Abstract: The present invention is designed to improve spectral efficiency in a radio communication system which can use non-orthogonal multiple access (NOMA). Steps are provided in which a radio base station configures one of a plurality of transmission mode including a first transmission mode, which groups a plurality of transmission methods including a transmission method to employ non-orthogonal multiple access (NOMA) and multiple-user multiple-input and multiple-output (MU-MIMO), and a second transmission mode, which groups a plurality of transmission methods including a transmission method to employ this NOMA and open-loop transmit diversity, and transmits a downlink signal for this user terminal based on the configured transmission mode.

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: The present invention is designed so that adequate communication can be carried out even in future radio communication systems. A user terminal communicates using a transmission time interval (TTI), which has a predetermined TTI duration, and has a receiving section that receives a DL signal, a transmission section that transmits a UL signal, and a control section that controls at least one of transmission of a random access preamble, transmission of an SRS, reception of a broadcast channel and reception of a mobility reference signal, based on downlink control information that is included in the same TTI.

Abstract: This invention aims to achieve appropriate communication even when a radio frame configuration which may involve short-time feedback is used. In an aspect of this invention, provided is a user terminal in a system which performs communication based on a TTI (Transmission Time Interval) length, the equipment including a transmission and reception unit which transmits and/or receives capability information concerning a supportable delay, and a control unit which performs control to receive a certain downlink radio resource and/or transmit a certain uplink radio resource at a time interval equal to or greater than the delay.

Abstract: A user apparatus configured to communicate with a base station in a radio communication system including a base station and the user apparatus, including: first reference signal reception means configured to measure a received power of first reference signals, transmitted from the base station, that are associated with a plurality of different identifiers, and to select a specific first reference signal; report means configured to report an identifier and a received power of the first reference signal selected by the first reference signal reception means to the base station or a macro cell base station; second reference signal reception means configured to receive a plurality of second reference signals transmitted from the base station; and measurement means configured to measure a reception quality of the second reference signals received by the second reference signal reception means, and to transmit feedback information based on the reception quality to the base station.

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: To appropriately prevent interference, even when UL or DL is controlled in a dynamic manner, a user terminal for performing communication using a transmission time interval (TTI) having a certain TTI length includes a measurement unit for performing measurement using a measurement resource dynamically assigned by a radio base station, and a transmission unit for transmitting information related to a measurement result. The measurement unit performs measurement of a signal transmitted from another user terminal using the measurement resource.

Abstract: A radio base station that communicates with a user terminal, and has a control section that executes control so that signals are time-division-multiplexed over a first radio resource region where symbols are multiplexed at a rate equal to or below a Nyquist rate and a second radio resource region where symbols are multiplexed at a faster rate than the Nyquist rate. The radio base station also includes a transmission section that transmits the signals that are time-division-multiplexed in the first radio resource region and the second radio resource region, to the user terminal to reduce the interference against predetermined signals in a radio communication system in which Faster-Than-Nyquist (FTN) is used.

Abstract: User equipment for communicating with a base station in a radio communication system supporting communication based on a TDD scheme, the user equipment including a transmitter that transmits an uplink signal while setting a guard time in the uplink signal based on a report signal indicating a structure for each subframe, the report signal being transmitted from the base station; a receiver that receives a downlink signal from the base station; and an identification unit that identifies, based on the report signal, a position of a guard time that is set in the downlink signal received by the receiver.

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 mobile communications system having a first base station and one or more second base stations is disclosed, wherein the first base station includes a first generator which generates a first known signal for use in common between the first base station and the second base station and a second known signal use specific to each of the first base station and the second base station, and a radio transmitter which wirelessly transmits, to a subordinate terminal apparatus, the first known signal and the second known signal which are generated by the first generator.

Abstract: A radio base station applies non-orthogonal multiple access to a plurality of user terminals and transmits downlink signals, and this radio base station has a scheduling section that selects a user set to apply non-orthogonal multiple access to from candidate user sets, and selects a combination of a modulation and coding scheme and transmission power based on combinations of candidate transmission power. The radio base station includes a control section that decides whether or not the combination of the modulation and coding scheme and transmission power selected in the scheduling section is included in combinations that are stipulated in advance, and controls the scheduling section in accordance with the decision. A transmission section applies the combination of the modulation and coding scheme and transmission power to user terminals that are included in the user set selected in the scheduling section, and transmits the downlink signals.

Abstract: A user device communicates with base stations in a radio communication system including the base stations. The user device includes a receiver that receives a first downlink control signal transmitted from one of the base stations, a transmitter that transmits uplink signals using multiple antenna ports or multiple beams, and a controller that controls, for each subframe, transmission timing of the uplink signals transmitted using the multiple antenna ports or the multiple beams, based on the first downlink control signal.

Abstract: A user terminal includes a receiver that receives, from a radio base station, indication information to indicate whether or not uplink signals of a plurality of user terminals are non-orthogonal-multiplexed; a processor that switches between transmission power control methods based on the indication information; and a transmitter that transmits an uplink signal by using a switched transmission power control method.

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: To enable a mobile terminal apparatus to correctly demodulate a data signal in the case of applying Coordinated Multi-Point transmission (CoMP), particularly, JP-CoMP, a radio communication method of the invention is characterized in that a radio base station apparatus generates information for demodulation of a data signal in a mobile terminal apparatus in applying Coordinated Multi-Point transmission, and transmits the information for demodulation to a mobile terminal apparatus that performs Coordinated Multi-Point reception, and that the mobile terminal apparatus receives the information for demodulation of a data signal, and demodulates the data signal subjected to Coordinated Multi-Point reception using the information for demodulation.

Abstract: To provide a user terminal, radio base station apparatus, radio communication system and radio communication method that support increases in the number of users, a user terminal is provided with a reception section that receives a downlink control signal multiplexed into radio resources from the starting OFDM symbol to a predetermined OFDM symbol in a subframe, and a downlink control signal subjected to frequency division multiplexing with a downlink data signal into radio resources after the predetermined OFDM symbol, a retransmission check section that performs a retransmission check on the downlink data signal based on the downlink control signal subjected to frequency division multiplexing to output a retransmission response signal, and a selection section that selects a radio resource of an uplink control channel used in transmission of the retransmission response signal.

Abstract: The present invention is designed to provide a wireless communication system, a base station apparatus, a user terminal, and a channel state information measurement method that can allow a user terminal to feed back channel quality information that is optimal for a transmission mode from a plurality of transmission points.

Abstract: To provide a radio communication method for enabling a control signal to be received with high quality and high efficiency, in the case of using spatial multiplexing transmission in data signals to transmit, and also transmitting the control signal in the same sub-frame, in the radio communication method of the invention, a mobile terminal apparatus receives a downlink signal including precoding information, separates a data signal and a control signal to assign to different radio resources, and performs MIMO-transmission on a signal of each transmission layer based on the precoding information, and a radio base station apparatus receives an uplink signal including the data signal and the control signal subjected to MIMO transmission, divides the uplink signal into data signals for each transmission layer, and reproduces the control signal from the uplink signal.

Abstract: Provided are a radio communication system, a base station, a mobile station, and a radio communication method, by which it is possible to shorten a control time until the transmission of uplink data is possible, and to improve a perceived speed of a user when uplink data is small. A base station 100 transmits collision-type access permission including information on a collision-type access channel toward a plurality of mobile stations, the collision-type access channel serving as a radio resource other than a radio resource assigned in response to a scheduling request and a radio resource available for transmission of uplink data by the plurality of mobile stations. A mobile station 200A transmits the uplink data to the base station by using the collision-type access channel on the basis of the collision-type access permission received from the base station.