Patent attributes
A user equipment has a transmission and reception unit configured to transmit and receive a radio channel to/from a base station via multiple cells configured by carrier aggregation, a simultaneous transmission availability determination unit configured to, in response to an occurrence of an event to transmit an uplink control channel in the multiple cells simultaneously, determine whether the uplink control channel can be simultaneously transmitted in the multiple cells, and a transmission control unit configured to, if the uplink control channel can be simultaneously transmitted in the multiple cells, instruct the transmission and reception unit to transmit the uplink control channel in the multiple cells simultaneously, and if the uplink control channel cannot be simultaneously transmitted in the multiple cells, control transmission of the uplink control channel in accordance with a transmission priority.