A method and apparatus allocate acknowledgement channels in a communication network. A linking scheme is established between indices of physical hybrid automatic repeat-request indicator channels (PHICHs), and a combination of indices of control channel elements (CCEs) or indices of physical resource blocks (PRBs) and indices of demodulation reference signals (DMRSs). A scheduling grant is transmitted to a user equipment (UE) by using a plurality of CCEs. In response to receiving a data packet and a DMRS from the UE, an index of a PHICH within the plurality of PHICHs is determined based on at least one index of the CCEs used to transmit the scheduling grant or at least one index of the PRBs used to transmit the data packet, and an index of the DMRS in accordance with the linking scheme established. The BS transmits an acknowledgement signal to the UE using the PHICH indicated by the determined index.