Abstract: A base station used as a first base station in a radio communication system including the first base station, a second base station communicating via the first base station with a user device, and the user device communicating with the first base station. The base station includes a first receiver that receives an uplink signal transmitted from the user device; a measurer that measures a timing difference between a timing of receiving the uplink signal and a predetermined reference timing retained by the base station; and a first transmitter that transmits, to the user device, a command that is generated based on the timing difference and used to control a transmission timing at which the user device transmits the uplink signal.

Abstract: A base station according to an embodiment is provided. The base station communicates with a user apparatus in an LTE-supported wireless communication system. The base station includes a generation unit configured to generate a signal in which a UE specific reference signal is mapped according to a first pattern in which, in a range of resource elements enclosed by a segment in the time direction indicated by a predetermined subframe in which a synchronization signal is mapped and by a segment in the frequency direction in which the synchronization signal is mapped, a UE specific reference signal is mapped onto a resource element other than a resource element onto which the synchronization signal is mapped; and a transmission unit configured to transmit the generated signal.

Abstract: There is provided a user apparatus of a radio communication system, the user apparatus including a speed measuring unit configured to measure a moving speed of the user apparatus; and a quality measuring unit configured to detect a cell or to measure reception quality of the cell in accordance with a measurement condition corresponding to the measured moving speed of the user apparatus, based on the measurement condition permitted for detecting the cell or permitted for measuring the reception quality of the cell, the measurement condition being defined depending on the moving speed of the user apparatus, and based on the moving speed of the user apparatus measured by the speed measuring unit.

Abstract: A user terminal includes a receiver that receives a downlink shared channel and a processor that obtains a transport block size (TBS) used for the downlink shared channel based on: a TBS index value that is associated with a modulation and coding scheme (MCS) index value used for the downlink shared channel; and a number of resource blocks (RBs) that are allocated to the downlink shared channel. When the downlink shared channel is transmitted by a predetermined transmission scheme and the MCS index value is a predetermined value, the processor modifies the TBS index value associated with the predetermined value and obtains the TBS based on the modified TBS index value and the number of RBs.

Abstract: A user apparatus in a mobile communication system including a first base station that sets a link of a control plane between the first base station and the user apparatus, and a second base station that sets a link of a user plane between the second base station and the user apparatus, including: radio link monitoring means configured to perform monitoring of a radio link; and connection control means configured, when disconnection of the link of the control plane is detected by the radio link monitoring means, to perform reestablishment of the link of the control plane for the user apparatus while maintaining the link of the user plane.

Abstract: An object is to improve the throughput of a mobile station UE without affecting the coverage of a macrocell in a case where CA is introduced to a HetNet environment. A radio base station eNB according to the present invention is configured to determine whether or not to change the connection destination of a mobile station UE from a small cell #1 to a small cell #2 while the mobile station UE is performing CA by using the macrocell and the small cell #1, based on at least one of the congestion status in each of the small cell #1 and the small cell #2 and the communication quality in each of the small cell #1 and the small cell #2.

Abstract: A system and method to prevent collision between mobile stations to which the same C-RNTI is allocated in a simple implementation while avoiding a problem of C-RNTI depletion in a phantom cell is disclosed. A radio base station includes an allocation unit configured to allocate multiple C-RNTIs to each of mobile stations, and the allocation unit performs adjustment such that collision of search spaces to which PDCCH resources are allocated does not occur among the multiple mobile stations.

Abstract: To improve probability of successfully performing origination processing by a priority terminal and origination processing of an emergency call even during congestion. In a mobile station UE according to the present invention, an AS function unit 11 is configured to receive SSAC information from a radio base station eNB and transmit the SSAC information to the NAS function unit 12 at a predetermined timing, and a NAS function unit 12 is configured to perform SSAC on transmission of “RA Preamble” in a RA procedure for the mobile station UE in the DRX state to transmit an uplink signal, or on transmission of an uplink signal from the mobile station UE in the Non-DRX state.

Abstract: A base station is provided. The base station is used as a first base station in a mobile communication system including the first base station, a second base station communicating with the first base station, and a user apparatus communicating with the first base station. The base station includes a first reception unit configured to receive from the second base station a process ID used for error correction processing; a second reception unit configured to receive data from the user apparatus; and a transmission unit configured to transmit the data and the process ID to the second base station in the case where the data is received from the user apparatus.

Abstract: The present invention is designed to provide highly efficient small cell radio access. In a communication system to include a macro station (30), a local station (20), and a mobile terminal apparatus (10), the local station (20) generates measurement signals that are used in measurements in the mobile terminal apparatus (10) based on user an identifier or a user group identifier, and transmits this signal to the mobile terminal apparatus (10). The mobile terminal apparatus (10) receives the measurement signals transmitted from the local station (20) and carries out with measurements with respect to the measurement signals based on the user identifier or the user group identifier.

Abstract: A user apparatus which performs communications with one or more base stations in a communication system which supports carrier aggregation is provided. The user apparatus includes a control unit configured to select a specific cell or a specific cell group as a reference of an uplink transmission carrier switching timing, from a plurality of cells or a plurality of cell groups with which the carrier aggregation is configured; and a transmission unit configured to perform switching from uplink transmission using a first cell carrier to uplink transmission using a second cell carrier based on a transient period timing in the selected specific cell or specific cell group.

Abstract: A user apparatus is provided. The user apparatus is included in a mobile communication system including a first base station, a second base station communicating with the first base station, and the user apparatus communicating with the first base station. The user apparatus includes an obtaining unit configured to obtain from the second base station instruction information indicating an error correction processing operation performed between the first base station and the user apparatus; and a communication unit configured to communicate with the first base station by performing the error correction processing based on the instruction information.

Abstract: The present invention is designed to apply beam forming control between base stations in accordance with traffic that varies over time or geographically. A radio base station can exchange control information with a neighbor radio base station via backhaul, and has a transmitting/receiving section that transmits and receives the control information through backhaul signaling, and a control section that controls the antenna beam pattern of one or both of the neighbor radio base station and the radio base station based on traffic information and information about antenna beam forming for the neighbor radio base station and the radio base station, which are included in the control information.

Abstract: The present invention aims to reduce an insertion loss or the like caused by a diplexer inserted to reduce leakage from an uplink bandwidth to a downlink bandwidth of different bands, and thereby to improve a communication quality. A mobile communication method according to the present invention includes the steps of: transmitting simultaneous transmission capability information from a mobile station UE to a radio base station eNB, the simultaneous transmission capability information indicating whether or not the mobile station UE is able to transmit uplink data signal via multiple carriers in multiple bands within a same sub-frame in performing uplink CA; performing scheduling for the mobile station UE by the radio base station eNB based on the simultaneous transmission capability information; and performing communications by the mobile station UE based on the scheduling information.

Abstract: To improve probability of successfully performing transmission processing by a priority terminal and transmission processing of an emergency call even during congestion. A mobile communication method according to the present invention includes the steps of: causing a radio base station eNB to transmit “UE Context Release Request” regarding a predetermined mobile station UE to a mobility management node MME, the “UE Context Release Request” containing identification information of multiple target mobile stations UE; causing the mobility management node MME to release an access bearer of the predetermined mobile station UE in response to the “UE Context Release Request”, and transmit “UE Context Release Command” regarding the predetermined mobile station UE to the radio base station eNB, and causing the radio base station eNB to transmit “RRC Connection Release” to the plurality of target mobile stations UE.

Abstract: A radio base station PhNB managing a phantom cell is enabled to uniquely identify a mobile station UE in communication in the phantom cell. A mobile communication method according to the present invention includes starting, by the radio base station PhNB#10, a “Non-contention based RA procedure” or a “Contention based RA procedure” with a mobile station UE#1 in communication in a cell #10 under control of the radio base station PhNB#10; and notifying, by the mobile station UE#1, the radio base station PhNB#10 of a C-RNTImacro which is allocated in a cell #1 other than the cell #10.

Abstract: The present invention is designed to provide a base station apparatus, a radio communication terminal, a radio communication system and a radio communication method which can reduce the cost required for MTC terminals when an LTE system is employed in the network domain of a machine communication system. A base station apparatus communicates with a first communication terminal in a first frequency band and also communicates with a second communication terminal in a second frequency band of a narrower bandwidth than the first frequency band, and includes: an allocation control section that allocates an extended downlink control channel which is frequency-division-multiplexed with a downlink shared data channel, in a predetermined frequency region in the second frequency band; and a mapping section that maps a common control signal that is common between the second communication terminals at least, in a common search space of the extended downlink control channel.

Abstract: A mobile communication method includes the steps of transmitting a first control signal including an identifier different from a C-RNTI to the mobile station UE#A through a FDCCH by a radio base station PhNB#10 managing a cell #10 formed by linking multiple small cells, transmitting a second control signal including an identifier to the mobile station UE through a PDCCH by a radio base station eNB#1 managing a cell #1 having a coverage area overlapping with a coverage area of the cell #10, and regarding the first control signal as valid by the mobile station UE#A, when it determines that the identifier included in the first control signal and the identifier included in the second control signal match each other.

Abstract: An objective is to improve communication quality by reducing an insertion loss or the like of a diplexer inserted to reduce a leakage from an uplink band to a downlink band in different bands. A mobile communication method according to the present invention includes the steps of: transmitting simultaneous transmission capability information from a mobile station UE to a radio base station eNB, the simultaneous transmission capability information indicating whether or not the mobile station UE can transmit uplink data signals via multiple carriers in the same sub-frame while performing uplink CA; performing scheduling for the mobile station UE by the radio base station eNB on the basis of the simultaneous transmission capability information; and performing communication by the mobile station UE on the basis of the scheduling information.

Abstract: To transmit a “CELL UPDATE message” in a radio access network not supporting “Additional Dynamic Transport Format Information for CCCH,” a mobile station UE according to the present invention includes a transmitting unit 13 configured to transmit a “CELL UPDATE message” to a radio access network in a “CELL UPDATE procedure,” and the transmitting unit 13 includes a predetermined information element in the “CELL UPDATE message” only when the radio access network supports the “Additional Dynamic Transport Format Information for CCCH.