As described above, there may be multiple PUCCH formats used for transmitting the P-CSI, and they can bear different number of bits. In different subframes, the number of the cells/CSI processes/CSI subframe sets whose P-CSI need to be fed back simultaneously may be different. Accordingly, the preferable PUCCH format for transmitting the P-CSI may also be different. Herein, one preferable method may include: for one subframe, on the premise that the selected M P-CSI can be transmitted, the PUCCH format with lower bearing capability is selected as much as possible, i.e., PUCCH format 2 is selected preferably, then PUCCH format 3, and finally PUCCH format X. For PUCCH formats 2 and 3, multiple channels using such PUCCH format may be multiplexed in one PRB, so as to increase resource utilization ratio. Accordingly, a method for configuring different PUCCH formats used for transmitting P-CSI in different subframes is required. However, the above first method only supports configuring the same PUCCH format in different subframes, which restricts the link performance and the resource utilization ratio of the P-CSI.

In a second method, one PUCCH resource is allocated to each cell of the UE, including a PUCCH format and a PUCCH resource index. But the PUCCH for transmitting the P-CSI configured for each cell is not restricted to use the same PUCCH format, i.e., if N P-CSI configured in one subframe correspond to multiple cells, these P-CSI may correspond to multiple PUCCH formats and corresponding PUCCH resource indexes, e.g., PUCCH format 2, format 3, and/or format X. For the PUCCH format X, different PUCCH resources may occupy the same number or different numbers of PRBs. Herein, it is still restricted that the multiple CSI processes/CSI subframe sets of the same cell are configured with the same PUCCH format.