Abstract: A radio client device scans a channel allocated to a predetermined repeater, and transmits a request for location registration to the predetermined repeater in a case of detecting a usage condition signal. A repeater, in a case of receiving a request for location registration from a radio client device, conducts location registration for the radio client device, transmits information about the radio client device whose location is registered to a predetermined repeater in a communication area of the repeater or to a predetermined repeater in a different communication area, and in a case of receiving information about a radio client device whose location is registered from another repeater in the communication area of the repeater, transmits information about the radio client device whose location is registered to the predetermined repeater in the different communication area.

Abstract: An identification provider provides predetermined identification data to an input signal, and generates a first signal. A differential encoder performs a differential encoding of a data series that is an aggregate of data having a matching number of elements to that contained in the first signal, and generates a second signal. A modulator modulates each of the first and second signals using a primary modulation, and generates first and second modulated data. An IFFT calculator performs an inverse fast Fourier transformation on each of the first and second modulated data, and generates first and second inverse transformed data. A selector compares peak-to-average power ratios calculated by baseband signals associated with the first and second inverse transformed data, and selects a baseband signal having the lower peak-to-average power ratio. A transmitter generates a transmission signal based on the selected baseband signal, and transmits the transmission signal.

Abstract: A relaying device includes a wireless apparatus interface, a signal processing unit connected to the wireless apparatus interface, a network interface, and a packet processing unit connected to the network interface. The relaying device is provided with multiple communication paths including the wireless apparatus interface, the signal processing unit, and the packet processing unit, and each communication path has a mixing unit configured to additively synthesize an uplink audio signal and a downlink audio signal of other communication path to the uplink audio signal and input the synthesized signal to the packet processing unit, and configured to additively synthesize an uplink audio signal and a downlink audio signal of other communication path to the downlink audio signal and input the synthesized signal to the signal processing unit.

Abstract: The electronic apparatus includes a submergence detector for detecting submergence of the electronic apparatus in the water and retrieval thereof, a light-emitting device provided within an enclosure of the electronic apparatus, an illumination circuit for lighting the light-emitting device when an illumination signal is input, a controller for causing the light-emitting device to blink by generating the illumination signal at prescribed blinking intervals at least during a period from a point of submergence to a point of retrieval of the electronic apparatus and inputting the illumination signal to the illumination circuit, and a power control circuit for activating the controller by supplying electric power thereto if the electric power is not supplied to the controller when the submergence detector detects submergence.

Abstract: A modulator generates a modulation signal from an input signal. A serial-parallel converter generates a subcarrier modulation signal from the modulation signal. An inserter inserts a transmission-side data series, generated by multiplying a data series having an autocorrelation property by a predetermined series amplitude coefficient, in a signal for synthesis, generated by multiplying the subcarrier modulation signal by a predetermined signal amplitude coefficient, in such a way that elements in the signal for synthesis and elements in the transmission-side data series are alternately positioned, thereby generating first data. An IFFT unit performs an inverse fast Fourier transformation on the first data. A separator generates a baseband signal based on first half data of an operation result from the IFFT unit. A transmitter generates a transmission signal from the baseband signal, and transmits it to another apparatus via an antenna.

Abstract: A modulator generates a modulation signal from an input signal. A serial-parallel converter generates a subcarrier modulation signal from the modulation signal. An IFFT unit performs an inverse fast Fourier transformation on the subcarrier modulation signal, generating first data. A decomposer decomposes the first data into real data and imaginary data. An operator performs a predetermined operation using a predetermined threshold value, a boundary value and the real data, generating positive data and negative data. Another operator performs a similar operation on the imaginary data. A generator adds the positive data and negative data based on the real data, and adds the positive data and negative data based on the imaginary data, generating real operation data and imaginary operation data. A synthesizer synthesizes both operation data to generate a baseband signal. A transmitter generates a transmission signal from the baseband signal, and transmits it to another apparatus via an antenna.

Abstract: A modulator subjects an input signal to primary modulation to generate a primary modulated signal. A transmitter generates and transmits a transmission signal based on a secondary modulated signal generated from the primary modulated signal. A retransmission request receiver receives a retransmission request that contains identification information. An operator uses a data sequence that is a set of elements of a same number as a number of elements in an input signal identified by the identification information and with element values of 1 or 0 to generate operation data whose elements are values of exclusive OR of respective elements of the input signal and respective elements of the data sequence that are at same positions as positions of the respective elements of the input signal. If a retransmission request receiver receives a retransmission request, the modulator and transmitter perform the above processing using the operation data as an input signal.

Abstract: A modulator generates modulation signals from input signals. A combiner arranges subcarrier modulation signals based on the modulation signals in order thereby to generate a compound matrix. The shifter shifts elements of each row of the compound matrix to generate shift matrix. An IFFT calculator subjects the shift matrix to inverse fast Fourier transformation to generate inverse transformation matrix. A maximum detector detects a column with a highest peak-to-average power ratio among columns of the inverse transformation matrix. A minimum detector detects an inverse transformation matrix including a column with a lowest peak-to-average power ratio among columns of inverse transformation matrices detected by the maximum detector. A transmitter generates a transmission signal based on baseband signals generated from each column of the inverse transformation matrix detected by the minimum detector, and transmits the transmission signal.

Abstract: A modulator generates a modulation signal from an input signal, and a serial-parallel converter generates a subcarrier modulation signal from the modulation signal. An IFFT unit performs an inverse fast Fourier transformation on the subcarrier modulation signal to generate first data. An operator multiplies respective elements of the first data by amplitude coefficients, and further adds dispersion coefficients to the multiplication result, the amplitude coefficients being real numbers other than 0 defined for the respective elements, at least one of the amplitude coefficients having a value other than 1, the dispersion coefficients being complex numbers defined for the respective components, and at least one of the dispersion coefficients having a value other than 0. Then, data symbols are generated based on a calculation result. A transmitter transmits a transmission frame including the data symbols to another apparatus via an antenna.

Abstract: A modulator generates a modulation signal from an input signal, and a serial-parallel converter generates a subcarrier modulation signal from the modulation signal. An IFFT unit performs an inverse fast Fourier transformation on the subcarrier modulation signal, and a decomposer decomposes a calculation result into a real part data and an imaginary part data. A calculator applies a predetermined calculation with respect to each element the value of which is equal to or greater than a positive threshold value and each element the value of which is equal to or less than a negative threshold value among the real part data and the imaginary part data. A synthesizer synthesizes the real part data and the imaginary part data to generate a baseband signal, and a transmitter generates a transmission signal from the baseband signal, and transmits it to another apparatus via an antenna.

Abstract: A series generator divides a data series having an autocorrelation property equally into a certain number to generate subdata series. A modulator multiplies a predetermined amplitude coefficient and a unique number by each element of the subdata series, respectively, and rearranges the subdata series and synthesizes the rearranged subdata series to generate the modulation data. An IFFT unit performs an IFFT on the modulation data. The calculator divides the calculation result equally into the certain number to generate the sub calculation results, and multiplies an equalization coefficient by each element of the sub calculation results. A synthesizer generates a baseband signal by arranging the sub calculation results, so that an arranged position corresponds to a position at the time of being divided equally, and synthesizing the arranged result. A transmitter generates the transmission signal and transmits it to another apparatus via an antenna.

Abstract: A modulator performs a predetermined operation for making an absolute value of an operation result of at least one element of an input signal greater than 0 on the individual elements of the input signal. The modulator generates post-operation data by associating individual elements of the input signal with individual elements of a data series which is a set of pieces of data which are equal in number to the elements of the input signal and whose absolute values are equal to one another, and multiplying the individual elements of the input signal which are subjected to the predetermined operation by the elements of the data series. An IFFT calculator performs inverse fast Fourier transformation on the post-operation data, and a synthesizer synthesizes operation results from the IFFT calculator to generate a baseband signal. A transmitter generates a transmission signal from the baseband signal and transmits the transmission signal.

Abstract: A modulator generates a subcarrier modulation signal from an input signal, a parallel-serial converter generates a subcarrier modulation signal from the modulation signal. An IFFT calculator performs reverse Fast Fourier Transform on the subcarrier modulation signal, and a separator separates a calculation result into real part data and imaginary part data. A real part calculator performs a calculation on each element of the real part data to generate real part post-distribution data. An imaginary part calculator performs the data processing on the imaginary part data in the same manner, and generates imaginary part post-distribution data. A combiner combines the real part post-distribution data and the imaginary part post-distribution data to generate a baseband signal, and a transmitter which generates a transmission signal from the baseband signal to transmit generated transmission signal.

Abstract: The modulator creates modulated signals from input signals. The series/parallel converter creates subcarrier modulated signals from the remaining data and modulated signals. The arithmetic operator arranges and combines a first number of elements of the subcarrier modulated signals from the first one and a second number of elements of a data series from the first one each multiplied by a given amplitude coefficient to create arithmetic operation data. The IFFT executor executes the inverse fast Fourier transformation of the arithmetic operation data. The combiner creates baseband signals from the arithmetic operation results. The determiner calculates the peal-to-average power ratio of the baseband signals. The processing of the arithmetic operator to the determiner is repeated while changing at least one of given numbers until the baseband signals complying with a given criterion are detected.

Abstract: A first calculator generates first computational data by reordering elements in at least one of either a real data sequence or an imaginary data sequence constituting a data sequence having a number of elements determined according to a number of elements in a preamble model. A second calculator generates second computational data in which elements of data obtained by applying a fast Fourier transform to the first computational data are spaced apart by a designated number of elements. A preamble generator generates a preamble by multiplying each element of the second computational data by an element of the preamble model at a same position as the each element. A preamble determiner determines on the preamble as a preamble of the transmit signal in a case in which a peak-to-average power ratio of data obtained by applying an inverse fast Fourier transform to the preamble matches a predetermined criterion.

Abstract: When a changer changes a communication parameter based on a channel characteristic, a selector selects a switch data sequence corresponding to the changed communication parameter. A serial-parallel converter performs a serial-parallel conversion on a switch data sequence. An IFFT unit performs an IFFT. A transmitter synthesizes a calculation result from the IFFT unit to generate data symbol, and generates a transmission frame based on the data symbol. The transmitter then transmits the transmission frame to a second apparatus. A receiver receives a transmission frame from the second apparatus to generate data symbol. An FFT unit performs an FFT on the data symbol to generate a parallel signal. If a correlator determines that a notification of the change in the communication parameter has been correctly transmitted based on an autocorrelation analysis of the parallel signal, a communication apparatus starts communication using the changed communication parameter.

Abstract: A first calculator generates first computational data by multiplying each element in a result obtained by applying a fast Fourier transform to data containing at least one of a real data sequence and an imaginary data sequence with reordered elements by an element of a preamble model at a same position as the each element. A second calculator generates second computational data by performing computation that converts an absolute value of each element in the inverse fast Fourier-transformed first computational data into a value in a predetermined range. A third calculator generates third computational data by multiplying each element in the fast Fourier-transformed second computational data by an element of the preamble model at a same position as the each element. A decider generates the third computational data as a preamble in a case of the PAPR of the inverse fast Fourier-transformed third computational data matching a predetermined criterion.

Abstract: A first calculator generates first computational data by multiplying each element in a result obtained by applying a fast Fourier transform to data containing at least one of a real data sequence and an imaginary data sequence with reordered elements by an element of a preamble model at a same position as the each element. A second calculator generates second computational data by performing computation that converts an absolute value of each element in the inverse fast Fourier-transformed first computational data into a value in a predetermined range. A third calculator generates third computational data by multiplying each element in the fast Fourier-transformed second computational data by an element of the preamble model at a same position as the each element. A decider generates the third computational data as a preamble in a case of the PAPR of the inverse fast Fourier-transformed third computational data matching a predetermined criterion.

Abstract: A wireless communication apparatus is provided for selecting an optimum frequency even when radio wave conditions have changed. A wireless communication apparatus provided with a frequency selector for selecting an optimum frequency for establishing a link for mutually transmitting and receiving has a transceiver for transmitting radio waves to another wireless communication apparatus and receiving from the other wireless communication apparatus radio waves responding to those transmitted radio waves, a quality analyzer for analyzing communication quality indicating the condition of the link from the received radio waves, and a quality updater for updating the analyzed communication quality on the basis of time elapsed from when the radio waves were received. In addition, the frequency selector selects the optimum frequency on the basis of the updated communication quality.

Abstract: A radio client device scans a channel allocated to a predetermined repeater, and transmits a request for location registration to the predetermined repeater in a case of detecting a usage condition signal. A repeater, in a case of receiving a request for location registration from a radio client device, conducts location registration for the radio client device, transmits information about the radio client device whose location is registered to a predetermined repeater in a communication area of the repeater or to a predetermined repeater in a different communication area, and in a case of receiving information about a radio client device whose location is registered from another repeater in the communication area of the repeater, transmits information about the radio client device whose location is registered to the predetermined repeater in the different communication area.