What is HS-DPCCH (High speed dedicated control channel)?

The HS-DPCCH conveys uplink feedback signalling related to downlink HS-DSCH transmission. This feedback signalling comprises Hybrid-ARQ Acknowledgement and Channel Quality Indication. The HS-DPCCH data is separated so that the HARQ acknowledgement is communicated in the first slot of the sub frame while the channel quality indication is transmitted in the rest slot.