A method and apparatus for time-based fast positive acknowledgement
(ACK)/negative acknowledgement (NACK) reporting (FANR) operation with
enhanced general packet radio service 2 uplink (HUGE) are disclosed. A
wireless transmit/receive unit (WTRU) configures downlink FANR operation
and EGPRS-2 mode uplink transmission not to be in conflict. A modulation
and coding scheme (MCS) for the EGPRS-2 mode may be limited to an MCS
containing at most two RLC data blocks. Alternatively, three or more
piggybacked ACK/NACK (PAN) bits may be used for a time-based FANR
operation if an EGPRS-2 mode is configured. Alternatively, at least one
PAN bit may indicate an ACK/NACK for a group of RLC data blocks. The
number of PAN bits for a time-based FANR operation may be configured by
the network. The downlink FANR operation may be dynamically switched
between time-based and SSN-based.