Abstract: An object is to increase opportunities for starting “Inter-band CA”. A mobile station UE of the present invention includes a transmission unit 14 configured to postpone transmission of a random access preamble in a cell #2 when the mobile station UE in a “RRC_Connected state” in a cell #1 detects a start trigger of a random access procedure in the cell #2, and determines that an uplink signal is being transmitted in the cell #1. The transmission unit 14 performs the postponed transmission of the random access preamble upon completing the transmission of the uplink signal in the cell #1.

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: User equipment of a radio communication system including a base station that performs communication using a maximum bandwidth which is a largest bandwidth available for communication and the user equipment in which a largest bandwidth available for communication is equal to or less than the maximum bandwidth, the user equipment including a receiver unit configured to receive a radio signal transmitted from the base station; and an acquisition unit configured to acquire a radio resource of a master information block corresponding to a synchronization signal, a radio resource of a system information block, and a radio resource of a paging channel, wherein the receiver unit monitors the radio resource of the synchronization signal, the radio resource of the master information block, the radio resource of the system information block, or the radio resource of the paging channel, when the user equipment is in an RRC idle mode.

Abstract: Disclosed is a radio communication system capable of implementing a state transition related to an intermediate state between a connected state and an idle state. An aspect of the present invention relates to a user equipment, wherein the user equipment includes a state management unit that manages a communication state of the user equipment, and a state transition unit that causes the communication state of the user equipment to transition, and when the user equipment is communicating with the first base station, if cell reselection for the second base station is performed, the state transition unit performs the cell reselection for the second base station while the state management unit retains first radio parameter information for radio communication between the user equipment and the first base station and a first context identifier specifying the first radio parameter information.

Abstract: A user equipment is disclosed including a receiver that receives an RRC message related to configuration information of a second radio base station for a split hearer that splits from the second radio base station toward a first radio base station, and a processor that releases resources related to a radio link of the second radio base station based on the RRC message when a radio link failure in the second radio base station is detected.

Abstract: A technology for realizing an efficient parallelization process in PDCP/RLC layers is provided. According to an embodiment of the invention, a radio communication apparatus includes: a PDCP processing unit configured to perform a process in a PDCP layer; an RLC processing unit configured to perform a process in an RLC layer; and a MAC processing unit configured to perform a process in a MAC layer. The RLC processing unit includes a plurality of RLC entities and the MAC processing unit includes a single MAC entity.

Abstract: It is an objective of the present invention to suppress an influence on a downlink and to appropriately control a transmission rate of uplink user data. A mobile communication system according to the present invention includes: a transmission section for transmitting to a mobile station an exclusive channel for notifying a mobile station of transmission rate information regarding a transmission rate of user data of an uplink channel; and a transmission rate control section for determining transmission rate information to be used by the mobile station and to instruct the mobile station to receive the exclusive channel for notifying the determined transmission rate information. The transmission section transmits, to the mobile station, the exclusive channel for notifying the determined transmission rate information.

Abstract: A base station is provided. The base station includes a first reception unit configured to receive, from a user apparatus included in a mobile communication system including the base station, another base station communicating with the base station, and the user apparatus communicating with the base station, first data including quality information used for scheduling controlling performed by the other base station, and second data different from the first data. The base station also includes a transmission unit configured to transmit the first data to the other base station by giving higher priority to the first data than to the second data.

Abstract: A user equipment in a wireless communication system that includes a base station and the user equipment, the user equipment includes: a reception unit that receives allocations of radio resources to be used for transmitting uplink reference signals from the base station; a measurement unit that measures reception quality of downlink signals transmitted from the base station; and a transmission unit that starts transmitting uplink reference signals using the radio resources allocated from the base station when the reception quality measured by the measurement unit satisfies a predetermined condition and stops transmission of uplink reference signals when the reception quality measured by the measurement unit does not satisfy the predetermined condition.

Abstract: Provided is a radio communication system capable of implementing a state transition related to an intermediate transition between a connected state and an idle state.

Abstract: Disclosed is a radio communication system capable of implementing a state transition related to an intermediate state between a connected state and an idle state. An aspect of the present invention relates to a user equipment, wherein the user equipment includes a state management unit that manages a communication state of the user equipment, and a state transition unit that causes the communication state of the user equipment to transition, and when the user equipment is communicating with the first base station, if cell reselection for the second base station is performed, the state transition unit performs the cell reselection for the second base station while the state management unit retains first radio parameter information for radio communication between the user equipment and the first base station and a first context identifier specifying the first radio parameter information.

Abstract: Provided is a communication system that can sustain a reduction in delay in FFT/IFFT processing by code blocking user data, even in a case where the functions of upper layers such as a MAC scheduler and the function of the radio physical layer are implemented separately. In a radio base station (communication system) including a central aggregation device 210 and a remote device 220, the central aggregation device 210 transmits code blocks in a number necessary for generating an OFDM symbol as a piece of data to the remote device 220, the code blocks being produced by dividing user data into units of encoding processing.

Abstract: Provided are a radio communication system and user device that enable smooth interworking in a radio resource control (RRC) layer in the case of implementing interworking between systems by LTE assisted 5G, 5G assisted LTE, or the like. The radio communication system includes an eNB 100 conforming to LTE and a 5G-BS 200 conforming to 5G. The eNB 100 includes an RRC function unit 110 that performs control based on LTE-RRC, which is an RRC protocol in LTE. The 5G-BS 200 includes an RRC function unit 210 that performs control based on 5G-RRC, which is the RRC protocol in 5G. The RRC function unit 210 has at least a function not specified in LTE-RRC.

Abstract: One object is to provide a radio base station and a communication control method in which a remote device can correctly transmit downlink data based on radio resource assignment information from a central aggregation device even when a function of an upper layer such as MAC scheduler and a function of a radio physical layer are mounted separately. The method includes transmitting including a central aggregation device (210) of a radio base station transmitting to a remote device (260) a frame containing each of assignment information indicating radio resource assignment and downlink data that is data transmitted to a user device (300), and transmitting including the remote device (260), based on the received frame, transmitting the assignment information to the user device (300) via PDCCH and transmitting the downlink data to the user device (300) via DLSCH.

Abstract: A technique of promptly implementing appropriate flow control in distributed transmission is provided. An aspect of the present invention relates to a base station serving as a distribution source base station in distributed transmission in which transmission target packets are divided and transmitted from a plurality of base stations to a user equipment, wherein the base station includes a feedback information acquiring unit that acquires radio environment information of a distribution destination base station in the distributed transmission; and a communication control unit that controls the distributed transmission according to the radio environment information.

Abstract: There is provided user equipment for communicating with a first base station and a second base station, the user equipment including a receiver that receives, form the first base station or the second base station with which an RRC connection is established, a first message indicating to establish a split bearer between the first base station and the second base station; and a communicator that establishes the split bearer between the first base station and the second base station that are reported by the first message, wherein, in the split bearer, a process of a PDCP layer is performed by one of the first base station and the second base station.

Abstract: A communication control method according to the present invention is implemented in a radio base station (200) including a remote device (260) and a central aggregation device (210) and that performs radio communication with a user device (300). The communication method includes acquiring including the remote device (260) acquiring via a predetermined uplink channel downlink quality information indicating radio communication quality in downlink acquired by the user device (300); transmitting including the remote device (260) transmitting to the central aggregation device (210) a quality data series containing one or more pieces of the downlink quality information acquired at the acquiring; and performing including the central aggregation device (210) performing assignment of a radio resource to the user device (300) based on the quality data series.

Abstract: The communication control method includes transmitting including a central aggregation device (210) of a radio base station transmitting to a remote device (260) system information (SIB) that is notified to a user device (300) and assignment information indicating radio resource assignment used for notifying the system information, and transmitting including the remote device (260) transmitting the system information to the user device (300) via a predetermined downlink channel based on received assignment information. The transmitting the assignment information to the remote device (260) includes, when the contents of the system information or the assignment information is changed, transmitting the contents changed system information or the contents changed assignment information.

Abstract: Provided is a base station used as a first base station in a radio communication system including the first base station, a second base station communicating with the first base station, and a user equipment communicating with the first base station. The base station includes: an acquiring unit that acquires a plurality of parameters used for an initial cell setting; and a setting unit that performs a cell setting using the acquired plurality of parameters.

Abstract: A base station is provided that includes an obtainer that obtains a first parameter used for generation of a signal of a physical downlink control format indicator channel, a second parameter used for generation of a signal of a physical downlink HARQ indicator channel, or a third parameter used for generation of a signal of a physical downlink control channel; a generator that generates the signal of the physical downlink control format indicator channel, the signal of the physical downlink HARQ indicator channel, or the signal of the physical downlink control channel using the first parameter, the second parameter, or the third parameter; and a transmitter that transmits the generated signal of the physical downlink control format indicator channel, the generated signal of the physical downlink HARQ indicator channel, or the generated signal of the physical downlink control channel.