Abstract: Provided are communication apparatus and a communication method that allow for secure communication even in a case that an eavesdropper has multiple antennas. An apparatus includes a transmitter configured to transmit a constant amplitude signal from three or more transmit antennas; a controller configured to control a phase of the constant amplitude signal, based on channel information and a target symbol; and a modulation unit configured to generate a modulation symbol from bits. The target symbol is generated by multiplying the modulation symbol by an amplitude coefficient.

Abstract: Provided are communication apparatus and a communication method that allow for secure communication even in a case that an eavesdropper has multiple antennas. An apparatus includes a transmitter configured to transmit a constant amplitude signal from three or more transmit antennas; a controller configured to control a phase of the constant amplitude signal, based on channel information and a target symbol; and a modulation unit configured to generate a modulation symbol from bits. The target symbol is generated by multiplying the modulation symbol by an amplitude coefficient.

Abstract: Provided is a terminal apparatus including: a receiver configured to detect a transmission direction of a signal used for communication with at least one base station apparatus; and a transmitter configured to transmit, to a location server, base station direction information for indicating the transmission direction detected.

Abstract: Provided is a terminal apparatus including: a receiver configured to detect a transmission direction of a signal used for communication with at least one base station apparatus; and a transmitter configured to transmit, to a location server, base station direction information for indicating the transmission direction detected.

Abstract: A reception apparatus that receives a transmission signal, which is transmitted from a transmission apparatus by using a MIMO transmission scheme, includes a stream selection unit that divides streams transmitted by the transmission apparatus into a first stream group and a second stream group; and a transmission candidate search unit that generates at least one candidate of the first stream group, generates a linear detection signal of the second stream group based on the candidate of the first stream group to generate transmission candidates, calculates metrics of the transmission candidates, and selects a transmission candidate, a metric of which is minimum, of the transmission candidates.

Abstract: The present invention is capable of reducing a calculation amount while lessening performance degradation from MLD. The present invention is a reception device that receives a transmit signal which is transmitted from a transmission device by a MIMO transmission scheme. The reception device includes a channel estimation unit (205) that performs channel estimation using a received signal, and calculates a channel estimation value, a signal detection unit (206) that generates a bit log-likelihood ratio by MIMO demultiplexing of a received signal based on the channel estimation value, and a decoding unit (207) that performs error correction decoding with respect to the bit log-likelihood ratio.

Abstract: The present invention is capable of reducing a calculation amount while lessening performance degradation from MLD. The present invention is a reception device that receives a transmit signal which is transmitted from a transmission device by a MIMO transmission scheme. The reception device includes a channel estimation unit (205) that performs channel estimation using a received signal, and calculates a channel estimation value, a signal detection unit (206) that generates a bit log-likelihood ratio by MIMO demultiplexing of a received signal based on the channel estimation value, and a decoding unit (207) that performs error correction decoding with respect to the bit log-likelihood ratio.

Abstract: A receiving device, a receiving method, and a receiving program are provided and are capable of reducing performance degradation in a case where the spatial correlation of a channel becomes high. A transmission signal candidate search unit searches for a transmission signal in a direction in which reception performance is degraded, in MIMO signal detection. A transmission signal candidate generation unit generates transmission signal candidates while suppressing degradation due to the spatial correlation of a channel. In a decision unit, using the transmission signal candidates generated in the transmission signal candidate generation unit, a maximum likelihood sequence is obtained. The maximum likelihood sequence is obtained as transmission signal candidates where a metric is calculated and the metric becomes a minimum.

Abstract: To provide a receiving device, a receiving method, and a receiving program, which are capable of reducing performance degradation in a case where the spatial correlation of a channel becomes high. A transmission signal candidate search unit searches for a transmission signal in a direction in which reception performance is degraded, in MIMO signal detection. A transmission signal candidate generation unit generates transmission signal candidates while suppressing degradation due to the spatial correlation of a channel. In a decision unit, using the transmission signal candidates generated in the transmission signal candidate generation unit, a maximum likelihood sequence is obtained. The maximum likelihood sequence is obtained as transmission signal candidates where a metric is calculated and the metric becomes a minimum.

Abstract: A receiver apparatus receiving a quadrature-modulated, modulated wave, includes: a real-zero signal generator for adding a sinusoidal wave to the modulated wave to generate a real-zero signal; an in-phase and quadrature component detector for extracting an in-phase component signal and a quadrature component signal from the real-zero signal; a real-zero sequence generator for generating a real-zero sequence as a sequence of time points at which the in-phase component and quadrature component signals become zero; and a signal reconstruction unit for reproducing the in-phase component and quadrature component from the real-zero sequence. It is possible to provide a receiving apparatus that enables decoding of a received signal with high precision even when sufficient linearity cannot be secured in the analog circuit of the receiver apparatus.

Abstract: A wireless communication device that transmits a wireless signal by carrying out linear precoding processing using a plurality of transmission antennas is provided with: a phase pattern control unit for selecting a phase pattern that reduces peak-to-average power ratio; a phase rotation unit for carrying out phase rotation on a modulation signal using the phase pattern selected in the phase pattern control unit; a control signal generation unit for generating a control signal based on the phase pattern selected in the phase pattern control unit; and a preceding unit for carrying out linear precoding processing on output signals from the phase rotation unit and output signals from the control signal generation unit.

Abstract: To obtain excellent reception performance while cutting down the amount of computing operation in a MIMO communication system using soft-decision error correction coding. Received waves picked up by receiving antennas 401-1 to 401-R are converted from the radio frequency to the baseband signal by respective receivers 402-1 to 402-R to be output as a received signal. A signal detector 403 calculates bit LLRs of the transmitted signal based on the received signal and the channel-estimated values obtained from a channel estimator 404. The bit LLRs output from signal detector 403 are rearranged by deinterleaver units 405-1 to 405-T in the patterns opposite to the patterns in which interleaving was performed on the transmission side. The bit LLRs after de-interleaving are subjected to an error correction decoding process through decoders 406-1 to 406-T. The bit sequences after decoding are parallel-to-serial converted by a parallel-to-serial converter 407 so that the detected transmission bit sequence is output.

Abstract: A receiving apparatus and reception method reduces degradation due to multipath interference without increasing the amount of computation even in a system that has a large number of subcarriers. A signal detector, using the symbol replica generated by symbol replica generator and the channel estimate which a channel estimator estimated based on the received pilot signal, suppresses interference attributed to delayed waves exceeding the GI and outputs a suppressed signal for the received signal. A demodulator decodes the signal of which interference has been alleviated, to determine code bit LLR as bit likelihood information. A decoder performs an error correction decoding process on the input code bit LLR. If no error exists in the result of error correction decoding, the decoder outputs information bits to complete the reception process. If there is an error in the decoded result, the decoder outputs the code bit LLR to symbol replica generator.

Abstract: A receiver apparatus 200 receiving a quadrature-modulated, modulated wave, includes: a real-zero signal generator 205 for adding a sinusoidal wave to the modulated wave to generate a real-zero signal; an in-phase and quadrature component detector 206 for extracting an in-phase component signal and a quadrature component signal from the real-zero signal; a real-zero sequence generator 207 for generating a real-zero sequence as a sequence of time points at which the in-phase component and quadrature component signals become zero; and a signal reconstruction unit 208 for reproducing the in-phase component and quadrature component from the real-zero sequence. With this, it is possible to provide a receiving apparatus etc. that enables decoding of a received signal with high precision even when sufficient linearity cannot be secured in the analog circuit of the receiver apparatus.

Abstract: To obtain excellent reception performance whilst cutting down the amount of computing operation in a MIMO communication system using soft-decision error correction coding. Received waves picked up by receiving antennas 401-1 to 401-R are converted from the radio frequency to the baseband signal by respective receivers 402-1 to 402-R to be output as a received signal. A signal detector 403 calculates bit LLRs of the transmitted signal based on the received signal and the channel-estimated values obtained from a channel estimator 404. The bit LLRs output from signal detector 403 are rearranged by deinterleaver units 405-1 to 405-T in the patterns opposite to the patterns in which interleaving was performed on the transmission side. The bit LLRs after de-interleaving are subjected to an error correction decoding process through decoders 406-1 to 406-T. The bit sequences after decoding are parallel-to-serial converted by a parallel-to-serial converter 407 so that the detected transmission bit sequence is output.

Abstract: A radio communication apparatus for performing transmission and reception based on radio communication includes: a power suppressor for coupling loop interference signal for attenuating signal power of a received signal to suppress the coupling loop interference signal power of the received signal; and a transceiver having a coupling loop interference signal removal function for analog domain and/or a coupling loop interference signal removal function for digital domain, for removing a coupling loop interference signal contained in a signal output from the power suppressor for coupling loop interference signal.

Abstract: A radio communication apparatus for performing transmission and reception of radio communications simultaneously by using different carrier frequencies for transmission and reception, comprising: a transceiver having a coupling loop interference signal removal function for analog domain and/or a coupling loop interference signal removal function for digital domain, for removing a coupling loop interference signal contained in a signal; and a power suppressor for coupling loop interference signal for attenuating the signal power in order to suppress the coupling loop interference signal power that is contained in the signal.

Abstract: A wireless communication device that transmits a wireless signal by carrying out linear precoding processing using a plurality of transmission antennas is provided with: a phase pattern control unit for selecting a phase pattern that reduces peak-to-average power ratio; a phase rotation unit for carrying out phase rotation on a modulation signal using the phase pattern selected in the phase pattern control unit; a control signal generation unit for generating a control signal based on the phase pattern selected in the phase pattern control unit; and a preceding unit for carrying out linear precoding processing on output signals from the phase rotation unit and output signals from the control signal generation unit.

Abstract: An object is to provide a wireless communication device and a wireless communication method enabling improvement of communication efficiency. A communication control portion of a mobile station determines, in a procedure prior to data communication with a base station, a time interval for performing data transmission/reception with the base station. In the time interval determined by the communication control portion, a digital baseband circuit 107 executes control so as to perform data transmission as well as data reception.

Abstract: A radio communication apparatus for performing transmission and reception of radio communications simultaneously by using different carrier frequencies for transmission and reception, comprising: a transceiver having a coupling loop interference signal removal function for analog domain and/or a coupling loop interference signal removal function for digital domain, for removing a coupling loop interference signal contained in a signal; and a power suppressor for coupling loop interference signal for attenuating the signal power in order to suppress the coupling loop interference signal power that is contained in the signal.