Abstract: A radio communication apparatus functioning as a transmitter in a radio communication system including the transmitter and a receiver includes a first data generation unit that generates first data which are to be transmitted in accordance with a first transmission scheme, a second data generation unit that generates second data which are to be transmitted in accordance with a second transmission scheme, and a transmission unit that, when the second data are generated during transmission of the first data, punctures a portion in which a predetermined signal is transmitted in a resource allocated for the transmission of the first data, transmits the first data in an unpunctured portion, and transmits the second data in the punctured portion.

Abstract: A user equipment in a radio communication system including a base station and the user equipment, the user equipment including: a resource management unit that retains configuration information of a resource capable of transmitting uplink data without receiving uplink data transmission permission from the base station; and a transmission unit that transmits a signal indicating that uplink data transmission using the resource is performed to the base station.

Abstract: The present invention is designed to adequately control resource regions for contention-based UL transmission. A user terminal, according to the present invention, has a transmission section that transmits UL data without an uplink (UL) grant from a radio base station, and a control section that controls transmission of the UL data, and the control section configures a plurality of resource regions with varying parameters, and selects a resource region to use to transmit the UL data from among the plurality of resource regions.

Abstract: Provided is a user equipment in a radio communication system that includes a plurality of user equipments and a base station and supports a communication scheme in which uplink radio resources are shared by the plurality of user equipments, and the user equipment includes a control unit that determines that retransmission of an uplink signal is performed when NACK is received from the base station with respect to the uplink signal or when none of ACK and NACK are received with respect to the uplink signal and a transmitting unit that retransmits the uplink signal on the basis of a predetermined retransmission scheme when the control unit determines that the retransmission of the uplink signal is performed.

Abstract: Provided is a technique that transmits data, which is transmitted without obtaining transmission permission, with low delay and high reliability. An aspect of the invention relates to a transmitter including a resource determination unit that determines whether a first type of resource has been allocated in response to the generation of a transmission event for a predetermined type of information and a transmitting unit that transmits the predetermined type of information to a receiver, using the first type of resource, without obtaining transmission permission, when the first type of resource has been allocated.

Abstract: The present invention is designed to reduce the impact of communication using TTIs with different numbers of symbols (or different numbers of REs) on the throughput of data channels. A transmitting/receiving section that transmits and receives signals using a plurality of transmission time intervals (TTIs) with different numbers of symbols, and a control section that controls the transmission and receipt of the signals by applying a predetermined transport block size (TBS) in each TTI are provided, where the predetermined TBS in each TTI is controlled according to the number of symbols in each TTI or a target coding rate that is configured in advance.

Abstract: A user equipment used in a radio communication system, including: a receiving unit that receives, from a base station, a part of pieces of control information used for acquiring a desired signal from a multiplexed signal obtained by multiplexing signals of a plurality of users in a power region; and a desired signal acquiring unit that acquires the desired signal from the multiplexed signal using the control information, wherein when the receiving unit receives the part of pieces of control information from the base station, the desired signal acquiring unit uses information the same as information of the desired signal as information of interference signal which is not received from the base station among the control information.

Abstract: A user equipment in a mobile communication system including a base station and the user equipment, including: a mode determining unit that receives instruction information indicating a transmission mode of broadcast information from the base station and determines the transmission mode based on the instruction information; and a receiving unit that performs a reception operation of the broadcast information according to the transmission mode determined by the mode determining unit.

Abstract: The present invention is designed to reduce the latency due to collisions in UL transmission when contention-based UL data transmission is employed. A user terminal communicates using a second transmission time interval (TTI), having a shorter TTI duration than a first TTI, and this user terminal has a transmission section that transmits multiple UL data without a UL grant from a radio base station, and a control section that controls allocation of the multiple UL data individually, and the control section applies frequency hopping to allocate the multiple UL data to resources of different second TTIs.

Abstract: The present invention is designed to reduce the time it takes to form adequate beams, in communication using beamforming. According to one aspect of the present invention, a user terminal has a transmission section that, using temporally orthogonal radio resources, forms different transmitting beams and transmits reference signals respectively to a radio base station, and a control section that controls the forming of the transmitting beams so that at least one of the reference signals is received in a receiving beam which the radio base station forms in a given period set.

Abstract: The present invention is designed to reduce the time it takes to form adequate beams, in communication using beamforming. According to one aspect of the present invention, a user terminal has a receiving section that, using temporally orthogonal radio resources, forms receiving beams and receives reference signals that are transmitted in different transmitting beams respectively, a measurement section that performs measurements based on the reference signals, and a control section that controls the forming of the receiving beams so that at least one of the reference signal is received in a given period set.

Abstract: The present invention is designed to reduce the impact which the variation of the amount of overhead within a subframe has upon the throughput of data channels. A user terminal, according to the present invention, has a transmitting/receiving section that receives a downlink (DL) signal and/or transmits an uplink (UL) signal in a subframe, and a control section that controls transport block sizes (TBSs) of the DL signal and/or the UL signal. The user terminal controls the TBSs based on overhead in the subframe or a desired coding rate.

Abstract: A user equipment that is provided in a wireless communication system including a base station and the user equipment includes a selection unit that selects one access method from a plurality of access methods used when uplink communications start and a communication unit that transmits an uplink signal to the base station according to a procedure defined by the selected access method.

Abstract: A base station used in a radio communication system includes a precoding matrix calculating unit that calculates a precoding matrix based on a first precoding matrix reported from a first user equipment in a pair selected as a target of multiplexing in a power region and a second precoding matrix reported from a second user equipment in the pair and a precoding unit that applies a precoding to transmission signals to the first user equipment and the second user equipment using the precoding matrix calculated by the precoding matrix calculating unit.

Abstract: A base station, according to received qualities at user devices, allocates a downlink transmission power to each user device. The base station transmits a mixed data signal in which data signals mutually not orthogonal and each addressed to a corresponding user device are mixed. Control signals are transmitted to user devices to enable each user device to decode a data signal addressed to the user device using a control signal corresponding to the user device. Each control signal is scrambled by the identifier of the corresponding user device. A control signal for a first user device to which a first data signal is addressed includes information indicating the identifier of a second user device to which a second data signal mixed with the first data signal is addressed. The first user device is thus enabled to descramble a control signal for the second user device.

Abstract: To suppress decrease in throughput even in the case of combining NOMA and MIMO to use, a radio base station according to one aspect of the present invention has a transmission section that transmits a DL signal to each of a plurality of user terminals with a single or a plurality of streams, and a control section that controls so as to perform power multiplexing on DL signals transmitted to the user terminals to transmit, where the control section sets a multiplexing power ratio of the DL signals to perform power multiplexing for each stream.

Abstract: To enable communication to be performed with a communication scheme suitable for the future radio communication system where a plurality of user terminals is multiplexed in the power domain, a user terminal of the present invention is provided with a reception section that receives a downlink (DL) signal to the user terminal, and a decoding section that decodes the DL signal to the user terminal, where at least one of a cyclic prefix (CP) length, symbol length and transmission time interval (TTI) length is different between the DL signal to the user terminal and a DL signal to another user terminal multiplexed in the power domain.

Abstract: A user apparatus in a radio communication system that includes a base station and the user apparatus is provided. The user apparatus includes: a transmitter that reports, to the base station, antenna count information that indicates a number of reception antennas supported by the user apparatus; a first receiver that receives, from the base station, indication information that indicates a number of reception antennas to be activated in the user apparatus; and a second receiver that receives, in in response to the first receiver receiving the indication information, downlink signals from the base station using the number of reception antennas to be activated in the user apparatus.

Abstract: A base station allocates downlink transmission powers to user equipments according to the reception qualities of the user equipments. The base station transmits a mixed data signal in which multiple data signals that are addressed to multiple user equipments and are not orthogonal to each other are mixed, and transmits multiple control signals to the multiple user equipments such that each user equipment can decode the data signal addressed to that user equipment using the control signal corresponding to that user equipment. Each control signal is scrambled using the identifier of the user equipment corresponding to that control signal. With a period longer than the transmission period for the control signal, the base station notifies the multiple user equipments of identifier information indicating multiple identifiers, and thus the user equipment can descramble a control signal for another user equipment to which an interference data signal with a higher transmission power is addressed.

Abstract: From a base station, a user equipment receives a mixed data signal transmitted in a format in which multiple data signals are transmitted with different downlink transmission powers such that the multiple data signals are not orthogonal to each other, multiple control signals corresponding to multiple user equipments, and information indicating an identifier of another user equipment. The user equipment determines an aggregation level of the subject user equipment. The user equipment uses the identifier of the other user equipment to attempt descrambling of one control signal among multiple control signals corresponding to an aggregation level higher than or equal to the aggregation level of the user equipment, and if the descrambling is successful, the user equipment uses the control signal to demodulate the non-orthogonal data signal.