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: The base station allocates, to one terminal, at least one transmission layer and allocates at least one resource block that is a minimum allocation unit of a communication resource in each transmission layer, to transmit a signal to the terminal, and includes processing units each associated with one of the transmission layers, the processing units being equal in number to the transmission layers. Each processing unit includes a reference signal generation unit to generate a reference signal to be used by the terminal in demodulation processing on a received signal, and an information processing unit to determine an arrangement of the resource block in which to transmit the reference signal to the terminal, based on at least one of a state of a channel between the base station and the terminal or information on the resource block to be used in transmission of the reference signal in an adjacent cell.

Abstract: Provided is a communication system capable of suppressing increase in the power consumption of a communication terminal device, degradation in the communication quality, and reduction in the use efficiency of radio resources. A base station device (gNB) notifies a communication terminal device (UE) of information on the next reception timing. The UE receives, for example, a downlink control signal (902) in a subframe (901). The UE obtains, from the downlink control signal (902), information on a piece of user data (903) in the subframe (901), and the information (904) on the next reception timing. The UE transmits and receives the piece of user data (903) to and from the gNB. The information (904) on the next reception timing indicates a subframe (905) as the next reception timing of the UE. The UE receives a downlink control signal (906) in the subframe (905).

Abstract: Provided is a communication system capable of suppressing decrease in a transmission rate. An eNB communicates with a UE using a self-contained subframe. The self-contained subframe includes a downlink signal to be transmitted from the eNB to the UE, and an uplink signal to be transmitted from the UE to the eNB in response to the downlink signal. The uplink signal has a structure including an uplink control signal indicating information for controlling transmission of the uplink signal, and uplink user data to be transmitted before and after the uplink control signal. The eNB notifies the UE of a structure of the uplink signal.