carrier frequency has been shifted and outputs the multiplexed signal.

Abstract: A transmission device includes: a plurality of modulators that respectively generate multicarrier signals from given data; a distributor that distributes input data to the modulators; an optical circuit that multiplexes the multicarrier signals to generate a WDM optical signal; and a controller that obtains allocation information from a receiver of the WDM optical signal and generates a distribution instruction to control the distributor and a bit allocation instruction to control the modulators according to the allocation information. The allocation information is calculated based on transmission characteristics of each subcarrier of the respective multicarrier signals and the allocation information indicates a number of bits of data allocated to each of the subcarriers. The distributor distributes the input data to the modulators according to the distribution instruction.

Abstract: An optical transmitter includes: an optical modulator configured to generate an optical signal from a plurality of transmission signals; a crosstalk monitor configured to monitor crosstalk between the plurality of transmission signals by using the optical signal; and a crosstalk canceller configured to correct the plurality of transmission signals based on a result of monitoring by the crosstalk monitor.

Abstract: An optical transmitter includes a discrete multi-tone (DMT) modulation unit that modulates a carrier signal having a specific frequency with an information signal and a carrier signal having a frequency different from the specific frequency with a monitor signal, to generate a DMT modulation signal that multiplexes the information signal and the monitor signal. The optical transmitter includes a laser diode (LD) unit that optically converts the DMT modulation signal to a corresponding optical DMT modulation signal, a frequency extraction unit that extracts a harmonic distortion component of the monitor signal from the optical DMT modulation signal, and a frequency analysis unit. The optical transmitter includes a bias control unit that controls a bias supply unit that adjusts a bias value to be supplied to the LD unit such that the extracted harmonic distortion component of the monitor signal is reduced.

Abstract: A transmission control device includes a subcarrier selector configured to select one or more subcarriers for transmitting an error correction code for correcting data, from a plurality of subcarriers having different transmission capacities, each of the plurality of subcarriers used for transmitting either of the data and the error correction code, in accordance with an amount of data of the error correction code and transmission capacities respectively assigned to the plurality of subcarriers.

Abstract: An optical transmission device includes: an error correction scheme determining unit configured to determine an error correction scheme based on a latency between the optical transmission device and a correspondent device; an error correction encoder configured to generate encoded data by performing an error correction encoding on transmission data using the error correction scheme determined by the error correction scheme determining unit; a modulation format determining unit configured to determine a modulation format based on the error correction scheme determined by the error correction scheme determining unit and transmission characteristics between the optical transmission device and the correspondent device; and an optical transmitter configured to generate a modulated optical system from the encoded data with the modulation format determined by the modulation format determining unit.

Abstract: A PON (Passive Optical Network) system, which modulates multiple subcarriers with data of multiple users to output an optical multiplexed signal from a station device, splits the optical multiplexed signal to transmit the split signals to multiple subscriber devices that are provided for each of the users, and demodulates the data of the users at the respective subscriber devices, includes: an obtaining section configured to obtain a transmission characteristic for each of the subcarriers at each of the subscriber devices, by receiving a test signal at the subscriber devices, which is transmitted from the station device; and an assigning section configured to assign one or more of the subcarriers for each of the subscriber devices suited to the transmission characteristics of the assigned subcarriers at each of the subscriber devices.

Abstract: A multilevel-intensity modulation and demodulation system includes: a digital-to-analog conversion unit to convert an output level value of a digital signal into an analog signal; a multilevel-intensity-modulated light transmission unit to transmit an optical signal multilevel-intensity modulated based on the analog signal; a multilevel-intensity-modulated light reception unit to receive the optical signal multilevel-intensity modulated, and convert the received optical signal into an analog reception electrical signal; an analog-to-digital conversion unit to convert the analog reception electrical signal into a reception level value; and a controller to convert a transmission multiple gradation level being one of a plurality of multiple gradation levels of multilevel-intensity modulation to which the digital signal is mapped, into the output level value so as to cause the reception level value to be in a desired reception state, and to receive a digital signal corresponding to a reception multiple-gradation-

Abstract: A transmitting apparatus is used in an electrical frequency division multiplex transmission system including nodes that are on an optical transmission path and that respectively frequency-multiplex a sub-carrier of a unique frequency and a carrier wave to transmit information to a receiving apparatus on the optical transmission path. The transmitting apparatus is disposed in each node and includes a determining unit that receives an input of information concerning unused sub-carriers of a transmission signal in the optical transmission path and determines transmission of the information to the receiving apparatus using an unused sub-carrier; an electrical frequency division multiplex transmission unit that using a frequency of the unused sub-carrier determined by the determining unit, modulates the input information to be transmitted to the receiving apparatus; and a coupling unit that adds to the transmission signal in the optical transmission path, a modulated modulation signal.

Abstract: A transmission apparatus includes: an assigning unit that assigns an information signal to a subcarrier with a frequency different from a frequency of a received radio signal; a creating unit that creates a multi-carrier signal, in which information signals are multiplexed, each of the information signals being assigned to one subcarrier by the assigning unit; and a multiplexing unit that frequency-multiplexes the received radio signal to the multi-carrier signal created by the creating unit and outputs a resulting frequency-multiplexed signal.

Abstract: An optical transmitter includes: a digital signal process unit that generates a drive signal for generating multi-carrier signals through a plurality of independent digital signal processes, the multi-carrier signals having a cyclic prefix and to be transmitted by a parallel transmission; a synchronization unit that synchronizes clocks of the plurality of digital signal processes; and an adjust unit that reduces a delay difference of the cyclic prefix between the multi-carrier signals after the parallel transmission.

Abstract: An optical transmitter converts a plurality of transmission signals transmitted via a plurality of lanes into a multi-carrier signal and transmits the multi-carrier signal. The optical transmitter includes: a controller configured to generate allocation information that indicates an allocation of sub-carriers to the plurality of lanes according to a bit rate of the transmission signal of each of the lanes and a possible transmission capacity of each of the sub-carriers; and a signal processor configured to convert the plurality of transmission signals into the multi-carrier signal in accordance with the allocation information generated by the controller.

Abstract: A method for suppressing a skew between a first channel and a second channel in an optical transmission system having a transmitter that transmits an optical signal with the first channel and the second channel and a receiver that receives the optical signal, the method includes: controlling dispersion added to the optical signal to be larger than a specified amount; and controlling a delay time of at least one of the first channel and the second channel in the receiver based on a quality of the optical signal monitored in the receiver to suppress the skew between the first channel and the second channel in the receiver.

Abstract: An optical amplifier includes a pump light source that outputs pump light, and a multicore fiber that includes at least one pumping core, the pump light being input to the at least one pumping core by coupler, at least two signal light cores doped with an active substance for optical amplification, at least one signal light being input to at least one of the signal light cores, and a cladding, wherein the pump light propagating the at least one pumping core and exciting the active substance in the signal light cores, so as to amplify the at least one signal light propagating through the at least one of the signal light cores.

Abstract: A transmission control device includes a subcarrier selector configured to select one or more subcarriers for transmitting an error correction code for correcting data, from a plurality of subcarriers having different transmission capacities, each of the plurality of subcarriers used for transmitting either of the data and the error correction code, in accordance with an amount of data of the error correction code and transmission capacities respectively assigned to the plurality of subcarriers.

Abstract: An optical signal transmitting apparatus is disposed in an optical frequency division multiplex transmission system that includes plural nodes that are in an optical transmission path and respectively use a unique frequency to frequency-multiplex information with a carrier wave to transmit the information to an optical signal receiving apparatus in the optical transmission path. The optical signal transmitting apparatus outputs the carrier wave and includes a transmitting unit into which information to be delivered to the nodes is input, the transmitting unit transmitting the information using a frequency that does not overlap the unique frequencies used by the nodes; and a multiplexing unit that frequency-multiplexes output of the transmitting unit and the carrier wave, and sends the frequency-multiplexed output to the optical transmission path.

Abstract: A transmitting apparatus is used in an electrical frequency division multiplex transmission system including nodes that are on an optical transmission path and that respectively frequency-multiplex a sub-carrier of a unique frequency and a carrier wave to transmit information to a receiving apparatus on the optical transmission path. The transmitting apparatus is disposed in each node and includes a determining unit that receives an input of information concerning unused sub-carriers of a transmission signal in the optical transmission path and determines transmission of the information to the receiving apparatus using an unused sub-carrier; an electrical frequency division multiplex transmission unit that using a frequency of the unused sub-carrier determined by the determining unit, modulates the input information to be transmitted to the receiving apparatus; and a coupling unit that adds to the transmission signal in the optical transmission path, a modulated modulation signal.