Patent application number | Description | Published |
20080200195 | Multi-Mode Control Station, Radio Communication System, Radio Station, and Radio Communication Control Method - The overall throughput of the radio communication traffic in a radio communication area in a radio communication environment where a plurality of types of radio communication systems are mixedly used in a neighboring radio communication area is improved. When a multi-mode control station ( | 08-21-2008 |
20080260069 | APPARATUS AND METHOD FOR DIGITAL WIRELESS COMMUNICATION - In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established. | 10-23-2008 |
20080299937 | Sampling Filter - The present invention aims at providing a sampling filter capable of changing a filtering characteristic without use of a complicate waveform as a control signal. A sampling filter | 12-04-2008 |
20080317148 | WIRELESS COMMUNICATIONS APPARATUS AND WIRELESS COMMUNICATION METHOD - The invention performs orthogonal frequency division multiplex processing on a transmission signal to form an OFDM modulation signal (daubed in FIG.) and performs orthogonal frequency division multiplex processing and code division multiple access processing on a transmission signal to form an OFDM-CDM modulation signal (shaded in FIG.) to transmit the OFDM modulation signal and the OFDM-CDM modulation signal, which makes it possible to transmit data in a very high rate using the OFDM modulation signal while making it possible to transmit data in a higher quality using the OFDM-CDM modulation signal than using the OFDM-modulation signal, although it is slightly inferior to OFDM modulation in terms of high rate transmission. | 12-25-2008 |
20090046818 | RECEPTION DEVICE - It is possible to demodulate a plurality of modulated signals transmitted from a plurality of antennas by using a comparatively small-size circuit with a preferable error ratio characteristic. Partial bit judgment units ( | 02-19-2009 |
20090051422 | Filter Device - Provided is a switched capacitor type filter device having a steep characteristic with a small number of taps. The filter device includes positive polarity selecting switches ( | 02-26-2009 |
20090103516 | SYNCHRONIZATION DETECTING CIRCUIT AND MULTIMODE WIRELESS COMMUNICATION APPARATUS - Multimode wireless communication apparatus supports plural wireless communication methods and includes synchronization detecting part. Digital signals output from first A/D part and second A/D part are combined by synchronization detecting part. Synchronization detecting part converts sampling frequencies of respective digital signals and performs other processes when combining digital signals. Synchronization detecting part detects synchronization timing for plural wireless communication methods by plurally performing correlation operation corresponding to respective wireless communication methods for digital signals combined, thereby providing a multimode wireless communication apparatus with its size and power consumption reduced. | 04-23-2009 |
20090103650 | METHOD FOR DIGITAL WIRELESS COMMUNICATIONS - In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established. | 04-23-2009 |
20090104880 | WIRELESS COMMUNICATION APPARATUS AND COMMUNICATION CONTROL METHOD - A wireless communication apparatus and a communication control method wherein even if there occurs a change in communication control information due to a function change, an appropriate correction is implemented to improve the communication quality. A wireless communication apparatus ( | 04-23-2009 |
20090116572 | COMMUNICATION APPARATUS AND COMMUNICATION METHOD - A communication apparatus in which only a terminal having a specific positional relationship can perform communication through a relatively simple arrangement. When initial setting is performed or communication is started, a timing calculating section ( | 05-07-2009 |
20090116594 | RADIO RECEIVER - A radio receiver including a reception processing system that uses a discrete-time frequency conversion to acquire a signal having a sampling rate corresponding to a local frequency, wherein the reception characteristic is improved when the reception processing system is applied to a system having a wide reception channel band. The radio receiver ( | 05-07-2009 |
20090135760 | MULTIMODE WIRELESS COMMUNICATION APPARATUS AND WIRELESS COMMUNICATION METHOD - A multimode wireless communication apparatus that supports plural wireless communication systems and switches wireless communication systems to communicate. The apparatus includes a signal processor capable of switching wireless communication systems by plural manners; and a controller that directs to the signal processor a combination of manners of switching wireless communication systems according to a communication environment. The signal processor switches wireless communication systems according to the combination of manners of switching wireless communication systems directed from the controller. | 05-28-2009 |
20090150470 | FAST FOURIER TRANSFORMATION CIRCUIT - Provided is a fast Fourier transformation circuit capable of optimizing an operation resource while matching a plurality of communication systems. In this circuit, an FFT circuit ( | 06-11-2009 |
20090187615 | DIGITAL FILTER - Provided is a digital filter for radio communication processing capable of dynamically modifying the characteristic and simultaneously processing a plurality of systems. In the digital filter, calculation core groups ( | 07-23-2009 |
20090257531 | SAMPLING FILTER APPARATUS AND WIRELESS COMMUNICATION APPARATUS - The present invention has an object to provide a sampling filter apparatus and a wireless communication apparatus, which are capable of changing a filter characteristic without employing complex waveforms as control signals, and also, capable of performing filtering process operations without performing a decimation, while utilizing a wide frequency space. A sampling filter apparatus | 10-15-2009 |
20090270061 | SAMPLING MIXER AND RECEIVER - It is an object of the present invention to provide a sampling mixer and a receiver, capable of optimizing a sampling rate of an output signal in response to a fractional band of a modulation band with respect to an RF frequency of the received signal. A sampling mixer of the present invention, includes a history capacitor | 10-29-2009 |
20090285329 | TRANSMISSION POWER CONTROL METHOD AND TRANSMISSION APPARATUS - Even when there is limit placed upon transmission power control time, the transmission power control method enables accurate control transmission power. The transmission power control method includes: a first measuring step of measuring, in a symbol interval before a symbol interval where mode of the power amplifier changes, output power of the power amplifier before mode changes; a first setting step of setting target power of the power amplifier after mode changes based on a measurement result obtained in the first measuring step and a transmission power control signal; a second measuring step of measuring, in the symbol interval where mode of the power amplifier changes, output power of the power amplifier after mode changes, the output power being controlled using the target power set in the first setting step; and a second step of setting corrected target power based on a measurement result obtained in the second measuring step. | 11-19-2009 |
20100029224 | POLAR MODULATION TRANSMISSION APPARATUS - By compensating for a detection result of the detector in feedback control of output power of the power amplifier, the polar modulation transmission apparatus is able to realize accurate transmission power control. Polar modulation transmission apparatus | 02-04-2010 |
20100029225 | POLAR MODULATION TRANSMISSION APPARATUS - By compensating for a detection result of the detector in feedback control of output power of the power amplifier, the polar modulation transmission apparatus is able to realize accurate transmission power control. Polar modulation transmission apparatus | 02-04-2010 |
20100066429 | POWER SUPPLY VOLTAGE FORMING DEVICE AND POLAR MODULATION TRANSMISSION DEVICE - Provided is a power voltage forming device which can correct an offset voltage of a high-frequency power amplifier without degrading distortion characteristic of a high-frequency power amplifier. The power voltage forming device ( | 03-18-2010 |
20100098016 | WIRELESS COMMUNICATIONS APPARATUS AND WIRELESS COMMUNICATION METHOD - A communication method of a base station transmits a modulation signal based on an OFDM (orthogonal frequency division multiplexing) scheme to a plurality of communication terminals. The method includes using a transmission frame on which a first subcarrier group and a second subcarrier group are arranged, the first subcarrier group on which a signal using a first transmission scheme is arranged, and the second subcarrier group on which a signal using a second transmission scheme different from the signal using the first transmission scheme in transmission quality is arranged. The method also includes determining, on a per frame basis, which subcarrier group is allocated to each of the plurality of communication terminals and how many subcarriers are allocated to said each of the plurality of communication terminals, and forming the transmission frame based on the determined information. The method further includes transmitting the modulation signal using the transmission frame. | 04-22-2010 |
20100128815 | Receiving Apparatus and Transmitting Apparatus - A partial bit demodulation section that demodulates partial bits among a plurality of bits that form 1 symbol of each modulated signal using a detection method different from likelihood detection, signal point reduction sections that reduce the number of candidate signal points using demodulated partial bits, and a likelihood detection section obtains received digital signals by performing likelihood detection based on the Euclidian distances between the reduced candidate signal points and a reception point, are provided. By this, only some bits which are unlikely to be erroneous are found by the partial bit demodulation section, and other bits can be found by the likelihood detection section, enabling bit error rate performances to be effectively improved with a comparatively small computational complexity. | 05-27-2010 |
20100172444 | METHOD FOR DIGITAL WIRELESS COMMUNICATIONS - In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established. | 07-08-2010 |
20100202562 | TRANSMISSION DEVICE, RECEPTION DEVICE AND RADIO COMMUNICATION METHOD - A transmitting apparatus includes a first OFDM modulator that generates a first OFDM modulation signal by modulating a first information signal using a first modulation scheme, the first OFDM modulation signal having a plurality of subcarriers. A second OFDM modulator generates a second OFDM modulation signal by modulating a second information signal using the first modulation scheme, the second OFDM modulation signal having a plurality of subcarriers, and that generates a third OFDM modulation signal by changing a second position in an in-phase quadrature-phase plane in which a signal point of the second OFDM modulation signal is positioned, to a third position, the third position being different from a first position in the in-phase quadrature-phase plane in which a signal point of the first OFDM modulation signal is positioned. A multiplexer generates a multiplexed signal to be transmitted in a common frequency band, by multiplexing the first OFDM modulation signal and the third modulation signal. A transmitter transmits the multiplexed signal. | 08-12-2010 |
20100215119 | RECEPTION APPARATUS - A reception apparatus includes a plurality of antennas for receiving modulation signals of channels in the same frequency band, an received signal strength intensity estimation unit for estimating the reception received signal strength intensity of each reception signal, transmission path fluctuation estimation units for estimating a transmission path fluctuation of each channel of the reception signal, phase difference estimation units for calculating a phase difference of the transmission path fluctuation estimation signal of a predetermined channel of each antenna and outputting it as a phase difference signal, and a signal selection unit for selecting and outputting a reception quadrate baseband signal for isolating a signal of each channel from the reception signals and a transmission path fluctuation estimation signal of each channel. Thus, by isolating and demodulating a plurality of multiplexed modulated signals received, it is possible to improve the data transmission rate. | 08-26-2010 |
20100291885 | MULTIMODE-COMPAIBLE POLAR MODULATION TRANSMISSION DEVICE AND MULTIMODE RADIO COMMUNICATION METHOD - An object of the invention is to provide a multimode polar modulation device and a multimode radio communication method for making it possible to decrease the distortion compensation processing data capacity while maintaining the distortion compensation accuracy and also making it possible to efficiently store the distortion compensation processing data corresponding to a multimode modulation signal adaptively acquired in memory. | 11-18-2010 |
20110002421 | RECEPTION DEVICE - It is possible to demodulate a plurality of modulated signals transmitted from a plurality of antennas by using a comparatively small-size circuit with a preferable error ratio characteristic. Partial bit judgment units ( | 01-06-2011 |
20110044412 | MULTI-ANTENNA RECEPTION APPARATUS, MULTI-ANTENNA RECEPTION METHOD, MULTI-ANTENNA TRANSMISSION APPARATUS AND MULTI-ANTENNA COMMUNICATION SYSTEM - Soft decision sections ( | 02-24-2011 |
20110085590 | METHOD FOR DIGITAL WIRELESS COMMUNICATIONS - In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established. | 04-14-2011 |
20110158350 | RECEIVING APPARATUS AND TRANSMITTING APPARATUS - A partial bit demodulation section that demodulates partial bits among a plurality of bits that form 1 symbol of each modulated signal using a detection method different from likelihood detection, signal point reduction sections that reduce the number of candidate signal points using demodulated partial bits, and a likelihood detection section that obtains received digital signals by performing likelihood detection based on the Euclidian distances between the reduced candidate signal points and a reception point, are provided. By this means, only some bits which are unlikely to be erroneous are found by the partial bit demodulation section, and other bits can be found by the likelihood detection section, enabling bit error rate performances to be effectively improved with a comparatively small computational complexity. | 06-30-2011 |
20110211475 | WIRELESS COMMUNICATIONS APPARATUS AND WIRELESS COMMUNICATIONS METHOD - A wireless communication method of a base station that transmits a modulation signal based on an orthogonal frequency division multiplexing scheme to a plurality of terminals. The method includes determining, for each terminal of the plurality of terminals, which subcarrier group or how many symbols along a time axis are to be allocated in a transmission frame, the transmission frame including a first period in which first transmission symbols are arranged and a second period in which second transmission symbols which are different from the first transmission symbols are arranged. The method also includes forming the transmission frame according to a determined allocation, wherein a plurality of symbols on a frequency axis for transmitting N bits (N is a natural number) are arranged within a part of the first period, by using a modulation scheme whereby N bits can be transmitted using one symbol. The method further includes transmitting the modulation signal using the transmission frame. | 09-01-2011 |
20110235752 | COMMUNICATION METHOD AND RADIO COMMUNICATION APPARATUS - A radio communication apparatus for transmitting and receiving modulation signals of a plurality of channels in the same frequency band via a plurality of antennas. A communication method is based on information on electric wave propagation environment corresponding to each antenna of the communication partner and transmission is performed by selecting a transmission method for transmitting modulation signals of channels in the same frequency band from a plurality of antennas or a transmission method for transmitting a modulation signal of one channel from one antenna. Thus, it is possible to multiplex a plurality of modulation signals so as to be transmitted and to demultiplex and demodulate the transmitted multiplexed modulation signals at a reception unit, thereby improving the data transmission rate. | 09-29-2011 |
20110291755 | TRANSMISSION POWER CONTROL METHOD AND TRANSMISSION POWER CONTROL APPARATUS - When switching the mode of a power amplifier between compressed mode and uncompressed mode, accurate transmission power control is realized. A transmission power control method includes setting a power setting value of mode to switch to, such that an inter-mode output power error is canceled (equal to step ST | 12-01-2011 |
20110305171 | TRANSMISSION CIRCUIT AND TRANSMISSION METHOD - A transmission circuit that performs modulation based on a phase difference signal and an amplitude signal includes an asymmetrical phase rotation device. The asymmetrical phase rotation device performs an operation of subtracting 2π from a value of the phase difference signal when the value of the phase difference signal is greater than a predetermined positive threshold value, or an operation of adding 2π to the value of the phase difference signal when the value of the phase difference signal is less than a predetermined negative threshold value. Accordingly, the transmission circuit has distortion reduction characteristics improved uniformly over a range of frequencies higher or lower than a carrier wave band. | 12-15-2011 |
20120001688 | TRANSMISSION POWER CONTROL METHOD AND TRANSMISSION POWER CONTROL APPARATUS - When switching the mode of a power amplifier between a compressed mode and an uncompressed mode, an accurate transmission power control is realized. A transmission power control method includes calculating an intra-mode output power error from a power setting value in a mode before switching as a comparison standard value error (equal to step ST | 01-05-2012 |
20120076051 | WIRELESS TERMINAL AND COMMUNICATION SYSTEM SWITCHING METHOD - A wireless terminal involving small redundancy that can be reconfigured to a configuration compatible with a plurality of systems using the hardware resources compatible with one system is provided. A wireless terminal | 03-29-2012 |
20120082268 | METHOD FOR DIGITAL WIRELESS COMMUNICATIONS - In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established. | 04-05-2012 |
20120147989 | INTERLEAVER, INTERLEAVING METHOD, TRANSMISSION APPARATUS, AND TRANSMITTING METHOD - Soft decision sections provisionally decide each modulated signal separated using an inverse matrix calculation of a channel fluctuation matrix at separation section. Signal point reduction sections reduce candidate signal points of a multiplexed modulated signal using the provisional decision results. Soft decision sections make a correct decision using the reduced candidate signal points and obtain received data of each modulated signal. This allows received data RA, RB with a good error rate characteristic to be obtained with a relatively small number of calculations without reducing data transmission efficiency. | 06-14-2012 |
20120183101 | TRANSMISSION METHOD, TRANSMISSION APPARATUS, AND RECEPTION APPARATUS - A transmission method for transmitting modulation signals of a plurality of channels to the same frequency band from a plurality of antennas. At the time when a symbol used for demodulation is inserted in a channel, in another channel symbol, the same phase and quadrature signals in the in-phase-quadrature plane are made to be zero signals. Thus, a plurality of modulation signals are multiplexed and transmitted and the transmitted multiplexed modulation signals are demultiplexed and demodulated at a reception apparatus, thereby improving the data transmission rate. | 07-19-2012 |
20120257688 | TRANSMISSION AND RECEPTION APPARATUS AND METHOD - A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included in the reception signals. | 10-11-2012 |
20120314803 | TRANSMITTING APPARATUS, TRANSMISSION METHOD, RECEIVING APPARATUS, AND RECEIVING METHOD - A transmitting apparatus and method transmits different modulated signals from a plurality of antennas, and employs a configuration that includes a modulation section that obtains a modulated signal by performing signal point mapping of transmit bits using a signal point arrangement that is divided into a plurality of signal point sets on the IQ plane, whereby the minimum distance between signal points within a signal point set is smaller than the minimum signal point distance between signal point sets; and an antenna that transmits a modulated signal obtained by the modulation section. A signal point generating apparatus generates a first and second symbols to be transmitted by first and second antennas, respectively. | 12-13-2012 |
20120328047 | TRANSMISSION DEVICE, RECEPTION DEVICE, AND RADIO COMMUNICATION METHOD - A transmitting apparatus includes an OFDM modulator that generates a first modulation symbol by modulating a first information signal using a first modulation scheme, a signal point of the first modulated information signal being at a first position in an in-phase quadrature-phase plane. A second modulation symbol by modulating a second information signal using the first modulation scheme, and by changing a second position at which a signal point of the modulated second information signal is arranged to a third position in the in-phase quadrature-phase plane, and an OFDM modulation signal including the first modulation symbol and the second modulation symbol, wherein the OFDM modulation signal comprises a plurality of subcarriers. | 12-27-2012 |
20130003887 | TRANSMISSION APPARATUS, RECEPTION APPARATUS AND DIGITAL RADIO COMMUNICATION METHOD - A transmission method includes generating first symbols for transmitting data, a signal point of each of the first symbols on an in-phase and quadrature-phase plane comprising an in-phase component and a quadrature-phase component and generating a second symbol, the second symbol being a pilot symbol. The method further includes selecting an insertion pattern of the second symbol, from a plurality of predetermined insertion patterns, inserting the second symbol in the first symbols based on the selected insertion pattern to generate a transmission signal, and transmitting the transmission signal. The first symbols are generated using a modulation scheme selected from a plurality of modulation schemes. | 01-03-2013 |
20130155989 | TRANSMISSION METHOD - A transmission method includes generating a plurality of orthogonal frequency division multiplexing (OFDM) signals, each signal including different data and some of the plurality of OFDM signals including pilot symbols. The pilot symbols are assigned to a predetermined subcarrier in predetermined time. At least one of the plurality of OFDM signals is assigned the pilot symbols to the predetermined subcarrier in the predetermined time, and other OFDM signals are assigned data to the predetermined subcarrier in the predetermined time. The method further includes converting each of the plurality of OFDM signals to a radio signal and transmitting each of the radio signals from a different antenna. | 06-20-2013 |
20130170577 | MULTIMODE TRANSMITTER APPARATUS - Provided is a multimode transmitter apparatus that, in a case of using different paths to process modulated signals, can suppress the signal overlapping or loss that would occur during a path switching. In the apparatus, a baseband modulating unit ( | 07-04-2013 |
20130176965 | WIRELESS COMMUNICATION METHOD AND TRANSMISSION APPARATUS - A wireless communication method for a transmission apparatus that transmits an OFDM (orthogonal frequency division multiplexing) signal using a communication band, which comprises a plurality of subcarrier groups each including a plurality of subcarriers. The method includes specifying which subcarrier group and how many subcarriers are to be used to transmit the OFDM signal, determining a configuration of a transmission frame, generating the OFDM signal by mapping data symbols according to the determined configuration of the transmission frame, and transmitting the generated OFDM signal. | 07-11-2013 |
20130223265 | COMMUNICATION PROCESSOR AND COMMUNICATION PROCESSING METHOD - The present invention provides a communication processor that is compatible with a plurality of communication protocols and also limits increases in circuit scale. A communication processor ( | 08-29-2013 |
20130223371 | RECEIVING APPARATUS AND RECEIVING METHOD - A multiple-input and multiple-output (MIMO) transmission apparatus includes a modulation signal generating section and a MIMO transmitting section. The modulation signal generating section generates: (i) a first OFDM modulation signal, in which a plurality of subcarriers include a subcarrier carrying a pilot symbol and a subcarrier carrying a data symbol, in both a first time period and a second time period; and (ii) a second OFDM modulation signal, in which the plurality of subcarriers include a subcarrier carrying a pilot symbol and a subcarrier carrying a data symbol in the first time period, while in the second time period an in-phase component and a quadrature-phase component of every subcarrier included in the plurality of subcarriers are zero. The MIMO transmitting section transmits the first OFDM modulation signal from a first antenna and transmits the second OFDM modulation signal from a second antenna. | 08-29-2013 |
20130223567 | TRANSMISSION AND RECEPTION APPARATUS AND METHOD - A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included in the reception signals. | 08-29-2013 |
20130251004 | TRANSMISSION DEVICE, RECEPTION DEVICE, AND RADIO COMMUNICATION METHOD - A transmitting apparatus includes an OFDM modulator that generates a first modulation symbol by modulating a first information signal using a first modulation scheme, a signal point of the first modulated information signal being at a first position in an in-phase quadrature-phase plane. A second modulation symbol by modulating a second information signal using the first modulation scheme, and by changing a second position at which a signal point of the modulated second information signal is arranged to a third position in the in-phase quadrature-phase plane, and an OFDM modulation signal including the first modulation symbol and the second modulation symbol, wherein the OFDM modulation signal comprises a plurality of subcarriers. | 09-26-2013 |
20130251008 | METHOD FOR DIGITAL WIRELESS COMMUNICATIONS - In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established. | 09-26-2013 |
20130315343 | TRANSMITTING APPARATUS, RECEIVING APPARATUS, TRANSMISSION METHOD, AND RECEPTION METHOD - In a communication system in which propagation path error tolerance is improved by switching the modulation method or error correction method adaptively according to the state of the propagation path, signals MX, MY, CX, and CY indicating the modulation method and error correction method used by the transmitting side are transmitted arranged at discrete locations within the same frame. By this means, the possibility of discretely arranged signals MX and MY, or CX and CY, both degrading is made low even if the transmit signal experiences fading or propagation path fluctuations. As a result, it is possible for the modulation method information signal and/or error correction method information signal to be restored correctly on the receiving side. | 11-28-2013 |
20130322564 | TRANSMISSION METHOD AND TRANSMISSION APPARATUS - Of any one of a transmission method X of transmitting modulated signal A and modulated signal B including the same data from a plurality of antennas and a transmission method Y of transmitting modulated signal A and modulated signal B having different data from the plurality of antennas, a base station apparatus does not change the transmission method during data transmission and changes only the modulation scheme. The base station apparatus transmits modulated signal A and modulated signal B to a communication terminal apparatus using the determined transmission method and modulation scheme. In this way, it is possible to improve data transmission efficiency when transmitting data using the plurality of antennas. | 12-05-2013 |
20130329836 | TRANSMITTING APPARATUS, TRANSMITTING METHOD, RECEIVING APPARATUS AND RECEIVING METHOD - Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S2(i) and S2(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S1(i) and S1(i)′ obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances. | 12-12-2013 |
20140010331 | TRANSMISSION METHOD, TRANSMISSION APPARATUS AND RECEPTION APPARATUS - A method of generating modulation signals is disclosed including generally three steps. A plurality of modulation signals are generated, each of which is to be transmitted from a different one of a plurality of antennas in an identical frequency band, wherein each modulation signal includes a pilot symbol sequence including a plurality of pilot symbols used for demodulation. Each of the pilot symbol sequences is inserted at the same temporal point in each modulation signal, wherein the pilot symbol sequences are orthogonal to each other with zero mutual correlation among the plurality of modulation signals, each pilot symbol having a non-zero amplitude, the quantity of the plurality of pilot symbols in each sequence being greater than the quantity of the plurality of modulation signals to be transmitted. The plurality of modulation signals each including different transmission data and one of the pilot symbol sequences are output to the antennas. | 01-09-2014 |
20140086366 | RECEIVING APPARATUS AND RECEIVING METHOD - A transmitting apparatus and method transmits different modulated signals from a plurality of antennas, and employs a configuration that includes a modulation section that obtains a modulated signal by performing signal point mapping of transmit bits using a signal point arrangement that is divided into a plurality of signal point sets on the IQ plane, whereby the minimum distance between signal points within a signal point set is smaller than the minimum signal point distance between signal point sets; and an antenna that transmits a modulated signal obtained by the modulation section. A signal point generating apparatus generates a first and second symbols to be transmitted by first and second antennas, respectively. | 03-27-2014 |
20140126412 | WIRELESS COMMUNICATION APPARATUS AND WIRELESS COMMUNICATION METHOD - A communication method of a base station transmits a modulation signal based on an OFDM (orthogonal frequency division multiplexing) modulation scheme to a plurality of communication terminals. The method includes forming a transmission frame on which a first subcarrier group and a second subcarrier group are arranged, and determining on a per frame basis, which subcarrier group of the first subcarrier group and the second subcarrier group is allocated to each of the plurality of communication terminals and what number of subcarriers are selected from the subcarrier group that is allocated to each of the plurality of communication terminals. The method further includes forming the transmission frame based on the determined subcarrier group and the determined number of subcarriers, transmitting the modulation signal including the transmission frame, and receiving feedback information including radio propagation condition estimation information from each of the plurality of communication terminals. | 05-08-2014 |
20140177619 | TRANSMISSION AND RECEPTION APPARATUS AND METHOD - A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included in the reception signals. | 06-26-2014 |
20140192855 | ADAPTIVE EQUALIZER - An adaptive equalizer capable of suppressing an increase in circuit scale and an increase in operation clock frequency. An adaptive equalizer ( | 07-10-2014 |
20140192856 | ADAPTIVE EQUALIZER - An adaptive equalizer ( | 07-10-2014 |
20140247899 | TRANSMISSION SIGNAL GENERATOR, TRANSMISSION SIGNAL GENERATING METHOD, RECEPTION SIGNAL GENERATOR, AND RECEPTION SIGNAL GENERATING METHOD - Modulated signal A is transmitted from a first antenna, and modulated signal B is transmitted from a second antenna. As modulated signal B, modulated symbols S2(i) and S2(i+1) obtained from different data are transmitted at time i and time i+1 respectively. In contrast, as modulated signal A, modulated symbols S1(i) and S1(i)′ obtained by changing the signal point arrangement of the same data are transmitted at time i and time i+1 respectively. As a result the reception quality can be changed intentionally at time i and time i+1, and therefore using the demodulation result of modulated signal A of a time when the reception quality is good enables both modulated signals A and B to be demodulated with good error rate performances. | 09-04-2014 |
20140254721 | TRANSMISSION APPARATUS, RECEPTION APPARATUS AND DIGITAL RADIO COMMUNICATION METHOD - A transmission method includes modulating a transmission signal using a modulation scheme selected from a plurality of modulation schemes, to generate a first symbol sequence and generating at least one second symbol including a pilot symbol generated using a PSK modulation scheme. The method includes changing an insertion interval of the second symbol to be inserted in the first symbol sequence, to generate a modulation signal and transmitting the modulation signal. The second symbol is configured for synchronization in a reception apparatus. | 09-11-2014 |
20140307828 | TRANSMISSION SIGNAL GENERATION METHOD, TRANSMISSION SIGNAL GENERATION APPARATUS, RECEPTION SIGNAL GENERATION METHOD, AND RECEPTION SIGNAL GENERATION APPARATUS - Of any one of a transmission method X of transmitting modulated signal A and modulated signal B including the same data from a plurality of antennas and a transmission method Y of transmitting modulated signal A and modulated signal B having different data from the plurality of antennas, a base station apparatus does not change the transmission method during data transmission and changes only the modulation scheme. The base station apparatus transmits modulated signal A and modulated signal B to a communication terminal apparatus using the determined transmission method and modulation scheme. In this way, it is possible to improve data transmission efficiency when transmitting data using the plurality of antennas. | 10-16-2014 |
20150058703 | TRANSMITTING APPARATUS, RECEIVING APPARATUS, TRANSMISSION METHOD, AND RECEPTION METHOD - A transmission frame generating device includes a control information signal generator and a frame former. The control information signal generator generates a modulation method information signal indicating a modulation method of a data signal and an error correction method information signal indicating an error correction method of the data signal. The frame former forms the transmission frame by repeating and discretely arranging the same modulation method information signal on a first multiple of a plurality of subcarriers on a frequency axis and by repeating and discretely arranging the same error correction method information signal on a second multiple of the plurality of the subcarriers on the frequency axis. | 02-26-2015 |
20150063271 | RECEIVING APPARATUS AND RECEIVING METHOD - A receiver receives, using a plurality of antennas, a multiplexed signal that includes (i) a first OFDM modulation signal with a subcarrier carrying a symbol including multiplex information and a subcarrier carrying a pilot symbol and a subcarrier carrying a data symbol and (ii) a second OFDM modulation signal with a subcarrier carrying a symbol including multiplex information and a subcarrier carrying the pilot symbol and a subcarrier carrying the data symbol. A decoder uses the symbol including multiplex information and decodes the data symbol. | 03-05-2015 |