Abstract: A radio terminal according to one embodiment comprises a controller configured to transmit a physical uplink shared channel to a base station by an interlace mapping using a plurality of resource blocks distributed on a frequency axis while overlapping on a time axis. The controller receives, from the base station, control channel information on a time-frequency resource used for transmitting the physical uplink control channel. The controller stops transmission in a specific resource block corresponding to the time-frequency resource from among the plurality of resource blocks, based on the control channel information.

Abstract: A radio terminal according to one embodiment comprises: a controller configured to perform a process of: receiving, if the radio terminal is in a specific state different from an RRC connected state, multicast/broadcast data transmitted from a base station; and transmitting feedback information on the multicast/broadcast data to the base station. The controller is configured to autonomously determine a transmission parameter to be used for transmitting the feedback information and transmits the feedback information by using the determined transmission parameter.

Abstract: A user equipment, apparatus and method comprise starting reception from a base station from a second slot out of a first slot and the second slot which configure a subframe, determining a first modulation order used for downlink control information transmitted in the second slot, and starting the reception from the second slot by using the first modulation order. The downlink control information is a PDCCH or an EPDCCH.

Abstract: A user terminal, a base station, and method include a user terminal performing D2D communication under management of a base station, the D2D communication indicating direct device to device communication including transmitting data to one or more D2D communication destinations in the D2D communication and transmitting a D2D buffer status report to the base station. The user terminal transmits to the base station a D2D buffer status report indicating an amount of non-transmitted data in the D2D communication and a plurality of identifiers corresponding to the one or more D2D communication destinations. The plurality of identifiers corresponding to the one or more D2D communication destinations does not include the identifier of the base station to which the D2D buffer status report is transmitted.

Abstract: When a UE 100-2 (a reception-side UE) that performs D2D communication by using UL radio resource switches communication modes between cellular communication and the D2D communication, if DL subframe in which data reception of the cellular communication should be performed and the UL subframe in which data reception of the D2D communication should be performed at least partially overlap on a time axis, then the UE 100-2 performs data reception in one subframe, out of the overlapping two subframes.

Abstract: A communication control method, user equipment and apparatus thereof include transmitting, to a base station by a user equipment, first information on a priority of a data pack to be transmitted from the user equipment via direct communication in which the data packet is transmitted to another user equipment without passing through the base station. The first information assists the base station in scheduling transmission resources for the direct communication. The method, user equipment and apparatus also include transmitting a request for requesting transmission resources for the direct communication to the base station by the user equipment, and receiving by the user equipment from the base station second information indicating transmission resources for the direct communication scheduled by the base station.

Abstract: A communication method according to an embodiment includes transmitting first information for causing a user terminal to hold context information of the user terminal from a network to the user terminal in a radio resource control (RRC) connected state. The context information includes a cell-radio network temporary identifier (C-RNTI) allocated to the user terminal. The user terminal holds the context information without discarding the context information, based on the first information, even if the user terminal transitions from the RRC connected state.

Abstract: A first radio terminal transmits and receives a radio signal by using a limited frequency band limited to a bandwidth of a predetermined number of resource blocks. A second radio terminal transmits and receives a radio signal by using a frequency band wider than the limited frequency band. A base station transmits configuration information of SC-MTCH by SC-MCCH. The base station sets a first period to the first radio terminal and sets a second period shorter than the first period to the second radio terminal as an SC-MCCH change period in which the configuration information of the SC-MTCH can be changed. The base station receives an MBMS interest indication from the first radio terminal, the first radio terminal being in a connected mode, and determines whether or not to shift the first radio terminal to an idle mode based on the MBMS interest indication.

Abstract: A mobile communication method for performing predetermined communication between a base station and a user terminal by using a narrow band including 6 resource blocks comprises: transmitting, from the base station to the user terminal, narrow band allocation information allocating a predetermined number of the narrow bands to the user terminal as allocation information of the narrow band used for the predetermined communication; performing by the user terminal, the predetermined communication by using the predetermined number of narrow bands based on the narrow band allocation information; transmitting, from the base station to the user terminal, an RRC message including information specifying a bandwidth supportable by the user terminal; and changing, by the base station, a number of bits of the narrow band allocation information according to the bandwidth supportable by the user terminal. The predetermined number of narrow bands are provided within a bandwidth supportable by the user terminal.

Abstract: A base station 100 in a radio transmission system that performs multicast/broadcast transmission comprises a multiplexing unit 110 configured to multiplex a plurality of types of transmission data transmitted in schemes different in error tolerance; and a transmitter 120 configured to transmit multiplexed data obtained by the multiplexing unit 110, by multicast/broadcast. The plurality of types of transmission data includes basic transmission data transmitted, by the transmitter, in a scheme having a first error tolerance and additional transmission data transmitted, by the transmitter, in a scheme having a second error tolerance lower than the first error tolerance. The additional transmission data is utilized in a terminal 200 by being combined with the basic transmission data.

Abstract: A communication control method is a method for performing offload to transfer a traffic load of a cellular base station to an access point. The communication control method comprises a step of maintaining without releasing the first connection, by a user terminal that have established a first connection with the cellular base station, even when the offload is started after establishing a second connection with the access point; and a determining step of determining, by the user terminal, whether the offload is continued or canceled after the offload is started.

Abstract: A communication apparatus comprises: a first processing unit configured to perform processing of a first layer; and a second processing unit configured to perform processing of a second layer which is provided to be upper than the first layer. The second processing unit is configured to perform communication by using a first component carrier included in a licensed band and perform communication by using a second component carrier included in an unlicensed band. The first processing unit is configured to perform communication by using the first component carrier and performs communication by using an element carrier selected from among a plurality of element carriers associated with the second component carrier.

Abstract: A network apparatus according to an embodiment performs communication with a user terminal comprising a first communication unit configured to perform communication using a first radio access technology and a second communication unit configured to perform communication using a second radio access technology, by using the first access technology. The network apparatus comprises: a receiver configured to receive, from the user terminal, authentication related information on a country where the user terminal is legally authenticated for transmission by the second communication unit; and a controller configured to determine, based on the authentication related information, whether or not communication by the second communication unit can be configured to the user terminal.

Abstract: A method applied to a mobile communication system including a first communication apparatus, a first communication apparatus, and chipset included in a first communication apparatus, where the communication apparatus performs relay transmission between a network and a second communication apparatus, includes obtaining, by the first communication apparatus, information indicating a function supported by a network apparatus included in the network, and transmitting to the network apparatus, by the first communication apparatus based on the information, a request message for performing the relay transmission.

Abstract: A base station according to an embodiment is a base station configured to perform transmission to a user terminal by use of an unlicensed band. The base station comprises: a controller configured to start the transmission from a boundary of a subframe, but also to start the data transmission from a second-half slot out of a first-half slot and the second-half slot which configure a subframe. The controller is configured to transmit downlink control information in the second-half slot to start the transmission from the second-half slot. The controller is configured to change a modulation scheme to be applied to the transmission, depending on a start timing of the transmission, while fixing a transport block size applied to the subframe. The downlink control information is a PDCCH or an EPDCCH.

Abstract: A user equipment for a mobile communication system, and method and chip thereof, receives a first parameter and a second parameter broadcasted from the current serving cell, and reselects a target cell to be used as a serving cell from among plural cells operated at different frequencies. The first parameter defines a probability for performing reselection of the target cell, and the second parameter is a timer value to be set in a timer started at a timing at which a quality measurement for neighbor cells ends. Reselecting includes, after receiving the first and second parameter, periodically measuring qualities of neighbor cells at timer defined timings, comparing a value corresponding to IMSI of the user equipment with a value corresponding to the first parameter, and reselecting the target cell from among cells having a quality satisfying predetermined quality criteria, based on results of the quality measurement and the comparison.

Abstract: A mobile communication method according to an embodiment includes a step in which a base station configured to perform communication by using a narrow band which is a second bandwidth narrower than a first bandwidth compatible with a first user terminal in one unit time transmits information for allocating a second user terminal an extended band having a third bandwidth wider than the second bandwidth and narrower than the first bandwidth in the one unit time.

Abstract: A base station and method thereof includes transmitting from the base station to a user equipment, parameters for an offload from the cellular RAN to a wireless local area network (LAN). The parameters are used by the user equipment to perform an access network selection between the cellular RAN and the wireless LAN, and include a first threshold for comparison with a cellular signal strength of the cellular RAN, a second threshold for comparison with a wireless LAN signal strength of the wireless LAN, and a third threshold for comparison with a load of the wireless LAN. When performing access network selection, the parameters may cause the user equipment to perform the offload, in response to the cellular signal strength being lower than the first threshold, the wireless LAN signal strength being higher than the second threshold, and the load of the wireless LAN being lower than the third threshold.

Abstract: A mobile communication system includes a user terminal that performs D2D communication under management of a base station, the D2D communication indicating direct device to device communication. The user terminal transmits a D2D buffer status report indicating an amount of non-transmitted data in the D2D communication to the base station.

Abstract: A radio terminal performs radio communication with a base station in a mobile communication system. The radio terminal includes a controller configured to perform processing of transmitting an aperiodic CSI feedback related to a downlink channel state to the base station. In response to a predetermined condition being satisfied, the controller performs multiplex transmission in which uplink data in which the aperiodic CSI feedback is multiplexed is transmitted to the base station, by using a PUSCH resource.