Abstract: The present invention is designed to realize appropriate communication in next generation communication systems. a control section that controls communication by using a radio frame that includes a plurality of transmission time intervals (TTIs), in which the downlink and the uplink can be switched, and a given TTI, which is for DL transmission and which is configured in a given cycle, and a receiving section that receives a synchronization signal and a broadcast signal in the given TTI are provided.

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: A user apparatus is provided. The user apparatus performs communications with a base station. The user apparatus includes a receiving unit configured to receive a downlink pilot signal, a downlink control signal, and downlink user data by using a subframe that includes a pilot signal area, to which the downlink pilot signal is mapped, a control signal area, to which the downlink control signal is mapped, a user data area, to which the downlink user data is mapped, and a multiple use area, to which an uplink signal or a downlink signal is mapped; and a transmission unit configured to map the uplink signal to the multiple use area and transmit the mapped result to the base station in the case where information is included in the downlink control signal indicating that the uplink signal is to be mapped to the multiple use area.

Abstract: A radio communication system includes a first radio base station having multiple antenna elements, and user equipment, wherein, for initial connection of the user equipment to the first radio base station, the first radio base station applies different precoding vectors to a downlink user common signal transmitted to all users located in or near a serving area of the first radio base station, and transmits the downlink user common signal while changing the applied precoding vector; wherein the user equipment selects a desired one of the precoding vectors applied to the downlink user common signal, and reports a selection result to the first radio base station, and wherein the first radio base station precodes a data signal addressed to the user equipment using the selected precoding vector and transmits the precoded data signal to the user equipment.

Abstract: A terminal is disclosed that includes a receiver that receives higher layer signaling that indicates a periodic time period in which uplink transmission is not performed and a processor that monitors downlink control information for scheduling system information in the time period. In other aspects, a radio communication method and a base station are disclosed.

Abstract: The present invention is designed to communicate using a radio interface with improved scalability in the frequency domain. According to the present invention, a user terminal includes a receiving section that receives a downlink control signal including information about the assignment of a downlink data signal and receives the downlink data signal based on the downlink control signal, and a transmission section that transmits an uplink control signal including transmission acknowledgment information in response to the downlink data signal. Further, a plurality of frequency domain units constituting the entire frequency band as a block are formed. The downlink control signal, the downlink data signal and the uplink control signal are time-division-multiplexed in the same frequency domain unit.

Abstract: In user equipment for communicating with a base station in a radio communication system including the base station and the user equipment, the user equipment includes a receiver that measures received power of reference signals associated with a plurality of different identification information items, the reference signals being transmitted from the base station, and that selects a specific reference signal based on a measurement result; and a transmitter that transmits a random access signal including a preamble sequence, the preamble sequence corresponding to the identification information item of the reference signal selected by the receiver.

Abstract: A radio communication method for a user terminal performing communication in a cell where DL transmission and UL transmission vary in a time direction is provided. The radio communication method includes receiving downlink control information transmitted in a specific subframe; and analyzing a number and/or positions of subframes to be allocated for the DL transmission among subframes constituting a radio frame based on DL assignment in the downlink control information.

Abstract: To perform appropriate AMC control even if low latency is required. A transmission apparatus includes: a reception section that receives channel quality information communicated between the transmission apparatus and a reception apparatus; a control section that determines one or more first candidates for a value indicating a coding and modulation scheme based on the channel quality information, determines one or more second candidates for a value indicating the coding and modulation scheme based on a parameter related to service quality required for a service communicated between the transmission apparatus and the reception apparatus, and selects a value included in both of the first candidates and the second candidates; and a transmission section that transmits transmission data using the coding and modulation scheme corresponding to the selected value.

Abstract: Provided are a receiver, a transmitter and a radio communication method capable of using non-orthogonal multiple access while suppressing cost increase and processing delay. A mobile station 200A includes a target user control signal detector 230 and an interfering user control signal detector 240 which are configured to receive a control signal to be used to cancel a non-orthogonal signal by interference canceller. The control signal includes control information containing a radio resource block allocated to the non-orthogonal signal addressed to another mobile station. The mobile station 200A demodulates and cancels the radio signal addressed to the other mobile station on the basis of the control signal.

Abstract: It is one of the objects to achieve an appropriate communication in a next generation communication system. The user terminal according to one aspect of the present invention includes a receiving section that receives a synchronization signal and a transmitting section that uses a sequence and/or a radio resource determined based on the synchronization signal to transmit a random access preamble.

Abstract: The present invention is designed to allow adequate communication in a next generation communication system in which a plurality of numerologies are introduced. A control section that controls communication using at least one of a plurality of numerologies with different subcarrier spacings, and a receiving section that receives information related to numerology for use in communication are provided, and the plurality of numerologies with different subcarrier spacings are configured that one of the length of a transmission time interval (TTI) and the number of symbols per TTI is different.

Abstract: A base station for transmitting a synchronization signal from N transmission antennas (N>=2) in orthogonal frequency division multiple access includes a signal sequence generation unit configured to generate a synchronization signal sequence to be used for the synchronization signal in a frequency domain; a subcarrier mapping unit configured to divide a transmission band of the synchronization signal into K frequency blocks (K>=2) and map the synchronization signal sequence into one or more subcarriers in the K frequency blocks; a precoding unit configured to generate N precoding vectors to be multiplied by the synchronization signal sequence in the frequency domain and multiply the synchronization signal sequence to be transmitted from an n-th antenna (1<=n<=N) by at least an n-th precoding vector; and a transmission unit configured to transmit the synchronization signal from the N transmission antennas.

Abstract: A radio base station making it possible to perform efficient scheduling of user terminals by reducing feedback information to be received from the user terminals is provided. A radio base station includes a position-related-information obtaining section configured to obtain position-related information indicating positional relationships among multiple user terminals. In addition, the radio base station includes a scheduler configured to determine user groups of the user terminals to be spatially multiplexed in the same time and frequency resources based on the position-related information obtained by the position-related-information obtaining section.

Abstract: To perform appropriate AMC control even if low latency is required. A transmission apparatus includes: a reception section that receives channel quality information communicated between the transmission apparatus and a reception apparatus; a control section that determines one or more first candidates for a value indicating a coding and modulation scheme based on the channel quality information, determines one or more second candidates for a value indicating the coding and modulation scheme based on a parameter related to service quality required for a service communicated between the transmission apparatus and the reception apparatus, and selects a value included in both of the first candidates and the second candidates; and a transmission section that transmits transmission data using the coding and modulation scheme corresponding to the selected value.

Abstract: A user apparatus is disclosed herein that includes a receiver configured to receive a plurality of synchronization signals and a transmitter configured to transmit a sounding reference signal associated with a specific synchronization signal of the plurality of synchronization signals. The transmitter also maps the sounding reference signal to consecutive OFDM symbols in one slot.

Abstract: A radio base station making it possible to perform efficient scheduling of user terminals by reducing feedback information to be received from the user terminals is provided. A radio base station includes a position-related-information obtaining section configured to obtain position-related information indicating positional relationships among multiple user terminals. In addition, the radio base station includes a scheduler configured to determine user groups of the user terminals to be spatially multiplexed in the same time and frequency resources based on the position-related information obtained by the position-related-information obtaining section.

Abstract: A user apparatus communicating with a base station in a radio communication system including the base station and the user apparatus includes a first receiving unit to receive multiple first reference signals transmitted from the base station; a detection unit to detect a specific antenna port via which the plurality of first reference signals is received, or a specific directivity pattern, among a plurality of directivity patterns generated by a plurality of antenna ports, in which the plurality of first reference signals are received; a measuring unit to measure reception power of each of the first reference signals; and a transmission unit to group the reception power of each of the first reference signals into one of groups of the specific antenna port and the specific directivity pattern via which the first reference signals are received to transmit the groups of the reception power to the base station.

Abstract: The object is achieved by providing a base station apparatus for performing time and frequency scheduling in uplink packet access with: an interference amount measurement part configured to measure an uplink interference amount for each interference amount measurement unit which comprises a predetermined period and a predetermined number of frequency blocks; an interference amount determination part configured to determine whether the uplink interference amount satisfies a predetermined condition; and an overload indicator reporting part configured to report an overload indicator to a neighboring cell when the predetermined condition is satisfied.

Abstract: To provide a radio base station apparatus and radio communication method capable of performing radio communications using downlink reference signal structures suitable for antenna virtualization, a radio base station apparatus (200) has a plurality of transmission antennas, generates CRSs used in demodulation of at least downlink control information, CQI-RSs generated for each of the transmission antennas used in measurement of channel quality, and DM-RSs generated for each stream used in demodulation of downlink transmission data, and multiplexes the CRSs, CQI-RSs and DM-RSs into a same transmission time unit to transmit from each of the antennas.