Abstract: A communication device according to embodiment comprises a transmitter configured to transmit first information to a plurality of other communication devices, via a communication scheme in which communication is performed without synchronization between devices; and a receiver configured to receive second information as a response to reception of the first information from the plurality of other communication devices via the communication scheme. The transmitter is configured to transmit, to each communication device of the plurality of other communication devices, transmission timing information for each communication device of the plurality of other communication devices to designate a transmission timing of the second information.

Abstract: A radio terminal according to an embodiment comprises: a controller configured to execute processing of establishing connection with a network for relaying using a Device to Device (D2D) proximity service; a transmitter configured to transmit a discovery message for the relaying, after the connection is established; and a receiver configured to receive a request message from another radio terminal that has received the discovery message, wherein the request message includes an identifier of the another radio terminal. The controller executes control of transmitting the identifier of the another radio terminal, to a network apparatus included in an Evolved Packet Core (EPC), as an identifier of a remote node to which data is relayed by the relaying. The controller executes control of further transmitting the identifier of the another radio terminal to the network apparatus, based on non-reception of a predetermined message from the another radio terminal.

Abstract: A base station transmits, to a user terminal, a connection release request for requesting a release of an RRC connection. The connection release request includes information indicating a request of holding an identifier assigned by the base station, and the information causes the user terminal in an idle state to hold the identifier. The base station performs a random access procedure with the user terminal in the idle state. The random access procedure includes receiving a random access signal from the user terminal, transmitting a random access response that is a response to the random access signal, to the user terminal, and receiving a control signal together with the identifier from the user terminal after transmitting the random access response, while the user terminal is in the idle state.

Abstract: A base station according to an embodiment comprises: a controller configured to receive an identifier of a wireless LAN access point added in a wireless LAN termination apparatus from the wireless LAN termination apparatus.

Abstract: A user terminal includes: a receiver configured to receive multicast/broadcast data transmitted from a base station to a plurality of user terminals using the same downlink radio resources; a controller configured to select uplink radio resources to be used for transmission of feedback information, from a resource pool allocated from the base station to a group including the plurality of user terminals; and a transmitter configured to transmit the feedback information to the base station using the selected uplink radio resources.

Abstract: A communication control method comprises: receiving, by a user terminal, from a base station, first information indicating a Device to Device (D2D) frequency available in a D2D discovery procedure for discovering a proximal terminal; and using, by the user terminal, not only the frequency indicated by the first information, but also a frequency not indicated by the first information. The frequency not indicated by the first information is different from the frequency indicated by the first information and is indicated by second information received from another cell different from a cell in which the user terminal exists.

Abstract: A mobile communication system, which supports D2D communication that is direct device-to-device communication that is performed by using a radio resource assigned from a network, comprises: a user terminal that transmits a D2D start request for starting the D2D communication to the network, wherein the D2D start request includes an application identifier indicating an application used by the user terminal in the D2D communication, and a terminal identifier indicating another user terminal that is a communication partner of the user terminal in the D2D communication.

Abstract: A radio terminal according to one embodiment transmits data of one bearer to two radio communication apparatuses. The radio terminal comprises a controller configured to transmit a buffer status report to only one of the two radio communication apparatuses, if a data amount accumulated in a predetermined buffer falls below a threshold value and only the one radio communication apparatus is designated as a transmission target of the buffer status report. The controller is configured to change the transmission target of the buffer status report from the one radio communication apparatus to the other radio communication apparatus, if the data amount falls below the threshold value and a failure in a radio link with the one radio communication apparatus is detected.

Abstract: A communication method, user terminal, processor, and base station for direct communication including a user terminal transmitting to a base station, buffer status information indicating amounts of data to be transmitted in direct communication, where each amount of data is for each of logical channel groups for the direct communication and for each communication partner of the direct communication, assigning, by the base station to the user terminal, a radio network temporary identifier for the direct communication, determining, by the base station, a radio resource to be used for the user terminal to perform the direct communication, transmitting, from the base station to the user terminal, resource information indicating the determined radio resource, by use of the radio network temporary identifier assigned to the user terminal, and receiving, by the user terminal, the resource information on a basis of the radio network temporary identifier assigned to the user terminal.

Abstract: A base station in a system supporting WWAN-WLAN aggregation communication in which a radio terminal performs communication using WWAN communication and WLAN communication simultaneously. The base station includes a controller configured to acquire capability information indicating a function of the radio terminal, wherein a first function and a second function are defined. The first function splits a bearer of the radio terminal in a PDCP layer of the WWAN communication, and uses the WWAN communication and the WLAN communication for radio communication of the bearer. The second function uses only the WLAN communication for the radio communication of the bearer without splitting the bearer going through the PDCP layer. The controller is configured to acquire capability information of the second function as information different from capability information of the first function.

Abstract: A user terminal according to first to third embodiments is used in a mobile communication system defined to observe a use state of an unlicensed band channel within an observation period before transmitting an uplink signal within an uplink transmission period in the channel. The user terminal includes a controller configured to perform transmission restriction to restrict transmission of the uplink signal during a last fixed section or a first fixed section of the uplink transmission period when transmitting the uplink signal within the uplink transmission period in the channel.

Abstract: A user terminal according to an embodiment includes a receiver that receives a list transmitted from a base station, the list including discovery resource configurations; and a controller that selects a discovery resource configuration from among the discovery resource configurations, and uses the selected discovery resource configuration to directly transmit a discovery signal to other user terminals. Each of the discovery resource configurations includes: time resource information indicating time resources used for transmitting a discovery signal and including a variable number substituted into a mathematical expression; frequency resource information indicating frequency resources used for transmitting the discovery signal and including a range of continuous resource block numbers; and power information indicating transmission power used for transmitting the discovery signal.

Abstract: A communication device according to one embodiment comprise a transmitter configured to directly transmit a radio signal to another communication device. The transmitter is configured to transmit, when first location information indicating a geographical location of the communication device is acquired, the radio signal, based on a first radio resource associated with a location indicated by the first location information. The transmitter is configured to transmit, when the communication device cannot acquire the first location information, the radio signal, based on a second radio resource. The second radio resource is decided based on a method different from a method of deciding the first radio resource by using the first location information.

Abstract: A communication control method includes: a step A of receiving, by UE 100-1 in a coverage of the mobile communication system, broadcast information transmitted from eNB 200; a step B of transferring, by the UE 100-1, the broadcast information to UE 100-2 outside the coverage of the mobile communication system; and a step C of receiving, by the UE 100-2, the broadcast information transferred from the UE 100-1.

Abstract: When a UE 100-2 (a reception-side UE) that performs D2D communication by using UL radio resource switches communication modes between cellular communication and the D2D communication, if DL subframe in which data reception of the cellular communication should be performed and the UL subframe in which data reception of the D2D communication should be performed at least partially overlap on a time axis, then the UE 100-2 performs data reception in one subframe, out of the overlapping two subframes.

Abstract: A communication control method, user equipment and apparatus thereof include transmitting, to a base station by a user equipment, first information on a priority of a data pack to be transmitted from the user equipment via direct communication in which the data packet is transmitted to another user equipment without passing through the base station. The first information assists the base station in scheduling transmission resources for the direct communication. The method, user equipment and apparatus also include transmitting a request for requesting transmission resources for the direct communication to the base station by the user equipment, and receiving by the user equipment from the base station second information indicating transmission resources for the direct communication scheduled by the base station.

Abstract: A radio terminal according to one embodiment comprises: a controller configured to detect a radio problem in communication with a base station in an RRC connected state and attempt a recovery from the radio problem; and a transmitter configured to transmit, to the base station, a polling signal for confirming whether or not the base station considers an RRC state of the radio terminal as the RRC connected state in response to the successful recovery. The controller maintains the RRC connected state in response to reception, from the base station, of a response signal to the polling signal.

Abstract: In a communication control method according to a present embodiment, at least one radio terminal of a first radio terminal and a second radio terminal discoveries the other radio terminal by executing a discovery for discovering a proximal terminal. The at least one radio terminal reports, to a network apparatus that the other radio terminal is discovered. The network apparatus requests, while the first radio terminal is located within a coverage of a cell, at least one of the first radio terminal and the second radio terminal to make a preparation for executing a relay by the second radio terminal by utilizing a proximal service.

Abstract: eNB 200 controls wireless connections established by UE 100-1 with other communication apparatuses. The eNB 200 performs control such that number of the wireless connections established by the UE 100-1 is equal to or less than a connection allowance number indicating an upper limit number of the wireless connections allowed to the UE 100-1.

Abstract: A radio terminal according to one embodiment is configured to perform a relay between another radio terminal and a network. The radio terminal comprises: a transmitter configured to notify the network of first information indicating that the radio terminal is a relay terminal of the another radio terminal; a controller configured to forward data addressed to the another radio terminal to the another radio terminal via a connection between the another radio terminal through the radio terminal and the network; and a receiver configured to receive from the network a message indicating that the data addressed to the another radio terminal exists when at least part of the connection is released. The controller is configured to start control for establishing the connection in order to forward the data addressed to the another radio terminal in response to receiving the message.