Patent attributes
A base station transmits control message(s) to a wireless device configuring secondary cell(s). The control messages comprise common parameters and dedicated parameters. The common parameters comprise random access resource parameters and power control parameters for a secondary cell. The dedicated parameters comprise a cell group index for a secondary cell and a time alignment timer for a secondary cell group. The base station transmits a control command causing transmission of a random access preamble on the random access resources of the secondary cell. Transmission power of the random access preamble is calculated employing the power control parameters.