USER DEVICE AND UP-CONTROL-INFORMATION TRANSMISSION METHOD

摘要

A user device in a mobile communication system in which carrier aggregation is conducted using a plurality of cells is equipped with: a control unit for determining whether or not a physical uplink shared channel is set in the user device at the transmission timing of up-control information, and when a physical uplink shared channel is set therein, determining to transmit the up-control information by using the physical uplink shared channel; and a transmission unit for transmitting the up-control information to a wireless base station by using the physical uplink shared channel. Furthermore, the control unit determines to transmit the up-control information by using the physical uplink shared channel when the physical uplink shared channel is set in a first cell among a plurality of cells, and determines to transmit the up-control information by using a physical uplink shared channel in a second cell when a physical uplink shared channel is not set in the first cell.