Abstract: A communication device is a base station that communicates with mobile terminals by radiating communication beams within a coverage, the communication beams including a first beam and a second beam having a shorter radio wave propagation distance than the first beam at a same transmission power, the coverage including a plurality of virtual cells. The communication device includes: a grouping processing unit that groups the plurality of virtual cells such that virtual cells in which mobile terminals capable of uplink communication using the first beam and incapable of uplink communication using the second beam are located are aggregated; and a beam forming unit that controls a radiation direction of the communication beams such that the communication beams are radiated at a same timing to all virtual cells belonging to a same group.

Abstract: Provided is a radio communication technology with low latency and high reliability. A communication system includes a communication terminal (UE), and a plurality of communication apparatuses (a source gNB and a target gNB) configured to perform radio communication with the communication terminal. When the communication terminal switches a communication apparatus to which the communication terminal is connected from a first communication apparatus (the source gNB) to a second communication apparatus (the target gNB), the communication terminal corrects a time of the communication terminal, based on a timing reference to be transmitted from the second communication apparatus and timing advance of the second communication apparatus (Step ST1512).

Abstract: A resource allocation device includes: an information acquisition unit that acquires information regarding a slice requested by a target terminal which is a terminal as a target to which a slice is to be allocated, information regarding a base station to which the target terminal is to be connected, and information regarding a time at which a slice request is received from the target terminal, and stores the information in a storage unit; a data analysis unit that specifies a communication environment of the target terminal on the basis of information stored in the storage unit; and a slice allocation unit that allocates a slice to the target terminal on the basis of the communication environment of the target terminal.

Abstract: A radio communication technology for enabling high reliability, a high transmission rate, and low power consumption is provided. A communication system includes a communication terminal and a base station. The base station includes a plurality of transmitter-receivers configured to perform radio communication with the communication terminal. The base station is configured to perform radio communication with the communication terminal by using a part or all of the plurality of transmitter-receivers. The communication terminal receives a downlink synchronization signal from at least one first transmitter-receiver to be newly connected, and establishes downlink synchronization with the at least one first transmitter-receiver by using the downlink synchronization signal. The communication terminal establishes uplink synchronization with the at least one first transmitter-receiver through random access processing.

Abstract: A communication system includes a communication terminal, base stations performing radio communication with the communication terminal, and a host device of the base stations. A serving base station of the communication terminal or the host device selects, from among the base stations, a positioning base station transmitting a positioning signal for measuring a position of the communication terminal. The positioning base station transmits the positioning signal, and the communication terminal receives the positioning signal.

Abstract: Provided is a communication system with low latency and high reliability, etc. Even after transitioning from RRC_CONNECTED to RRC_INACTIVE, a communication terminal device maintains secondary base station configuration information on configuring a secondary base station. Even when at least one of a master base station and a secondary base station is changed during the RRC_INACTIVE, the communication terminal device maintains the secondary base station configuration information. The communication terminal device again transitions to the RRC_CONNECTED using the maintained secondary base station configuration information.

Abstract: Provided is a radio communication technology that can achieve low latency, high reliability, and low jitter characteristics. A transmitter is configured to duplicate a packet and transmit the duplicated packets. The receiver is configured to receive the duplicated packets. The receiver is configured to transfer, to an upper layer in the receiver, a first packet (1401, 1403, 1405, 1408) that is a packet received earlier out of the duplicated packets. A transfer timing that is a timing with which the first packet (1401, 1403, 1405, 1408) is transferred to the upper layer includes at least one of: a reception timing of a second packet (1402, 1404, 1406, 1407) that is a packet received later than the first packet out of the duplicated packets; and a cyclical timing (Cycle time) corresponding to a transmission cycle of the duplicated packets.

Abstract: A wireless device is a wireless device operable to switch between a function of a master wireless device and a function of a slave wireless device in a group to which multiple wireless devices belong, where the multiple wireless devices communicate with each other using a synchronization signal, the master wireless device controls another wireless device belonging to the group, and the slave wireless device is controlled by the master wireless device. The wireless device includes a transmission unit capable of transmitting a signal, a reception unit capable of receiving a signal, and a control unit that causes the transmission unit to transmit, toward the master wireless device, information about a synchronization signal detected, when the wireless device is operating as the slave wireless device, and the reception unit receives and detects the synchronization signal from a wireless device not belonging to the group.

Abstract: A radio communication technology for enabling high reliability, a high transmission rate, and low power consumption is provided. A communication system includes a communication terminal and a base station. The base station includes a plurality of transmitter-receivers configured to perform radio communication with the communication terminal. The base station is configured to perform radio communication with the communication terminal by using a part or all of the plurality of transmitter-receivers. The communication terminal receives a downlink synchronization signal from at least one first transmitter-receiver to be newly connected, and establishes downlink synchronization with the at least one first transmitter-receiver by using the downlink synchronization signal. The communication terminal establishes uplink synchronization with the at least one first transmitter-receiver through random access processing.

Abstract: A communication device is a base station that communicates with mobile terminals by radiating communication beams within a coverage, the communication beams including a first beam and a second beam having a shorter radio wave propagation distance than the first beam at a same transmission power, the coverage including a plurality of virtual cells. The communication device includes: a grouping processing unit that groups the plurality of virtual cells such that virtual cells in which mobile terminals capable of uplink communication using the first beam and incapable of uplink communication using the second beam are located are aggregated; and a beam forming unit that controls a radiation direction of the communication beams such that the communication beams are radiated at a same timing to all virtual cells belonging to a same group.

Abstract: Provided is a radio communication technology with high reliability. A communication system includes a communication terminal, base stations, and a host device of the base stations. A serving base station of the communication terminal or the host device selects, from among the base stations, a positioning base station transmitting a positioning signal for measuring a position of the communication terminal. The positioning base station transmits the positioning signal, and the communication terminal receives the positioning signal.

Abstract: Provided is a radio communication technology with low latency and high reliability. A communication system includes a communication terminal, and a plurality of communication apparatuses configured to perform radio communication with the communication terminal. When the communication terminal switches a communication apparatus to which the communication terminal is connected from a first communication apparatus to a second communication apparatus, the communication terminal corrects a time of the communication terminal, based on a timing reference to be transmitted from the second communication apparatus and timing advance of the second communication apparatus.

Abstract: A radio communication technology that can achieve low latency, high reliability, and low jitter characteristics. A transmitter is configured to duplicate a packet and transmit the duplicated packets. The receiver is configured to receive the duplicated packets. The receiver is configured to transfer, to an upper layer in the receiver, a first packet that is a packet received earlier out of the duplicated packets. A transfer timing that is a timing with which the first packet is transferred to the upper layer includes at least one of: a reception timing of a second packet that is a packet received later than the first packet out of the duplicated packets; and a cyclical timing (Cycle time) corresponding to a transmission cycle of the duplicated packets.

Abstract: Provided is a communication system with low latency and high reliability, etc. Even after transitioning from RRC_CONNECTED to RRC_INACTIVE, a communication terminal device maintains secondary base station configuration information on configuring a secondary base station Even when at least one of a master base station and a secondary base station is changed during the RRC_INACTIVE, the communication terminal device maintains the secondary base station configuration information. The communication terminal device again transitions to the RRC_CONNECTED using the maintained secondary base station configuration information.

Abstract: A wireless communication system includes a mobile terminal, multiple lower-layer base stations communicating with the mobile terminal, and an upper-layer base station controlling the lower-layer base stations. The upper-layer base station transmits, to the lower-layer base stations, multiple pieces of first data generated by duplication by the upper-layer base station, and the lower-layer base stations transmit the first data to the mobile terminal. The mobile terminal includes link control units receiving the respective first data correspondingly to the respective lower-layer base stations; and a data control unit that, when a first link control unit of the link control units receives the first data from a first lower-layer base station of the lower-layer base stations, transmits a retransmission request stop message to a second link control unit that hasn't received the first data from a second lower-layer base station being a lower-layer base station other than the first lower-layer base station.

Abstract: A radio communication technology for enabling high reliability, a high transmission rate, and low power consumption is provided. A communication system includes a communication terminal and a base station. The base station includes a plurality of transmitter-receivers configured to perform radio communication with the communication terminal. The base station is configured to perform radio communication with the communication terminal by using a part or all of the plurality of transmitter-receivers. The communication terminal receives a downlink synchronization signal from at least one first transmitter-receiver to be newly connected, and establishes downlink synchronization with the at least one first transmitter-receiver by using the downlink synchronization signal. The communication terminal establishes uplink synchronization with the at least one first transmitter-receiver through random access processing.

Abstract: A wireless control apparatus controls beamforming performed by a wireless base station apparatus that provides a communication service to a service area which includes a plurality of spots to be irradiated with a beam including a terminal search beam and a communication beam that are not used simultaneously for irradiation, and is irradiated with a plurality of the beams and is not simultaneously covered by the plurality of beams, and the apparatus includes: an arrival direction estimation unit that estimates an arrival direction of a wireless signal transmitted by a terminal communicating with a wireless base station; and a control unit that determines whether there is an active terminal in the spots on the basis of the arrival direction estimated by the arrival direction estimation unit, and, when it is determined that there is no active terminal, controls beamforming performed by the wireless base station apparatus to decrease a frequency of the terminal search beam with which one or more of the spots dete

Abstract: A wireless control apparatus controls beamforming performed by a wireless base station apparatus that provides a communication service to a service area which includes a plurality of spots to be irradiated with a beam including a terminal search beam and a communication beam that are not used simultaneously for irradiation, and is irradiated with a plurality of the beams and is not simultaneously covered by the plurality of beams, and the apparatus includes: an arrival direction estimation unit that estimates an arrival direction of a wireless signal transmitted by a terminal communicating with a wireless base station; and a control unit that determines whether there is an active terminal in the spots on the basis of the arrival direction estimated by the arrival direction estimation unit, and, when it is determined that there is no active terminal, controls beamforming performed by the wireless base station apparatus to decrease a frequency of the terminal search beam with which one or more of the spots dete

Abstract: A base station includes: a communication unit capable of transmitting a reference signal to a plurality of beam spots each being a radiation range of a directional beam, the reference signal being used by a terminal in a beam spot to measure a reception quality, and capable of transmitting the reference signal simultaneously to a beam spot group formed of one or more of the beam spots; and a control unit that assigns consecutive time slots for transmitting the reference signal to a beam spot group covering adjacent radiation ranges, of the beam spot groups.

Abstract: A control apparatus for wireless communication system includes: a communication unit to obtain, from a base station, information indicating reception quality, at a terminal device, of a signal transmitted on a directional beam from the base station; and a processing unit to determine whether to remove a spot on the basis of the information obtained by the communication unit, the spot being an area irradiated with a directional beam from the base station. If the processing unit determines that the spot is to be removed, the communication unit sends an instruction to remove the spot to the base station or to a master base station of the base station.