Abstract: According to one aspect of the present invention, there is provided a wireless communication device that transmits a first wireless signal representing a bit sequence to a reception device, in which the first wireless signal is transmitted concurrently with a second wireless signal representing the bit sequence described above, and in which between the first wireless signal and the second wireless signal, components with a prescribed ratio are mapped to a different frequency or to a different time between the first wireless signal and the second wireless signal and remaining components are mapped to the same frequency and to the same time between the first wireless signal and the second wireless signal.

Abstract: A reception unit for receiving a signal representing a bit sequence, a channel estimation unit for estimating channel variation that the received signal undergoes and calculating a channel estimation value representing the channel variation, and a demodulation unit for demodulating the signal by using the channel estimation value and restoring each bit included in the bit sequence represented by the received signal are included, and the demodulation unit performs demodulation of the received signal by using a value indicating magnitude of error included in the channel estimation value.

Abstract: A reception device comprises a reception unit for receiving signals transmitted by assigning respectively a plurality of different frequency signal groups, which are generated based on a same bit sequence, to a plurality of layers, an MIMO separation unit for executing MIMO separation of the signals, received by the reception unit, into the frequency signal groups corresponding respectively to the plural layers, and a merging unit for merging individual items of information based on the frequency signal groups obtained by the MIMO separation, the items of information corresponding respectively to the plural layers.

Abstract: A bit coding device that creates a coded bit sequence by performing error correction coding on an input bit sequence that is input, includes a coding unit that creates a first bit sequence by performing the error correction coding on the input bit sequence, an extraction unit that extracts a second bit sequence from the first bit sequence, and an information compression unit that creates a third bit sequence by performing lossy compression on the second bit sequence, in which coded bits include at least a portion of the third bit sequence.

Abstract: A wireless communication system includes a first communication device and a second communication device, in which the first communication device includes a cyclostationarity assignment unit that establishes a correlation between signals on two subcarriers that are a predetermined interval away from each other, the two subcarriers including at least one subcarrier on which a data signal to be transmitted to the second communication device is arranged, and the second communication device includes a frequency interval determination unit that determines the predetermined frequency interval according to information that has to be notified to a different device by the first communication device. Thus, a communication system is provided that is capable of suppressing a decrease in frame efficiency when assigning cyclostationarity.

Abstract: To provide a system that can accommodate a greater number of terminals within a limited band and can obtain a higher transmission rate. While the number of frequency signals (spectrums) output in parallel by performing a spread spectrum from the DFT unit of each terminal is 12, the number of sub-carriers constituting one sub-channel is set at 10 or 11. In this case, the users (users A and G) allocated to the sub-channels at both ends of the band will not perform transmission of one frequency signal at the end (one sub-carrier) of all the frequency signals output from the DFT unit, whereas the users (users B to F) allocated to the other sub-channels will not perform transmission of the frequency signals at the ends (two sub-carriers). This transmission can be realized by deleting (clipping) the associated number of signals from both ends or from one end of the frequency signals output from the DFT unit of each terminal and allocating the frequency signals after clipping, to individual sub-channels.

Abstract: A communication device includes a turbo encoding section including a plurality of component encoders, wherein the plurality of component encoders within the turbo encoding section use different constraint lengths.

Abstract: An apparatus generating a packet of signals, a number of preamble signals of a preamble portion for each of a number of radio transmission units, and a number of data signals of a data portion, wherein a phase rotation in frequency domain is equal to a time shift in time domain is applied to each symbol of the number of preamble signals separately, the same phase rotation is applied to each symbol separately, the amount of the phase rotation is different for each preamble signal and each data signal, the amount of the phase rotation of one of the number of data signals and one of the number of preamble signals is both zero, and the amount of the phase rotation is equal between one of the preamble signals and one of the data signals for the same radio transmission unit.

Abstract: A wireless communication system includes: a multiple number of mobile station apparatuses that transmit code bits obtained by applying error-correction coding to information bits; a relay station apparatus that receives code bits from the multiple mobile station apparatuses, applies network coding on the code bits and transmits the network-code bits; and a base station apparatus that receives and decodes the code bits and the network-code bits, wherein the base station apparatus, when decoding the received code bits, performs iteration decoding by regarding the received code bits as a serially concatenated code of network coding and error correction coding. Accordingly, decoding is performed by regarding the network code and the error correction code as a serial concatenated code, it is possible to obtain diversity with a simple configuration.

Abstract: A communication device comprising a transmission unit and a reception unit. The transmission unit is configured to transmit, to a first communication device, first information indicating a first set of subcarriers comprising of a plurality of subcarriers, and to a second communication device, second information indicating a second set of subcarriers comprising of a plurality of subcarriers. The reception unit is configured to receive a first Discrete Fourier Transform-spread-OFDM (DFT-S-OFDM) signal from the first communication device using the first information and a second Discrete Fourier Transform-spread-OFDM (DFT-S-OFDM) signal from the second communication device using the second information. Also, in the communication device, a portion of the second set of subcarriers can overlap with at least a portion of the first set of subcarriers in a time frame of a plurality of time frames.

Abstract: Improving the accuracy of estimation of channel responses in receiving signals from a plurality of antennas is disclosed. A transmitting device of a base station includes a preamble A generating unit 010, a preamble B generating unit 011, phase rotating units 012 and 013, multiplexing units 014 and 015, an forward error correction coding unit 016, an S/P converting unit 017, a mapping unit 018, a changeover switch 019, IDFT (or IFFT) units 020 and 026, P/S converting units 021 and 027, GI (Guard Interval) inserting units 022 and 028, D/A converting units 023 and 029, radio transmitting units 024 and 030 and antenna units 025 and 031. In the preamble A generating unit 010 and the preamble B generating unit 011, a preamble A and a preamble B (see the packet format in FIG. 1) are generated, respectively. The preamble A is outputted to the multiplexing units 014 and 015, while the preamble B is outputted to the phase rotating units 012 and 013.

Abstract: A transmission method according to the present invention has been conceived assuming an environment where two information source nodes independently communicate with one destination node, and thus is applicable to such a simple topology. The transmission method provides an inter-node cooperation relationship which provides a sufficient advantageous effect even in an environment in which there is a difference in the power levels of the received signals that reach the address node via two routes. The transmission method is performed by a node U1 (40) and a node U2 that is located closer to the node D (60) than the node U1 (40) to transmit signals to a node D (60) which iteratively detects a log likelihood ratio between mutually corresponding pairs of bits included in the signals at constellation points.

Abstract: To improve performance of a decoder even in a system with the coder configuration determined by inserting a doping bit sequence known between a transmission apparatus and a reception apparatus in an information bit sequence to transmit, the transmission apparatus is a transmission apparatus that transmits radio signals to the reception apparatus, and is provided with a doping section 23 that inserts a doping bit sequence which is known between the transmission apparatus and the reception apparatus in an information bit sequence to transmit to the reception apparatus, coding sections 11a, 11b that perform error-correcting coding on a bit sequence with the doping bit sequence inserted therein, a puncturing section that performs puncturing on a bit sequence subjected to the error-correcting coding, and a wireless transmission section 24 that transmits a bit sequence subjected to the puncturing.

Abstract: A base station device may include, but is not limited to: a mapping unit; and at least one reception antenna. The mapping unit is configured to assign a plurality of first subcarriers to a first communication device, and assign a part of the plurality of first subcarriers to at least one other communication device. The at least one reception antenna is configured to receive from one of the first communication device and the at least one other communication device, a plurality of frequency signals allocated to the plurality of first subcarriers. Each of the plurality of frequency signals is converted from coded transmission data of the one of the first communication device and the at least one other communication device.

Abstract: A radio communication system converts a time domain signal into a plurality of frequency signals to be allocated onto a plurality of subcarriers to be transmitted. The radio communication system changes a method of allocating the plurality of frequency signals onto the plurality of subcarriers based on transmission power information.

Abstract: A radio communication system converts a time domain signal into a plurality of frequency signals to be allocated onto a plurality of subcarriers to be transmitted. The radio communication system changes a method of allocating the plurality of frequency signals onto the plurality of subcarriers based on transmission power information.

Abstract: A reception device comprises a reception unit for receiving signals transmitted by assigning respectively a plurality of different frequency signal groups, which are generated based on a same bit sequence, to a plurality of layers, an MIMO separation unit for executing MIMO separation of the signals, received by the reception unit, into the frequency signal groups corresponding respectively to the plural layers, and a merging unit for merging individual items of information based on the frequency signal groups obtained by the MIMO separation, the items of information corresponding respectively to the plural layers.

Abstract: The DFT 12 converts a modulated digital signal into a spectrum of a frequency band. A use frequency band notification unit in a reception device notifies a transmission device 1 of a use frequency band. A deletion unit 141 in the transmission device 1 deletes a spectrum of a band other than the use frequency band after shaping of a spectrum waveform based on the water filling principal by a shaping unit 13. Then, a digital signal for each data series concerning the spectrum obtained after deletion by the deletion unit 141 is synthesized by a synthesizing unit 16 and sent from the transmission device 1 to the reception device. A reception side conversion unit in the reception device converts the digital signal sent by the transmission unit into a spectrum of a frequency band. A turbo equalization unit performs turbo equalization on the converted spectrum.

Abstract: Improving the accuracy of estimation of channel responses in receiving signals from a plurality of antennas is disclosed. A transmitting device of a base station includes a preamble A generating unit 010, a preamble B generating unit 011, phase rotating units 012 and 013, multiplexing units 014 and 015, an forward error correction coding unit 016, an S/P converting unit 017, a mapping unit 018, a changeover switch 019, IDFT (or IFFT) units 020 and 026, P/S converting units 021 and 027, GI (Guard Interval) inserting units 022 and 028, D/A converting units 023 and 029, radio transmitting units 024 and 030 and antenna units 025 and 031. In the preamble A generating unit 010 and the preamble B generating unit 011, a preamble A and a preamble B (see the packet format in FIG. 1) are generated, respectively. The preamble A is outputted to the multiplexing units 014 and 015, while the preamble B is outputted to the phase rotating units 012 and 013.

Abstract: A clipping rate is controlled in spectrum shaping according to a propagation path to thereby improve transmission characteristics and perform communication at a stable transmission rate. Propagation path characteristics are detected by a propagation path information detection unit 5 for detecting propagation path information fed back from a base station device and a water filling principle for distributing energy by a primary spectrum shaping unit 6 according to the propagation path characteristics is applied to transmission spectrum obtained by a DFT unit 4. Clipping information in secondary spectrum shaping fed back from the base station device is detected by a clipping information detection unit 7 to perform the secondary spectrum shaping by a secondary spectrum shaping unit 8. At this time, with the clipping rate by the secondary spectrum shaping unit 8, clipping rates of all transmission devices multiplexed in a scheduling unit 26 of the base station device are controlled adaptively.