A method for transmitting control information using a Physical Uplink Control Channel, PUCCH, format 3 by a communication apparatus in a radio communication system, comprising: receiving a radio resource control, RRC, message including a first set of four PUCCH resource values for the PUCCH format 3; detecting a Physical Downlink Control Channel, PDCCH; receiving a Physical Downlink Shared Channel, PDSCH, signal corresponding to the PDCCH signal on a secondary cell, SCell; determining one or more PUCCH resources at least based on a 2-bit value of a transmit power control, TPC, field of the PDCCH signal; and transmitting (S3320, S3330) the control information using the one or more determined PUCCH resources, characterized in: wherein, if a single antenna port transmission mode is configured for the PUCCH format 3, the RRC message has no further set of four PUCCH resource values for the PUCCH format 3, and the 2-bit value of the TPC field is mapped to one of the four PUCCH resource values of the first set of four PUCCH resource values for a first antenna port, and wherein, if a multi-antenna port transmission mode is configured for the PUCCH format 3, the RRC message further comprises a second set of four PUCCH resource values, and the 2-bit value of the TPC field is mapped to one of the four PUCCH resource values of the first set of four PUCCH resource values for the first antenna port and a value of a downlink assignment index, DAI, field of the PDCCH signal is mapped to one of the four PUCCH resource values of the second set of four PUCCH resource values for a second antenna port. receiving a radio resource control, RRC, message including a first set of four PUCCH resource values for the PUCCH format 3; detecting a Physical Downlink Control Channel, PDCCH; receiving a Physical Downlink Shared Channel, PDSCH, signal corresponding to the PDCCH signal on a secondary cell, SCell; determining one or more PUCCH resources at least based on a 2-bit value of a transmit power control, TPC, field of the PDCCH signal; and transmitting (S3320, S3330) the control information using the one or more determined PUCCH resources, characterized in: wherein, if a single antenna port transmission mode is configured for the PUCCH format 3, the RRC message has no further set of four PUCCH resource values for the PUCCH format 3, and the 2-bit value of the TPC field is mapped to one of the four PUCCH resource values of the first set of four PUCCH resource values for a first antenna port, and wherein, if a multi-antenna port transmission mode is configured for the PUCCH format 3, the RRC message further comprises a second set of four PUCCH resource values, and the 2-bit value of the TPC field is mapped to one of the four PUCCH resource values of the first set of four PUCCH resource values for the first antenna port and a value of a downlink assignment index, DAI, field of the PDCCH signal is mapped to one of the four PUCCH resource values of the second set of four PUCCH resource values for a second antenna port. wherein, if a single antenna port transmission mode is configured for the PUCCH format 3, the RRC message has no further set of four PUCCH resource values for the PUCCH format 3, and the 2-bit value of the TPC field is mapped to one of the four PUCCH resource values of the first set of four PUCCH resource values for a first antenna port, and wherein, if a multi-antenna port transmission mode is configured for the PUCCH format 3, the RRC message further comprises a second set of four PUCCH resource values, and the 2-bit value of the TPC field is mapped to one of the four PUCCH resource values of the first set of four PUCCH resource values for the first antenna port and a value of a downlink assignment index, DAI, field of the PDCCH signal is mapped to one of the four PUCCH resource values of the second set of four PUCCH resource values for a second antenna port.