Methods, systems and apparatus are provided for hybrid automatic repeat request (HARQ) processes. A wireless transmit/receive unit (WTRU) may receive, in a first subframe, downlink control information (DCI) including a grant for a physical downlink shared control channel (PDSCH) and an indication of physical uplink control channel (PUCCH) resources. Further, the WTRU may receive, in the first subframe, data on the PDSCH based on the grant. Also, the WTRU may generate first acknowledgement (ACK)/negative ACK (NACK) information based on the data received on the PDSCH. Accordingly, the WTRU may transmit, in the first subframe, the first ACK/NACK information in a PUCCH transmission. In an example, the first ACK/NACK information may be transmitted in a time slot in the first subframe different from a time slot in the first subframe in which the DCI is received. Also, transmitting the PUCCH transmission may have a duration of one or two symbols.