Abstract: A transmission apparatus includes an encoder that codes a data sequence with a parity check matrix, wherein the data sequence includes a final information bit sequence and virtual information bits, and outputs the final information bit sequence and a parity sequence, as LDPC codes, and a transmitter that transmits the LDPC codes as a transmission data. A column length of the parity check matrix is longer than a total length of the final information bit sequence and the parity sequence, by a length of the virtual information bits that are set to “0” and are not transmitted. The total length of the final information bit sequence and the parity sequence has a sequence length corresponding to a length from a first column to a determined column of the parity check matrix. The encoder generates the LDPC codes by using the first column to the determined column among one or more column(s) of the parity check matrix.

Abstract: A transmission apparatus includes orthogonal frequency division multiplexing (OFDM) modulation signal generating circuitry. The circuitry generates a first OFDM modulation signal by inserting symbols for demodulation in a first plurality of subcarriers at a first time and in a second plurality of sub-carriers at a second time adjacent to the first time, the symbols for demodulation being reception processing reference symbols of a reception apparatus, and, inserting symbols, having both an in-phase (I) component and a quadrature-phase (Q) component in an I-Q plane of zero, in the second plurality of sub-carriers at the first time and in the first plurality of sub-carriers at the second time.

Abstract: 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.

Abstract: A plurality of modulation signals is generated. Each of the plurality of modulation signals includes a pilot symbol sequence having a plurality of pilot symbols. Each pilot symbol sequence is inserted at a same temporal point in each modulation signal, and each pilot symbol in the pilot symbol sequence has a non-zero amplitude. A quantity of the plurality of pilot symbols in each pilot symbol sequence is greater than or equal to a quantity of the plurality of modulation signals to be transmitted. The plurality of modulation signals are transmitted in an identical frequency band from a plurality of antennas. Each of the transmitted plurality of modulation signals includes transmission data and one of the pilot symbol sequences.

Abstract: A low-density parity check convolution code (LDPC-CC) is made, and a signal sequence is sent after being subjected to an error-correcting encodement using the low-density parity check convolution code. In this case, a low-density parity check code of a time-variant period (3g) is created by linear operations of first to 3g-th (letter g designates a positive integer) parity check polynomials and input data.

Abstract: A transmitter apparatus wherein a simple structure is used to successfully suppress the degradation of error rate performance that otherwise would be caused by fading or the like. There are included encoding parts that encode transport data; a mapping part that performs such a mapping that encoded data sequentially formed by the encoding parts are not successively included in the same symbol, thereby forming data symbols; and a symbol interleaver that interleaves the data symbols. In this way, a low computational complexity can be used to perform an interleaving process equivalent to a bit interleaving process to effectively improve the reception quality at a receiving end.

Abstract: 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.

Abstract: A transmission apparatus maps a first stream of input data to first complex symbols in serial format and convert them into first complex symbols in parallel format. They are inverse Fourier transformed into OFDM signals associated with multiple subcarriers that are transmitted via a first antenna over the multiple subcarriers in a same frequency band over a same time period that includes a same set of time slots. First pilot information is transmitted via a first antenna on a first one of a plurality of pilot subcarriers during the same set of time slots, and second pilot information is sent via a first antenna on a second one of a plurality of pilot subcarriers during the same set of time slots. The second pilot information is different from the first pilot information. A second stream of input data is similarly transformed to form second OFDM signals transmit via a second antenna over the multiple subcarriers in the same frequency band over the same time period that includes the same set of time slots.

Abstract: A first radio signal is received that was transmitted from a first antenna at a transmitter and a second radio signal transmitted from a second antenna at the transmitter different from the first antenna. The first radio signal is converted to a first orthogonal frequency division multiplexing (OFDM) frame signal, and the second radio signal is converted to a second OFDM frame signal. The first OFDM frame signal includes a grid of multiple frequency subcarriers and time periods, each time period with the frequency carriers corresponding to a first OFDM symbol such that the first OFDM frame includes first OFDM symbols. A first OFDM symbol is carried on frequency subcarriers during a time period, and the first OFDM frame includes first reference OFDM symbols located at corresponding time-frequency resource elements in the grid. Each resource element is defined by a one of the frequency subcarriers and one of the time periods.

Abstract: A low-density parity check convolution code (LDPC-CC) is made, and a signal sequence is sent after being subjected to an error-correcting encodement using the low-density parity check convolution code. In this case, a low-density parity check code of a time-variant period (3g) is created by linear operations of first to 3g-th (letter g designates a positive integer) parity check polynomials and input data.

Abstract: A transmission apparatus includes processing circuitry that generates a first data sequence representing first data or a second data sequence representing second data different from the first data and selects the first data sequence as an output data sequence. A modulation scheme is determined from a plurality of modulation schemes, and the output data sequence is modulated with the determined modulation scheme. Transmission circuitry transmits the modulated output data sequence. A first time interval associated with selecting the first data sequence for the output data sequence is longer than a second time interval associated with determining the determined modulation scheme.

Abstract: Multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) communication is provided which allows high accuracy estimation of frequency offset, high accuracy estimation of a transmission path fluctuation and high accuracy synchronization/signal detection. Pilot symbol mapping is provided for forming pilot carriers by assigning orthogonal sequences to corresponding subcarriers among OFDM signals which are transmitted at the same time from respective antennas in the time domain. Even when pilot symbols are multiplexed among a plurality of channels (antennas), this allows frequency offset/phase noise to be estimated with high accuracy.

Abstract: 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.

Abstract: A first orthogonal frequency division multiplexing (OFDM) frame signal is generated that includes a grid of multiple frequency subcarriers and multiple time periods. An OFDM symbol is transmitted using multiple frequency subcarriers during a time period and includes known reference OFDM symbols assigned to corresponding time-frequency resource elements in the grid, Each resource element is defined by a one of the multiple frequency subcarriers and one of the multiple time periods. A second orthogonal frequency division multiplexing (OFDM) frame signal is generated that includes a grid of multiple frequency subcarriers and multiple time periods and includes known reference OFDM symbols assigned to corresponding time-frequency resource elements in the grid.

Abstract: A transmission apparatus includes a plurality of antennas and a transmission scheme determination processor that selects one of either a first transmission scheme of transmitting a plurality of signals including a first amount of data in a frame, respectively, from the plurality of antennas, and a second transmission scheme of transmitting a plurality of signals including a second greater amount of data in a frame, respectively, from the plurality of antennas. The apparatus includes a modulation scheme selection processor that selects a modulation scheme among a plurality of modulation schemes and a control processor that controls the transmission scheme determination processor and the modulation scheme selection processor to change the transmission scheme less frequently than the modulation scheme. A transmitter transmits from the plurality of antennas a signal generated based on the selected transmission scheme and the selected modulation scheme.

Abstract: 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.

Abstract: A radio transmission apparatus includes a first antenna, a second antenna, and circuitry configured, based on information associated with an estimated communications channel condition, to generate a single modulation signal or a plurality of modulation signals based on the estimated communications channel condition information, and to (i) transmit the single modulation signal from the first antenna or (ii) transmit the plurality of modulation signals which include different information from each other over an identical frequency band from the first antenna and the second antenna at an identical temporal point. The single modulation signal and the plurality of modulation signals contain parameter information indicating a number of modulation signals transmitted at the same time.

Abstract: A transmitter apparatus wherein a simple structure is used to successfully suppress the degradation of error rate performance that otherwise would be caused by fading or the like. There are included encoding parts that encode transport data; a mapping part that performs such a mapping that encoded data sequentially formed by the encoding parts are not successively included in the same symbol, thereby forming data symbols; and a symbol interleaver that interleaves the data symbols. In this way, a low computational complexity can be used to perform an interleaving process equivalent to a bit interleaving process to effectively improve the reception quality at a receiving end.

Abstract: A plurality of modulation signals is generated. Each of the plurality of modulation signals includes a pilot symbol sequence having a plurality of pilot symbols. Each pilot symbol sequence is inserted at a same temporal point in each modulation signal, and each pilot symbol in the pilot symbol sequence has a non-zero amplitude. A quantity of the plurality of pilot symbols in each pilot symbol sequence is greater than or equal to a quantity of the plurality of modulation signals to be transmitted. The plurality of modulation signals are transmitted in an identical frequency band from a plurality of antennas. Each of the transmitted plurality of modulation signals includes transmission data and one of the pilot symbol sequences.

Abstract: A radio communication apparatus includes a QPSK modulator that modulates transmission data to produce a QPSK modulation signal and a 64QAM modulator that modulates transmission data to produce a 64QAM modulation signal. A radio transmitter receives the QPSK modulation signal and the 64QAM modulation signal and outputs a transmission signal. An average transmission power of the QPSK modulation signal and the 64QAM modulation signal are within a predetermined output power range.