Channel-state information and hybrid-ARQ ACK/NACK information for multiple carriers are simultaneously transmitted using a PUCCH Format 3 structure, where the hybrid-ARQ ACK/NACK bits and CSI bits are separately encoded and interleaved. In an example method, a power control offset parameter is calculated (2110) as a linear combination of at least a number N, representing a number of channel-state information bits and a number M, representing a number of hybrid-ARQ ACK/NACK bits. The method continues with the calculating (2120) of a power level for a transmission on a physical uplink control channel (PUCCH), using the power control offset parameter. In some embodiments, encoded channel-state information and hybrid-ARQ ACK/NACK bits are then transmitted (2060) according to the calculated power level. In some embodiments, the linear combination is of the form aN+bM+c, where a, b, and c are non-zero constants.