Abstract: A method performed by a transmission device and a reception device in a wireless communication system, the method including: executing a process for receiving a reference signal, which is transmitted from each of plural transmit antennas of the transmission device, through a specific receive antenna which is one of at least one receive antenna of the reception device; executing a process for deciding a transmit antenna weight and a receive antenna weight based on the reference signal, the transmit antenna weight and the receive antenna weight being applied in a case where only the specific receive antenna receives a signal which is transmitted by each of the plural transmit antennas based on same transmission data; and executing a process for transmitting first information about the transmit antenna weight and second information about the receive antenna weight to the transmission device.

Abstract: A transmission control device includes a memory and a processor connected to the memory. The processor executes a process including: selecting a reference transmission point as a starting point of generating a link from among a plurality of transmission points of which each wirelessly transmits a signal; sequentially selecting the transmission points one by one for each hierarchy corresponding to a number of hops from the selected reference transmission point and retrieving ones of the transmission points for which radio quality between the ones and the selected transmission point satisfies a predetermined criterion; and generating a link between the selected transmission point and a transmission point, among the transmission points obtained as a result at the retrieving, not connected to others of the transmission points to connect the two transmission points.

Abstract: A mobile station reports, based on a known signal transmitted from a base station, channel state information to the base station and performs wireless communication with the base station by spatial multiplexing. The mobile station includes: a calculating unit that calculates first precoding information corresponding to first channel state information and used in horizontal direction beam formation in the base station, second precoding information corresponding to second channel state information, and third precoding information corresponding to both of the first channel state information and the second channel state information and used in vertical direction beam formation in the base station; and a report control unit that reports the first precoding information and the third precoding information in reporting the first channel state information, and reports the second precoding information without reporting the third precoding information in reporting the second channel state information.

Abstract: The base station may selectively apply one of a first time period having a first guard period (GP) and a second time period having a second GP to time-division duplex communication with a terminal. Further, the base station may notify the terminal of information related to a timing of selectively applying one of the first time period and the second time period, and transmit a predetermined signal in the first guard period.

Abstract: According to one aspect, a base station that is connected to a plurality of transmission and reception points includes a calibrator. The calibrator calculates calibration coefficients to be multiplied on weights in beamforming communication at each of a plurality of transmission and reception points based on the beamforming communication at each of a plurality of transmission and reception points.

Abstract: A base station includes a scheduler which allocates a first radio resource and a second radio resource while the first radio resource is used to transmit a control channel signal from a wireless terminal, and the second radio resource is used to transmit from the wireless terminal a first reference signal corresponding to the control channel signal even when the wireless terminal does not transmit the control channel signal by using the first radio 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: There is a provided a wireless communication system in which multiple base station transmit the same data (PDSCH signal) in a coordinated transmission scheme. Each base station controls allocation a wireless resource that one of the remaining base station transmits a signal different from the above same data, such as a control signal or reference signal to a mobile station that is applied the coordinated transmission scheme to a mobile terminal that is different from the mobile station that is applied the coordinated transmission scheme and that is to communicate with the base station.

Abstract: A communication terminal device includes a determining unit that determines a region size of a control channel in accordance with a PHICH duration value transmitted from a base station device, and an acquiring unit that acquires, on the basis of the region size, data to be sent to the communication terminal device. A base station device includes a first control unit that updates a CFI value at a first interval, a second control unit that updates a PHICH duration value at a second interval, the second interval being greater than the first interval, and a scheduling unit that performs scheduling of, only in a subframe in which the PHICH duration value matches the CFI value, data to be sent to a communication terminal device that is outside an arrival coverage of a signal including the CFI value.

Abstract: A base station transmits by a group of antennas arranged two-dimensionally along a horizontal direction and a vertical direction, a data signal weighted for each antenna and transmits by first plural antennas arranged along the horizontal direction, a first reference signal weighted corresponding to the data signal and specific to a mobile station. The base station transmits a second reference signal that is common to mobile stations, via second plural antennas arranged along the vertical direction at positions corresponding to some of the first plural antennas. The base station transmits weight information that indicates a weight for the data signal for each of the antennas arranged along the vertical direction. The mobile station demodulates the data signal transmitted by the base station, based on the first reference signal, the second reference signal, and the weight information transmitted by the base station.

Abstract: A wireless communication method including: transmitting a first control signal from a connected wireless station to a wireless terminal, the connected wireless station being one of a plurality of wireless stations that is connected to the wireless terminal, the first control signal relating to a communication level between the wireless terminal and at least one wireless station that is selected from among the plurality of the wireless station, and controlling, by the wireless terminal that receives the first control signal, a transmission power of a transmission signal to the selected at least one wireless station based on the received first control signal.

Abstract: A base station apparatus includes a processor. The processor executes a process including obtaining information indicating a radio status of each mobile station apparatus relevant to first communication in which radio communication is performed between the mobile station apparatuses via the base station apparatus, and second communication in which radio communication is directly performed between the mobile station apparatuses without via the base station apparatus; and notifying, based on the obtained information, the mobile station apparatuses that perform the second communication of control information for controlling the second communication.

Abstract: A first wireless device that performs wireless communication with a wireless base station transmits identification information of the first wireless device using a radio resource allocated for device-to-device communication that is performed between the second wireless devices without going through the wireless base station.

Abstract: A first wireless device that performs wireless communication with a wireless base station transmits a signal, a second wireless device that performs device-to-device communication without going through the wireless base station receives the signal, and information of a radio resource of the received signal that is relatively higher in interference level for the device-to-device communication is transmitted to the wireless base station.

Abstract: A wireless system includes a plurality of terminals and a wireless base station. Each of the plurality of terminals determines a priority of a local terminal related to transmission of a certain signal according to a certain rule when the certain signal is not received from the wireless base station.

Abstract: A wireless communications system includes a base station configured to switch a first state of storing to control information transmitted to a terminal, a value instructing a transmission power of the terminal, and a second state of storing to the control information, a value instructing a transmission count of multiple transmissions of a same data by the terminal; and the terminal configured to switch a third state of adjusting the transmission power based on the value stored to the control information received from the base station in the first state, and a fourth state of adjusting the transmission count of multiple transmissions of the same data by the terminal, based on the value stored to the control information received from the base station in the second state.

Abstract: A communication system includes a first communication terminal and a second communication terminal that performs direct communication with the first communication terminal. The first communication terminal controls transmission power of a second reference signal which is a partial reference signal among a plurality of reference signals so as to reach known transmission power, the plurality of reference signals being transmitted with first data and used for demodulating the first data, controls transmission power of a first reference signal which is another reference signal other than the second reference signal among the plurality of reference signals so as to reach transmission power linked to transmission power of the first data, and transmits the plurality of reference signals subjected to transmission power control to the second communication terminal.

Abstract: A wireless communication system including a transmitting and receiving device that performs communications with the transmitting device, using a radio frame containing control information and data, wherein the transmitting device includes: a first generating unit that generates first control information able to be estimated by the receiving device; a second generating unit that generates second control information used for control of communication from the receiving device to the transmitting device and unable to be estimated by the receiving device; a multiplexing unit that multiplexes the control and data information so that the first control information is allocated in the control information and the second control information is allocated in the data in the radio frame; a transmitting unit a signal multiplexed by the multiplexing unit; the receiving device includes a receiving unit that receives the signal wherein the second control information is allocated in the data from the transmitting device.

Abstract: A communication apparatus includes a memory, and a processor coupled to the memory and configured to receive a first reception signal and a second reception signal in a first period, calculate a first phase rotation quantity between the first reception signal and the second reception signal, receive a third reception signal and a fourth reception signal in a second period, calculate a second phase rotation quantity between the third reception signal and the fourth reception signal, determine whether to compensate for a frequency offset of a fifth reception signal based on a difference between the first phase rotation quantity and the second phase rotation quantity, and when it is determined to compensate for the frequency offset of the fifth reception signal, compensate for the frequency offset of the fifth reception signal.

Abstract: A communication system includes a first communication terminal and a second communication terminal that performs direct communication with the first communication terminal. The first communication terminal controls transmission power of a second reference signal which is a partial reference signal among a plurality of reference signals so as to reach known transmission power, the plurality of reference signals being transmitted with first data and used for demodulating the first data, controls transmission power of a first reference signal which is another reference signal other than the second reference signal among the plurality of reference signals so as to reach transmission power linked to transmission power of the first data, and transmits the plurality of reference signals subjected to transmission power control to the second communication terminal.