Patent application number | Description | Published |
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 |
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 |
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 |
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 |
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 |
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 |
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 |
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 |
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 |
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 |
Patent application number | Description | Published |
20100266059 | RADIO COMMUNICATION APPARATUS CAPABLE OF SWITCHING MODULATION SCHEMES - A radio communication apparatus that is capable of switching modulation schemes. The radio communication apparatus includes a QPSK modulation signal generator, a QAM modulation signal generator, a transmission radio, and a common transmission power amplifier. The QPSK modulation signal generator modulates transmission data by a QPSK modulation scheme and outputs a QPSK modulation signal. The QAM modulation signal generator modulates transmission data by a QAM scheme and outputs a QAM modulation signal. The transmission radio receives the QPSK modulation signal or the QAM modulation signal and outputs a transmission signal, which is amplified by the common transmission power amplifier. The QPSK modulation signal generator and the QAM modulation signal generator each output signal component that make an average transmission power of the QAM modulation signal in the common transmission power amplifier smaller than an average transmission power of the QPSK modulation signal in the common transmission power amplifier. | 10-21-2010 |
20110200086 | RADIO COMMUNICATION APPARATUS CAPABLE OF SWITCHING MODULATION SCHEMES - A transmitting apparatus includes a modulation signal generating section that generates a modulation signal by modulating transmission data using one of a plurality of modulation schemes. The plurality of modulation schemes include a first modulation scheme, a second modulation scheme, and a third modulation scheme, where the first modulation scheme has maximum m-ary modulation value, the second modulation scheme has a lower m-ary modulation value than the first modulation scheme, and the third modulation scheme has a lower m-ary modulation value than the second modulation scheme. The transmitting apparatus also includes a pilot signal generating section that generates a pilot signal having one of a plurality of amplitudes, the pilot signal having a lower amplitude than a maximum amplitude of the first modulation scheme. The transmitting apparatus further includes a selection section that selects the modulation signal or the pilot signal according to a frame timing signal and generates a transmission quadrature baseband signal, a radio section that converts the transmission quadrature baseband signal to a radio signal, an amplifying section that amplifies the radio signal, and an antenna section that transmits the amplified radio signal. | 08-18-2011 |
20120236962 | RADIO COMMUNICATION APPARATUS CAPABLE OF SWITCHING MODULATION SCHEMES - A transmitting apparatus, includes a signal generator that generates a modulation signal by modulating transmission data using one of a plurality of modulation schemes, a first modulation scheme having a higher m-ary modulation value than other modulation schemes and a pilot signal generator generates a pilot signal. An orthogonal frequency division multiplexing (OFDM) signal generator generates an OFDM signal by selecting the modulation signal and the pilot signal according to the frame timing signal. The OFDM signal is converted to a radio signal, is amplified and is transmitted to an antenna. The pilot signal is inserted in the OFDM signal per a predetermined OFDM symbol and per a predetermined subcarrier and has a lower amplitude than a maximum amplitude of the first modulation scheme in an in-phase-quadrature (IQ) plane. | 09-20-2012 |
Patent application number | Description | Published |
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 |
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 |
Patent application number | Description | Published |
20100118745 | WIRELESS COMMUNICATION APPARATUS - In a wireless communication apparatus adopting a time division duplex system for executing transmission and reception using a plurality of antennas, deviation of amplitude and phase occurring between transmission and reception circuits is detected and corrected using a communication signal. Channel estimation means 105 detects channel information based on reception output of reception circuits 104-1 to 104-N provided in a one-to-one correspondence with a plurality of antennas 101-1 to 101-N. Correction value detection means 110 finds a correction value for correcting deviation occurring between each of transmission circuits 103-1 to 103-N and each of the reception circuits 104-1 to 104-N based on the channel information. A wireless communication apparatus 100 transmits an already known signal (training signal) to a base station with which the wireless communication apparatus conducts communications. The base station executes channel estimation based on the already known signal and generates and transmits a correction signal (probe signal). The correction value detection means 110 of the wireless communication apparatus 100 detects the correction value using the correction signal (probe signal). | 05-13-2010 |
20120213131 | WIRELESS COMMUNICATION APPARATUS - Wireless communication apparatus adopting a time division duplex system for transmission and reception using plural antennas, deviation of amplitude and phase occurring between transmission and reception circuits is detected and corrected using a communication signal. Channel estimation means detects channel information based on reception output of N reception circuits having a one-to-one correspondence with N antennas. Correction value detection means finds a correction value for correcting deviation occurring between each of N transmission circuits and each of the N reception circuits based on the channel information. A wireless communication apparatus transmits an already known signal (training signal) to a base station with which the wireless communication apparatus conducts communications. The base station executes channel estimation based on the already known signal and generates and transmits a correction signal (probe signal). The correction value detection means of the wireless communication apparatus detects the correction value using the correction signal. | 08-23-2012 |
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 |
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 |
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 |