A terminal apparatus comprising: a reception unit (105, 101) configured to receive a physical downlink control channel, PDCCH, with downlink control information, DCI, format, a first higher layer parameter incluiding a cell specific parameter and a second higher layer parameter including a parameter of start position of a physical uplink control channel, PUCCH, resource for frequency division duplex, FDD, decode a physical downlink shared channel, PDSCH, in subframe n-k according to detection of the PDCCH, a transmission unit configured to transmit a hybrid auto repeat request - acknowledgement, HARQ-ACK, corresponding to the PDSCH in subframe n, wherein the parameter of start position of the PUCCH resource is used to indicate a start position of a PUCCH resource in a case that k is equal to 3, where the parameter of the start position of the PUCCH resource is configured according to the value of k, the cell specific parameter is used for determining the PUCCH resource for the HARQ-ACK transmission in a case that k is equal to 4, wherein the value of is equal to 3 in a case that cyclic redundancy check, CRC parity bits added to the DCI format transmitted with the PDCCH are scrambled by a cell - radio network temporary identifier, C-RNTI, and the PDCCH is detected in a UE - specific search space, USS, and the value of k is equal to 4 in a case that the CRC parity bits added to the DCI format transmitted with the PDCCH are scrambled by the C-RNTI and the PDCCH is detected in a common search space, CSS. a reception unit (105, 101) configured to receive a physical downlink control channel, PDCCH, with downlink control information, DCI, format, a first higher layer parameter incluiding a cell specific parameter and a second higher layer parameter including a parameter of start position of a physical uplink control channel, PUCCH, resource for frequency division duplex, FDD, decode a physical downlink shared channel, PDSCH, in subframe n-k according to detection of the PDCCH, receive a physical downlink control channel, PDCCH, with downlink control information, DCI, format, a first higher layer parameter incluiding a cell specific parameter and a second higher layer parameter including a parameter of start position of a physical uplink control channel, PUCCH, resource for frequency division duplex, FDD, decode a physical downlink shared channel, PDSCH, in subframe n-k according to detection of the PDCCH, a transmission unit configured to transmit a hybrid auto repeat request - acknowledgement, HARQ-ACK, corresponding to the PDSCH in subframe n, wherein the parameter of start position of the PUCCH resource is used to indicate a start position of a PUCCH resource in a case that k is equal to 3, where the parameter of the start position of the PUCCH resource is configured according to the value of k, the cell specific parameter is used for determining the PUCCH resource for the HARQ-ACK transmission in a case that k is equal to 4, wherein the value of is equal to 3 in a case that cyclic redundancy check, CRC parity bits added to the DCI format transmitted with the PDCCH are scrambled by a cell - radio network temporary identifier, C-RNTI, and the PDCCH is detected in a UE - specific search space, USS, and the value of k is equal to 4 in a case that the CRC parity bits added to the DCI format transmitted with the PDCCH are scrambled by the C-RNTI and the PDCCH is detected in a common search space, CSS.