Abstract: According to one embodiment, a wireless communication device includes a transmitter configured to transmit a first frame including first information, the first information including information to designate a plurality of wireless communication devices and information concerning communication resources which have been assigned to the plurality of wireless communication devices for multiplexing communication and a receiver configured to receive a signal.

Abstract: According to one embodiment, a wireless communication device includes: a receiver configured to receive a plurality of first frames transmitted by spatial multiplexing; and a transmitter configured to transmit a second frame containing check results indicating whether the first frames are successfully received and first information specifying at least one communication device. The receiver is configured to receive a plurality of third frames transmitted by spatial multiplexing from a communication device having transmitted the first frame the check result of which represents failure and the communication device specified in the first information.

Abstract: A wireless communication device includes a transmitter and a receiver. The transmitter transmits a first frame containing notification information to specify first and second wireless terminals and a second frame for channel estimation. The receiver receives a third frame transmitter from the first wireless terminal and a fourth frame transmitted from the second wireless terminal. The third frame and the fourth frame are transmitted in a multiplexing scheme by the first and the second wireless terminals. The third frame contains first channel information estimated based on the second frame. The fourth frame contains second channel information estimated based on the second frame. The first frame contains at least either information to specify a preamble of the third frame and a preamble of the fourth frame or information to specify a subcarrier used for transmission of the third frame and a subcarrier used for transmission of the fourth frame.

Abstract: In one embodiment, a wireless relay apparatus for replaying a signal processed by first encoding from a transmitting apparatus to a receiving apparatus is disclosed. The apparatus includes a demodulation unit, a decoding unit, a detection unit, an extraction unit, and an encoding unit. The demodulation unit demodulates a received signal. The decoding unit performs error correction decoding corresponding to the first encoding on the demodulated signal. The detection unit detects an error in a decoded signal. The extraction unit extracts a portion pertaining to information data from the demodulated signal by hard decision, if the detection unit detects an error. The encoding unit performs error correcting coding on the extracted portion pertaining to the information data with an error. The information data encoded by the encoding unit is transmitted.

Abstract: An orthogonal frequency division multiplexing (OFDM) signal transmission apparatus which transmits OFDM signals by using a plurality of transmission antennas includes a subcarrier setting device which sets signals for subcarriers so as to use some of the subcarriers of the OFDM signals as pilot subcarriers to transmit pilot signals and use the remaining subcarriers as data subcarriers to transmit data signals, the subcarrier setting device changing polarities of signals for the pilot subcarriers for each transmission antenna.

Abstract: Allocation of terminal stations to communications channels is carried out on the basis of a selection criterion. Allocation takes account of whether the terminal station is in an edge region of a cell. If so, then the list of terminal stations to be allocated is modified, to account for any interference risk from other base stations.

Abstract: An orthogonal frequency division multiplexing (OFDM) signal transmission apparatus which transmits OFDM signals by using a plurality of transmission antennas includes a subcarrier setting device which sets signals for subcarriers so as to use some of the subcarriers of the OFDM signals as pilot subcarriers to transmit pilot signals and use the remaining subcarriers as data subcarriers to transmit data signals, the subcarrier setting device changing polarities of signals for the pilot subcarriers for each transmission antenna.

Abstract: One embodiment provides a signal processor configured to cooperate with a first apparatus having first and second antennas and a second apparatus having third and fourth antennas, including: first and second calculators for calculating first and second coefficient, respectively; first and second estimators for estimating first and second transfer functions of a path between the first and second apparatuses based on first and second weights; and a third calculator for calculating a third coefficient. The third coefficient is used with the first and second transfer functions for making a transfer function ratio regarding the first antenna, a transfer function ratio regarding the second antenna, a transfer function ratio regarding the third antenna and a fourth transfer function ratio regarding the fourth antenna same as one another.

Abstract: According to one embodiment, a wireless communication method for improving frequency efficiency is disclosed. The method can transmit a first instruction indicating that the second terminal is allowed to transmit a second data signal at the first frequency if the first signal strength intensity is not more than a threshold and if the second signal strength intensity is not more than a threshold. The method can transmit a second instruction indicating that the second terminal is caused to suspend the second data signal transmission at the first frequency in reference to the first instruction if interference occurring in a first base station as a transmission result of the second data signal is not less than a threshold.

Abstract: According to one embodiment, an allocating unit of a wireless communication device finds for each user an unallocated radio channel having maximum communication quality as a first radio channel, and calculates a first metric matching a communication state using communication quality in the first radio channel, selects one user from the plurality of users based on the first metric and allocates the first radio channel to the selected user. Further, the allocating unit repeats allocating an unallocated radio channel adjacent to a radio channel allocated to the selected user on a frequency domain until predetermined conditions are satisfied.

Abstract: In one embodiment, a wireless relay apparatus for replaying a signal processed by first encoding from a transmitting apparatus to a receiving apparatus is disclosed. The apparatus includes a demodulation unit, a decoding unit, a detection unit, an extraction unit, and an encoding unit. The demodulation unit demodulates a received signal. The decoding unit performs error correction decoding corresponding to the first encoding on the demodulated signal. The detection unit detects an error in a decoded signal. The extraction unit extracts a portion pertaining to information data from the demodulated signal by hard decision, if the detection unit detects an error. The encoding unit performs error correcting coding on the extracted portion pertaining to the information data with an error. The information data encoded by the encoding unit is transmitted.

Abstract: In one embodiment, a wireless relay apparatus for replaying a signal processed by first encoding from a transmitting apparatus to a receiving apparatus is disclosed. The apparatus includes a demodulation unit, a decoding unit, a detection unit, an extraction unit, and an encoding unit. The demodulation unit demodulates a received signal. The decoding unit performs error correction decoding corresponding to the first encoding on the demodulated signal. The detection unit detects an error in a decoded signal. The extraction unit extracts a portion pertaining to information data from the demodulated signal by hard decision, if the detection unit detects an error. The encoding unit performs error correcting coding on the extracted portion pertaining to the information data with an error. The information data encoded by the encoding unit is transmitted.

Abstract: An orthogonal frequency division multiplexing (OFDM) signal transmission apparatus which transmits OFDM signals by using a plurality of transmission antennas includes a subcarrier setting device which sets signals for subcarriers so as to use some of the subcarriers of the OFDM signals as pilot subcarriers to transmit pilot signals and use the remaining subcarriers as data subcarriers to transmit data signals, the subcarrier setting device changing polarities of signals for the pilot subcarriers for each transmission antenna.

Abstract: According to one embodiment, a wireless communication apparatus includes a calculator and a controller. The calculator multiplies a first weighting factor by a first data signal to be transmitted on a first channel, the first weighting factor is based on a second weighting factor multiplied by a second data signal received on the first channel. The controller controls a transmission to transmit to a destination device a control signal if the first data signal transmitted to the partner device exists, and no second data signal to be transmitted on the first channel exists in the device.

Abstract: An orthogonal frequency division multiplexing (OFDM) signal transmission apparatus which transmits OFDM signals by using a plurality of transmission antennas includes a subcarrier setting device which sets signals for subcarriers so as to use some of the subcarriers of the OFDM signals as pilot subcarriers to transmit pilot signals and use the remaining subcarriers as data subcarriers to transmit data signals, the subcarrier setting device changing polarities of signals for the pilot subcarriers for each transmission antenna.

Abstract: According to one embodiment, a communication device communicates with N remote units. Each remote unit includes a plurality of antennas, wireless transmitting units, and wireless receiving units. The communication device is provided with a received signal processing unit, to which received signals by a plurality of the wireless receiving units are combined and input, and which specifies the remote unit subjected to interference, and a switch which decreases a reception gain of the wireless receiving unit included in N?1 remote units out of the N remote units in a predetermined measurement section. The received signal processing unit calculates a correlation value between the combined received signals and a reference signal transmitted by a user terminal connected to another base station system in the measurement section and specifies the remote unit subjected to the interference by the second user terminal based on the correlation value.

Abstract: A wireless communication device includes a wireless communication module and an allocator. The wireless communication module wirelessly communicates with a plurality of other wireless communication devices. The allocator allocates time resources and frequency resources to a plurality of traffics which periodically occur between the wireless communication device and the plurality of other wireless communication devices in descending order of resource utilizations. The resource utilization of a given traffic corresponds to a time rate at which the given traffic uses a frequency resource allocated thereto. The allocator allocates the frequency resource, which is arranged at a position closer to an end than a center frequency, to a traffic which is the highest in resource utilization.

Abstract: According to one embodiment, a wireless communication apparatus includes a perturbation vector addition unit, a weight multiplication unit and a normalization coefficient multiplication unit. The perturbation vector addition unit is configured to add a perturbation vector only to a first data signal of a first transmission signal containing a first pilot signal and the first data signal, and obtain a second transmission signal containing a second pilot signal and a second data signal. The weight multiplication unit is configured to multiply each of the second pilot signal and the second data signal by a weight for removing interference on a reception side, and obtain a third transmission signal containing a third pilot signal and a third data signal. The normalization coefficient multiplication unit is configured to multiply each of the third pilot signal and the third data signal by a common normalization coefficient for normalizing a total transmission power.

Abstract: Allocation of terminal stations to communications channels is carried out on the basis of a selection criterion. Allocation takes account of whether the terminal station is in an edge region of a cell. If so, then the list of terminal stations to be allocated is modified, to account for any interference risk from other base stations.

Abstract: An FM receiver includes a receiving unit that receives a signal from a broadcasting station and outputs a receiving signal, an equalizer that equalizes the receiving signal by using a calculated weight, and obtains an equalized output signal, a demodulator that demodulates the equalized output signal to reproduce the signal from the broadcasting station, a detection unit that observes size of the calculated weight to detect a capture state with respect to an undesired broadcasting station and generates a capture detection signal, and a weight setting unit that sets the calculated weight with respect to the equalizer at a steady state, and sets a specific weight for temporarily setting the equalizer in a through state when the capture detection signal is generated.