Abstract: When a terminal station receives a beacon in a channel f(i), it registers a MAC address included in the beacon in a registration table with an association with the channel f(i), then registers channels in which the same MAC address is registered, and the number of the channels in the registration table. By this processing, channels usable in a base station and the number of the channels usable are designated without need of adding, to a packet, information indicating the channels usable and the number of the channels usable.

Abstract: A method for correcting a soft decision value includes: demodulating a reception signal, which is coded by an error correction code and modulated in order to represent one or multiple bits with one symbol; generating the soft decision value, which is used in decoding of the error correction code; multiplying the soft decision value by a weight factor to correct the soft decision value; estimating an amplitude of the reception signal in every predetermined measurement time period; and variably setting the weight factor in a symbol unit in accordance with an estimating result so that a corrected soft decision value approaches to a predetermined amplitude range.

Abstract: A receiver device for a packet communication system receives a packet signal appended at its head with a known number (N) of repetition signals. A correlation value of a received signal is outputted from a normalizing correlator and compared with a threshold value in a comparator. The output of the comparator is inputted to a synchronization signal generating circuit, which includes M (?N?1) delay elements connected in series and an AND circuit for taking the logical product of the outputs of the delay elements. When the output of the comparator is high-level and the outputs of the M delay elements 431 are also all high-level, a synchronization signal at symbol timing is outputted from the AND circuit.

Abstract: A vehicle-vehicle communication system includes an in-vehicle wire LAN established in a vehicle. The in-vehicle wire LAN includes a plurality of devices connected by optical fiber links. A terminal for radio vehicle-vehicle communication is connected to the in-vehicle wire LAN by the optical fiber link. The terminal receives an optical digital signal in a predetermined format from the in-vehicle wire LAN. The terminal includes a light controlled oscillator and applies the received optical signal to the light controlled oscillator. The light controlled oscillator outputs a transmission signal of a frequency shifted from a predetermined frequency according to the intensity of the applied optical signal. Thus the terminal generates the transmission signal using FSK-modulation technique without converting the format of the optical signal into another format. The transmission signal is transmitted to a device in another vehicle via radio waves.

Abstract: In a communication system, a content server reads required data from a content database and transmits the data by packet communications over public communication lines, and a network management server receives and stores the required information from the public communication lines. The network management server sends the temporarily stored data to plural transmitter stations. Each transmitter station has a corresponding dividing device. Each dividing device receives and relays to the linked transmitter station only the amount of data required for transmission to the linked transmitter station. The remaining data is simply passed by the dividing device to the next dividing device without processing the data in any way.

Abstract: A diversity OFDM communication is performed between a base terminal and a mobile terminal, both having a horizontal polarization antenna and a vertical polarization antenna forming two transmission channels. In the base terminal, data signals to be transmitted are divided into two channels to transmit the data signals through either one of the channels having a higher transmission performance for each sub-carrier. Common pilot signals are transmitted through both channels. The data signals received by the mobile terminal are phase-adjusted using the common pilot signals. The phase-adjusted data signals in both channels are synthesized and then demodulated.

Abstract: Communication between a stationary terminal such as an on-road terminal and a mobile terminal mounted on an automotive vehicle is performed under an OFDM system. Before transmitting data signals from the mobile terminal to the stationary terminal, a control signal indicating the number of sub-carries used in the data transmission is sent to the stationary terminal. The number of sub-carriers is decreased in accordance with increase of the moving speed to avoid deterioration in communication quality due to the moving speed increase. A modification formula and/or an error-correction-code coding rate used in the data transmission may be varied according to the moving speed in place of or together with varying the number of sub-carriers.

Abstract: A receiving section outputs a received signal. An estimation section estimates transmission path characteristics, using the received signal and a modulated data signal. A compensation section outputs a compensated data signal, using the received signal and the transmission path characteristics. A demodulation section demodulates a modulated data signal, using the compensated data signal. A modulation section modulates a modulated data signal, using the demodulated data signal. The estimation section begins the estimation by comparing a result obtained by modulating known-data and a known-data portion of the received signal. The compensation section compensates for a non-compensated data signal portion, using the estimated transmission path characteristics.

Abstract: A Micro-cell is formed to include a plurality of spot-cells. Communication is executed between a micro-cell base station and a mobile terminal in the micro-cell, and between a spot-cell base station and the mobile terminal in the spot cell. The micro-cell base station and spot-cell base stations are connected to an integrated base station. A signal transmitted to the micro-cell base station from the mobile terminal is transferred to the integrated base station and information transmitted to the mobile terminal is transferred to the micro-cell base station and/or spot-cell base station from the integrated base station. The respective integrated base stations are connected to a server via a dedicated backbone to enable a large-capacity transmission.

Abstract: A channel evaluator acquires a change predicted value from a known symbol, and a compensator compensates for a first symbol using the change predicted value. A demodulator restores a portion corresponding to this symbol with another subcarrier. A replica generator acquires a transmission replica of the restored symbol. The channel evaluator performs complex division on the replica with the symbol to acquire an amplitude phase ratio. A detector compares the amplitude phase ratio with an amplitude phase ratio acquired immediately previously. In case where an elimination condition is satisfied, the detector disregards the amplitude phase ratio acquired currently and uses an immediately previous value instead, an averaging unit averages amplitude phase ratios to acquire a next change predicted value, and the compensator compensates for a next symbol using the change predicted value. Hereinafter, the sequence of processes is repeated.

Abstract: After the OFDM signal for MMAC is received by a receiving unit , an FFT processing unit converts such OFDM signal into the signal Y(l, k) in the frequency axis direction. A data extracting unit extracts a data signal Y(l, kd) and a pilot extracting unit extracts a pilot signal Y(l, kp). A complex dividing unit divides the extracted pilot signal with a pilot signal X(l, kp) having the identical amplitude and phase as that in the transmitting side. An interpolating unit performs a linear interpolation by using a transmission path response H(l, kp) of the pilot signal in order to calculate the transmission path estimation value H?(l, k) of the data signal. A complex dividing unit divides the extracted data signal with the transmission path estimation value of the data signal in order to calculate the data signal Y?(l, kd) that is compensated in the amplitude and phase.

Abstract: A packet signal, formed according to an orthogonal frequency division multiplexing (OFDM) format, received by a receiver is decoded in a decoder device of the receiver. The packet signal includes a data code and a control code having a formula for decoding the data code. The control code is first decoded and analyzed to obtain the decoding formula contained therein. The data code is decoded during a period in which the control code is being analyzed, based on plural decoding formulae one of which coincides with the decoding formula contained in the control code. Data signals decoded based on the respective decoding formulae are sent to an output selector together with the decoding formula obtained from the control code. The output selector selects a data signal which is decoded based on a decoding formula that coincides with the decoding formula obtained from the control code.

Abstract: In a radio communication system, a base station sends each of n send packets to a terminal station in parallel through n channels as they are in packet unit instead of dividing each of n send packets to send the same to the terminal station. It is possible in the base station to eliminate the need for a processing of dividing send packets and processing of resending divided send packets. It is also possible in the terminal station to eliminate the need of a configuration for receiving the divided send packets.

Abstract: An electrophotographic positively charged toner and method for its manufacture. The toner includes a core toner that has a binder resin, a wax, a colorant and a charge control agent as its principal component materials. The core toner is spherified through heat treatment. The toner also includes at least fine silica particles as an external additive. The charge control agent contains a resin having a quaternary ammonium salt group as a functional group and a nigrosine dye. Even if after kneading, pulverization and classification, the toner is made spherical by melting the surfaces of the particles in a hot air current, the charge control agent is not coated and hence the charging ability thereof is not reduced.

Abstract: A receiving unit of a receiving device receives a signal arriving thereto through a transmission path as a reception signal. A delay unit outputs a delay signal obtained by delaying the reception signal by a predetermined delay time. An estimation unit estimates a transmission path characteristic. An equalizer/demodulator compensates for the delay signal with the transmission path characteristic, demodulates the compensation result, and outputs the demodulation result as a transmission signal. A replica unit compensates for the reception signal with the transmission path characteristic, demodulates the compensation result, modulates the demodulation result, and outputs the modulation result as a replica signal. The estimation unit estimates a transmission path characteristic by comparing the reception signal with the replica signal. The predetermined delay time is equal to or smaller than a time required for the processes by the replica unit and the estimation unit.

Abstract: A two-opposed-main-shaft type composite NC lathe provided with a tool changeable tool spindle and tool turrets, comprising: a left turret rest and a right turret rest provided on a lower front side of a left main shaft and a right main shaft facing each other on a Z-axis; a third tool rest positioned on an upper rear side of the left and right main shafts and provided with a tool spindle; a tool magazine holding tools therein which are to be fixed to the third tool rest; and an automatic tool changing device. The left and right main shafts are provided with main shaft motors capable of controlling a C-axis and being driven independently and synchronously with each other. The tool spindle on the third tool rest is capable of controlling the directions of the Z-axis, an X-axis, a Y-axis and a B-axis and fixing the rotations thereof.

Abstract: A communication zone is defined by a plurality of cells, which are separated from one another and has respective fixed base stations. The base stations in the first cell and the last cell are capable of bidirectional communication with a mobile station, while other base stations are capable of unidirectional communication. The base stations are connected to a zone control station, which controls communications with the mobile station within the zone.

Abstract: In a communication system, a content server reads required data from a content database and transmits the data by packet communications over public communication lines, and a network management server receives and stores the required information from the public communication lines. The network management server sends the temporarily stored data to plural transmitter stations. Each transmitter station has a corresponding dividing device. Each dividing device receives and relays to the linked transmitter station only the amount of data required for transmission to the linked transmitter station. The remaining data is simply passed by the dividing device to the next dividing device without processing the data in any way.

Abstract: A channel evaluator acquires a change predicted value from a known symbol, and a compensator compensates for a first symbol using the change predicted value. A demodulator restores a portion corresponding to this symbol with another subcarrier. A replica generator acquires a transmission replica of the restored symbol. The channel evaluator performs complex division on the replica with the symbol to acquire an amplitude phase ratio. A detector compares the amplitude phase ratio with an amplitude phase ratio acquired immediately previously. In case where an elimination condition is satisfied, the detector disregards the amplitude phase ratio acquired currently and uses an immediately previous value instead, an averaging unit averages amplitude phase ratios to acquire a next change predicted value, and the compensator compensates for a next symbol using the change predicted value. Hereinafter, the sequence of processes is repeated.

Abstract: A vehicle-vehicle communication system includes an in-vehicle wire LAN established in a vehicle. The in-vehicle wire LAN includes a plurality of devices connected by optical fiber links. A terminal for radio vehicle-vehicle communication is connected to the in-vehicle wire LAN by the optical fiber link. The terminal receives an optical digital signal in a predetermined format from the in-vehicle wire LAN. The terminal includes a light controlled oscillator and applies the received optical signal to the light controlled oscillator. The light controlled oscillator outputs a transmission signal of a frequency shifted from a predetermined frequency according to the intensity of the applied optical signal. Thus the terminal generates the transmission signal using FSK-modulation technique without converting the format of the optical signal into another format. The transmission signal is transmitted to a device in another vehicle via radio waves.