Abstract: Radio resource management is simplified when a cell is spatially separated by a plurality of radio beams. A cell configured by a base station device is spatially separated by a plurality of radio beams being served by the base station device. The base station device shares, between two or more of the plurality of radio beams, a radio resource control (RRC) parameter to be applied to a communication terminal device.

Abstract: A communication system includes: a base station; and a communication terminal connected to the base station, and in a case where the base station causes the communication terminal to transmit a data signal, the base station notifies the communication terminal of information about a demodulation reference signal to be transmitted together with a data signal, and the communication terminal transmits a data signal and a demodulation reference signal in accordance with the information provided from the base station.

Abstract: A communication system includes a base station and a communication terminal connected to the base station. The base station transmits a result of reception of an uplink positioning signal transmitted by the communication terminal and location information of the base station to a positioning device that is a device having a positioning function of deriving a location of the communication terminal, and the communication terminal transmits a result of reception of a downlink positioning signal transmitted by the base station to the positioning device.

Abstract: A communication system includes a user apparatus; and base stations respectively configured to wirelessly communicate with the user apparatus. The base stations include a master base station and a secondary base station that configure dual connectivity for the user apparatus. The secondary base station is configured with a grant configuration related to transmission without grant in uplink to the secondary base station.

Abstract: Radio resource management is simplified when a cell is spatially separated by a plurality of radio beams. A cell configured by a base station device is spatially separated by a plurality of radio beams being served by the base station device. The base station device shares, between two or more of the plurality of radio beams, a radio resource control (RRC) parameter to be applied to a communication terminal device.

Abstract: A communication system that can reduce latency while preventing reduction in a transmission rate. An eNB communicates with a UE #1 using a self-contained subframe including a first downlink signal (DL #1) and a first uplink signal (UL #1), and with a UE #2 using a self-contained subframe including a second downlink signal (DL #2) and a second uplink signal (UL #2). The self-contained subframe for the UE #1 includes a first gap duration (Gap #1) during which neither the DL #1 nor the UL #1 is transmitted, between transmission durations of the DL #1 and the UL #1. The self-contained subframe for the UE #2 includes a second gap duration (Gap #2) during which neither the DL #2 nor the UL #2 is transmitted, between transmission durations of the DL #2 and the UL #2. The Gaps #1 and #2 are set to each UE.

Abstract: The power consumption is reduced in a communication system using Device-to-Device communication. The communication system includes: a base station; a first communication terminal configured to perform radio communication with the base station; and a second communication terminal configured to perform Device-to-Device communication with the first communication terminal. The first communication terminal is configured to relay communication between the second communication terminal and the base station. The first communication terminal releases connection with the base station and transitions to an idle state in the absence of data to be transmitted and received between the second communication terminal and the base station for a predetermined period (Steps ST1411 to ST1415).

Abstract: A communication system including a communication terminal, a base station configured to perform radio communication with the communication terminal, and a management device managing access to the communication terminal through the base station. The communication terminal starts a predefined process for changing Closed Access Group (CAG) information. The management device transmits the CAG information to the communication terminal in response to starting the predefined process by the communication terminal.

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 communication system includes a communication terminal, and a serving base station of the communication terminal. The serving base station notifies the communication terminal of an instruction to configure a measurement gap for the communication terminal to measure a positioning signal transmitted from at least one neighboring base station in order to measure a position of the communication terminal, without a request from the communication terminal (Step ST1417).

Abstract: A user apparatus in a communication system includes: a plurality of user apparatuses each of which is configured to transmit a sounding reference signal (SRS); and a base station configured to wirelessly communicate with the plurality of the user apparatuses. The user apparatus receives, from the base station, configuration information related to a wireless resource of the sounding reference signal allocated to another user apparatus.

Abstract: A communication system includes a terminal apparatus; and a plurality of base stations respectively configured to wirelessly communicate with the terminal apparatus, the base stations including an MgNB and an SgNB that configures dual connectivity with the terminal apparatus. The terminal apparatus performs small data transmission for the SgNB in an RRC_INACTIVE state.

Abstract: A high-speed communication system etc. are provided in New Radio (NR) and LTE. When a secondary base station device detects a data inactive state for all bearers, the secondary base station device notifies a master base station device of occurrence of the data inactive state regardless of absence of an inquiry from the master base station device. The data inactive state is a state in which downlink data for a communication terminal device is inactive. When the master base station device receives the notification about the occurrence of the data inactive state, the master base station device transmits a command to the communication terminal device to transition from an RRC_CONNECTED state to an RRC_INACTIVE state. Based on the command from the master base station device, the communication terminal device transitions to the RRC_INACTIVE state.

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 user apparatus; and a base station including a distributed unit (DU) configured to wirelessly communicate with the user apparatus and a central unit (CU) connected to the distributed unit. The base station including the CU and the DU supports packet duplication, and the DU notifies the user apparatus of starting the packet duplication.

Abstract: A high-speed communication system etc. are provided in New Radio (NR) and LTE. When a secondary base station device detects a data inactive state for all bearers, the secondary base station device notifies a master base station device of occurrence of the data inactive state regardless of absence of an inquiry from the master base station device. The data inactive state is a state in which downlink data for a communication terminal device is inactive. When the master base station device receives the notification about the occurrence of the data inactive state, the master base station device transmits a command to the communication terminal device to transition from an RRC_CONNECTED state to an RRC_INACTIVE state. Based on the command from the master base station device, the communication terminal device transitions to the RRC_INACTIVE state.

Abstract: Better communication is provided. A communication system includes a communication terminal, and a base station configured to perform radio communication with the communication terminal. The communication terminal or the base station determines whether the base station supports a desired slice that is a Radio Access Network slice that the communication terminal desires to use.

Abstract: Provided is a high-speed communication system with the high reliability and the low latency under New Radio (NR). A base station device includes a plurality of distributed units (DUs, 802) that transmit and receive radio signals, and a central unit (CU, 801) that controls the plurality of DUs (802). The CU (801) duplicates a downlink packet addressed to a communication terminal device (804), and forwards the duplicated downlink packet to each of at least two DUs (802) among the plurality of DUs (802). Each of the at least two of the DUs (802) transmits, to the communication terminal device (804) by the radio signal, the downlink packet obtained from the CU (801). Upon redundant receipt of the downlink packets, the communication terminal device (804) removes a redundant downlink packet in accordance with a predefined downlink packet removal criterion.

Abstract: A communication system includes a communication terminal, and a plurality of networks configured to perform radio communication with the communication terminal. A priority of at least one of a paging timing and a paging type is assigned to a paging to be transmitted from each of the plurality of networks. The communication terminal selects a corresponding one of the pagings to be received, based on the priority.

Abstract: Satisfactory SL communication is provided. A communication system includes: a first communication terminal; a second communication terminal configured to perform inter-terminal communication with the first communication terminal; and a third communication terminal configured to perform inter-terminal communication with the first communication terminal. The third communication terminal reports resource information for the inter-terminal communication between the first communication terminal and the second communication terminal to the first communication terminal via an interface for the inter-terminal communication between the first communication terminal and the third communication terminal.