US Patent 9161322 Configuring base station and wireless device carrier groups

A base station transmits control message(s) to a wireless device configuring secondary cell(s). Each of the secondary cells is assigned to a cell group in a plurality of cell groups comprising a primary cell group and at least one secondary cell group. The control message(s) comprise dedicated parameters. If dedicated parameters comprise a cell group index for the secondary cell, the wireless device assigns the secondary cell to one of the at least one secondary cell group identified by the cell group index. Otherwise, the wireless device assigns the secondary cell to the primary cell group.