Abstract: A wireless communication system controls a transmission timing in each cell so that a control channel of a first cell and a data channel of a second cell temporally overlap each other. The wireless communication system includes a base station of the first cell. The base station of the first cell includes a first control unit and a first communicating unit. The first control unit notifies a base station of the second cell information used to specify a resource of the control channel of the first cell. The first control unit sets a resource of the control channel of the first cell. The first communicating unit notifies the mobile station of the first cell of information for decoding the first resource and transmits a control signal to the mobile station of the first cell by using the first resource.

Abstract: It is an object of the invention to provide a wireless communication system capable of decoding a downlink shared channel of an interfering cell while achieving the reduction of intercell interference to a downlink control channel of an interfered cell. In a wireless communication system that controls transmission timing of each base station so that a control channel transmitted by a first base station and a shared channel transmitted by a second base station temporally overlap, the second base station includes a muting control unit and a muting processing unit that transmit a null symbol in an overlapping time interval of the shared channel with a time interval of the control channel on the basis of the number of code blocks in a data signal component for each mobile station corresponding to the overlapping time interval of the shared channel with the time interval of the control channel.

Abstract: When performing communication with a mobile station using MIMO-OFDM communication, a base station uses multiple input multiple output (MIMO) communication, which is multiple data stream transmission, to transmit data and pilot signals in a case where the communication environment of the mobile station is good, or uses single input multiple output (SIMO) communication, which is single data stream transmission, in a case where the communication environment of the mobile station is poor. When performing that SIMO communication, the base station performs control so that pilot signals from a specified cell that are used in channel estimation in single data stream transmission and pilot signals from adjacent cells that are used in channel estimation in single data stream transmission do not overlap in the frequency direction and/or time axis direction.

Abstract: In a multiple-input multiple-output transmission system (MIMO system), a receive station detects whether or not there is an error in each data stream, estimates the state of the propagation path of each transmit antenna and reports, to the transmitting side, re-transmission necessary/unnecessary information, for every data stream, created based upon whether or not there is an error, and the state of the propagation path of each transmit antenna. A transmit station decides a transmit antenna that transmits a data stream requiring re-transmission, based upon the reported state of the propagation path of each transmit antenna, and re-transmits the data stream requiring re-transmission from the transmit antenna decided.

Abstract: The present invention relates to a wireless communication device performing communications by using a radio frame containing a control channel and a data channel, the wireless communication device comprises of a structuring unit that allocates a first part of the control channel adjacent to the data channel in the radio frame, and allocates a second part of the control channel, which denotes different control information from the first part, to the data channel so as to be inserted between data of the data channel and a transmission unit that transmits the radio frame including the data channel and the control channel.

Abstract: A receiving station repeatedly performs decoding processing of data in a decoding processing portion, performs error detection of the decoding results, and transmits to a transmitting station an error detection result (ACK/NACK) for decoding results for a preset number of executions, and moreover issues a request to the transmitting station to modify the data transmission interval based on the data reception characteristic. The transmitting station transmits data at transmission intervals according to the transmission interval modification requests sent from the receiving station. The receiving station selectively inputs to the decoding processing portion the data received from the transmitting station and the previous decoding result data.

Abstract: A communication system includes a communication station that converts a value information into a code value based on a corresponding relationship in which a difference between a first value information and a second value information is set to any value equal to or greater than two, where the second value information corresponds to a code value where an error occurs in one bit of the code value corresponding to the first value information.

Abstract: A modulation switching method performed in a radio communication system is disclosed. In the method, difference information between the first channel quality information fed back from the receiving station and second channel quality information used to determine a modulation method is generated and is sent as control information is sent to the receiving station, with the transmission station. Switch information from the difference information received as the control information and third channel quality information being previous information in the receiving station are acquired, and data signal is demodulated based on the switch information, with the receiving station.

Abstract: A wireless communication system includes a transmitter station and a receiver station capable of performing wireless communication via a relay station. The relay station includes a receiver that receives the signals transmitted by the transmitter station. The relay station also includes a signal processor that performs predetermined signal processing on the signals received by the receiver, and eliminates the later one of two same signals received by the receiver. The relay station further includes a transmitter that transmits the earlier one of the two same signals to the receiver station after the signal processing performed by the signal processor.

Abstract: A relay station that includes a receiver that receives, from a transmitter station, a signal in which known data used for propagation path estimation is assigned to a first region determined by a combination of a frequency domain and a time domain and predetermined data is assigned to a second region that is different from the first region. The relay station also includes a processor that performs processing for generating a signal in which the known data is assigned to the second region in the signal received by the receiver, and a transmitter that transmits the signal generated by the processor.

Abstract: The present invention relates to a wireless communication device performing communications by using a radio frame containing a control channel and a data channel, the wireless communication device comprises of a structuring unit that allocates a first part of the control channel adjacent to the data channel in the radio frame, and allocates a second part of the control channel, which denotes different control information from the first part, to the data channel so as to be inserted between data of the data channel and a transmission unit that transmits the radio frame including the data channel and the control channel.

Abstract: In a communication system, a transmitter device transmits data to a receiver device for performing error-correcting decoding processing by combining received data and retransmitted data. The transmitter device selects one of a first set of schemes of an M number of modulation and coding schemes as a modulation and coding scheme (MCS) of first data according to communication quality information obtained from the receiver device when the first data is initially transmitted, and selects one of a second set of schemes of an N number of MCSs (N<M) according to the communication quality information when the first data is retransmitted. The transmitter device generates a control signal including information indicating the selected MCS so that an amount of information of the MCS selected from the second set of schemes is less than an amount of information of the MCS selected from the first set of schemes.

Abstract: Disclosed is a feedback control method in closed-loop transmit diversity in which feedback information representing amounts of amplitude and phase control is transmitted from a mobile station to a radio base station. The mobile station receives downlink pilot signals, which are transmitted by a handover-destination base station, during handover control, calculates feedback information, which represents amounts of amplitude and phase and phase control transmitted to the handover-destination base station, beforehand based upon the pilot signals received, and transmits the feedback information to the handover-destination base station before completion of base-station changeover by handover.

Abstract: A wireless communication system in which retransmission is performed between a transmitting apparatus and a receiving apparatus, whereby the transmitting apparatus includes, a first transmitting unit to transmit first data to the receiving apparatus and retransmission controlling unit to perform transmission of second data, the data part of which is same as that of the first data, without waiting for a feedback signal from receiving apparatus regarding the first data, and to wait for a feedback signal from the receiving apparatus regarding the second data, and the receiving apparatus includes, a second transmitting unit to transmit the feedback signal regarding the second data to the transmitting apparatus.

Abstract: In multicarrier transmission for multiplying transmit data individually by each code constituting orthogonal codes and transmitting each result of multiplication by a prescribed subcarrier, a plurality of different subcarriers are assigned exclusively to each user and each user performs multicarrier transmission of the transmit data by the subcarriers assigned. Further, a base station assigns a plurality of different subcarriers to each user exclusively, applies beam-forming processing on a per-user basis and performs multicarrier transmission of transmit data to each user by the subcarriers assigned.

Abstract: A method of transmitting pilot signals for channel compensation in a mobile communication system is disclosed. In the disclosed method, a first pilot signal and a second pilot signal are time-division multiplexed together with a data signal of a user into a time-division multiplexed signal which data signal is assigned a certain bandwidth; the time-division multiplexed signal is frequency-division multiplexed together with time division multiplexed signals of other users when wirelessly transmitted; and the first pilot signal is assigned a bandwidth larger than the bandwidth of the data signal and the second pilot signal is assigned a bandwidth smaller than the bandwidth of the data signal.

Abstract: An information communication method, which is executed on a transmitting side, is provided. The method comprises a first step of transmitting communication data to a receiving side; and a second step of retransmitting the communication data to the receiving side without waiting for an arrival of a negative acknowledgement signal of the communication data, which arrives from the receiving side, or an elapse of a predetermined acknowledgement wait time.

Abstract: A radio transmission apparatus includes: a guard interval insertion unit that inserts a guard interval in every data block of a transmission data signal; a waveform shaping unit that performs a signal attenuation processing in a time period that includes a boundary of a signal block in which the guard interval has been inserted; and a controller that controls an insertion period of the guard interval by the guard interval insertion unit such that the data block is located in a time period exclusive of the time period which is a signal attenuation period by the waveform shaping unit. By this, in an environment where a signal to which a window function (band limitation) is applied may be received, while the guard intervals are effectively utilized, degradation of reception characteristics due to influence of the band limitation is prevented.

Abstract: In a multiple-input multiple-output transmission system (MIMO system), a receive station detects whether or not there is an error in each data stream, estimates the state of the propagation path of each transmit antenna and reports, to the transmitting side, re-transmission necessary/unnecessary information, for every data stream, created based upon whether or not there is an error, and the state of the propagation path of each transmit antenna. A transmit station decides a transmit antenna that transmits a data stream requiring re-transmission, based upon the reported state of the propagation path of each transmit antenna, and re-transmits the data stream requiring re-transmission from the transmit antenna decided.

Abstract: A method of transmitting pilot signals for channel compensation in a mobile communication system based on DFT-spread-OFDM is disclosed. In the disclosed method, a first pilot signal and a second pilot signal are time-division multiplexed together with a data signal of a user into a time-division multiplexed signal which data signal is assigned a certain bandwidth; the time-division multiplexed signal is frequency-division multiplexed together with time-division multiplexed signals of other users when wirelessly transmitted; and the first pilot signal is assigned a bandwidth larger than the bandwidth of the data signal and the second pilot signal is assigned a bandwidth smaller than the bandwidth of the data signal.