Abstract: A UE performs communication with another UE. A UE detects another communication different from the communication. The UE has a predetermined communication resource selection rule stored therein. The UE controls the communication. When the other communication is detected, the UE selects a communication resource based on the stored communication resource selection rule. This allows radio waves to be utilized efficiently.

Abstract: A UE, which is a mobile terminal, is capable of a device-to-device communication. The UE displays, on a display unit, an LTE antenna picto based on a reception level of a radio wave transmitted by a base station, and a D2D antenna picto based on a reception level of a radio wave transmitted by a UE over the device-to-device communication. According to the UE, the reception level of the radio wave in the device-to-device communication can be immediately confirmed, as well as a reception level of a radio wave in communication with the base station.

Abstract: A wireless communication system includes a first base station device, a second base station device, a mobile station device configured to communicate with the first base station device using a first component carrier and to communicate with the second base station device using a second component carrier. The first base station device includes a disconnection preparation requesting unit configured to transmit to the second base station device, a disconnection preparation request that requests the second base station device to prepare to disconnect the second component carrier.

Abstract: A wireless communication system allows a handover operation to a base station communicating through a plurality of frequency bands. The mobile terminal includes a communication unit adapted to perform communication with any of the base stations through a plurality of frequency bands. The communication unit of the base station notifies, when communication through a plurality of frequency bands is possible, a mobile terminal about information directed to identifying a main frequency band from relevant frequency bands in a manner allowing discrimination from one or more frequency bands other than the main frequency band. The communication unit of the mobile terminal determines that, upon receiving information directed to identifying a main frequency band from the second base station during having communication connection with the first base station, that the frequency band identified by the relevant information is a subject of handover towards the second base station.

Abstract: A wireless communication system includes a plurality of base station devices, and a mobile station device configured to communicate with the plurality of base station devices. The mobile station device includes: a necessity determining unit configured to refer to a communication state of a first base station device that is a base station device in communication with the mobile station device, and determine necessity of carrier aggregation; a cell search unit configured to, in a case that the necessity determining unit determines that carrier aggregation is necessary, search a communication available base station device from the plurality of base station devices; and a carrier aggregation requesting unit configured to, in a case that at least one communication available base station device is detected by the search, transmit a request for carrier aggregation to the first base station device, thus providing a wireless communication system that can obtain an excellent speed.

Abstract: A wireless communication system includes a first base station device, a second base station device, and a mobile station device configured to communicate with the first and second base station devices. The first base station device includes a request notifying unit configured to notify the mobile station device of a request for carrier aggregation. The mobile station device includes: a cell search unit configured to, upon receiving the request, perform cell search and thereby search the second base station device available for carrier aggregation; and a base station notifying unit configured to notify the first base station device of information indicating the second base station device detected by the cell search unit performing the cell search.

Abstract: A wireless communication system includes a first base station device, a second base station device, a mobile station device configured to communicate with the first base station device using a first component carrier and to communicate with the second base station device using a second component carrier. The first base station device includes a disconnection preparation requesting unit configured to transmit to the second base station device, a disconnection preparation request that requests the second base station device to prepare to disconnect the second component carrier.

Abstract: A wireless communication system includes a plurality of base station devices, and a mobile station device configured to communicate with the plurality of base station devices. The mobile station device includes: a necessity determining unit configured to refer to a communication state of a first base station device that is a base station device in communication with the mobile station device, and determine necessity of carrier aggregation; a cell search unit configured to, in a case that the necessity determining unit determines that carrier aggregation is necessary, search a communication available base station device from the plurality of base station devices; and a carrier aggregation requesting unit configured to, in a case that at least one communication available base station device is detected by the search, transmit a request for carrier aggregation to the first base station device, thus providing a wireless communication system that can obtain an excellent speed.

Abstract: A wireless communication system, a communication method, a base station, and a communication terminal are provided. The wireless communication system includes a base station, and a communication terminal that can communicate with the base station through a plurality of frequency bands. The wireless communication system includes a first notification module provided at one of the base station and communication terminal for notifying the other of the base station and communication terminal of a switching preparation request when a state is detected in which the frequency band used as the main frequency band among the plurality of frequency bands is to be switched, and a second notification module that notifies one of the base station and communication terminal of frequency band switching preparation completion in response to a determination of being in a state in which the frequency band used as the main frequency band is to be switched.

Abstract: A wireless communication system includes a first base station device, a second base station device, and a mobile station device configured to communicate with the first and second base station devices. The first base station device includes a request notifying unit configured to notify the mobile station device of a request for carrier aggregation. The mobile station device includes: a cell search unit configured to, upon receiving the request, perform cell search and thereby search the second base station device available for carrier aggregation; and a base station notifying unit configured to notify the first base station device of information indicating the second base station device detected by the cell search unit performing the cell search.

Abstract: A wireless communication system allows a handover operation to a base station communicating through a plurality of frequency bands. The mobile terminal includes a communication unit adapted to perform communication with any of the base stations through a plurality of frequency bands. The communication unit of the base station notifies, when communication through a plurality of frequency bands is possible, a mobile terminal about information directed to identifying a main frequency band from relevant frequency bands in a manner allowing discrimination from one or more frequency bands other than the main frequency band. The communication unit of the mobile terminal determines that, upon receiving information directed to identifying a main frequency band from the second base station during having communication connection with the first base station, that the frequency band identified by the relevant information is a subject of handover towards the second base station.

Abstract: Provided is an HeNB which can cause a mobile station within a coverage of the HeNB to be handed over to another communicable base station. An HeNB communicates with an MME through a relay process by a gateway. The HeNB detects a state of the gateway. The HeNB stops communication with a mobile phone in accordance with the state of the gateway.