TERMINAL DEVICE, BASE-STATION DEVICE, COMMUNICATION SYSTEM, METHOD FOR CONTROLLING TRANSMISSION OF TERMINAL DEVICE, METHOD FOR CONTROLLING TRANSMISSION OF BASE-STATION DEVICE, INTEGRATED CIRCUIT INSTALLED IN TERMINAL DEVICE, AND INTEGRATED CIRCUIT INSTALLED IN BASE-STATION DEVICE

摘要

A terminal device (1) aggregating a plurality of cells and connected to a base-station device (2), wherein on the basis of transmission-timing group settings transmitted from the base-station device (2), cells of differing frequencies are grouped, and for each group the following are set: a timing-reference cell that is the standard for uplink transmission timing for the cells in the group, a group identifier for identifying the group, and a transmission-timing timer showing the effective time of uplink transmission timing for the cells in the group. When the timing-reference cell in a group no longer exists due to a change in a cell on the basis of a change-instruction message transmitted from the base-station device (2) instructing a change to a cell in the group, the setting for the transmission-timing group pertaining to the group is released.