Patent ID: 8213378

Claim:
A method for assigning ACK channels comprising: dividing reserved ACK channels into N blocks, the N being a positive non-zero integer; assigning each of a plurality of N downlink sub-frames with a mapping label d, each mapping label corresponding to one block, the d being a positive integer greater than or equal to zero; dividing each block into a plurality of sub-blocks; assigning each sub-block with a sub-block label m according to a control channel element (CCE) label n CCE in the downlink sub-frame by selecting a value of the m to satisfy INTEGER(N CCE,m /K)×K≦n CCE ≦INTEGER(N CCE,m+1 /K)×K−1, the m being a positive integer greater than or equal to zero, the K being a positive non-zero integer, the N CCE,m representing the number of CCEs in the downlink sub-frame when n is equal to m, the N CCE,m+ 1 representing the number of CCEs in the downlink sub-frame when n is equal to m+1, the n being the number of symbols occupied by a physical downlink control channel (PDCCH); and assigning the ACK channels to the downlink sub-frames for acknowledging the downlink sub-frames according to a sequence of increasing the mapping label d first and then increasing the sub-block label m.