A base station receives data frames from a mobile station and selectively
gates a physical layer radio channel to provide ACK and NACK indications
responsive to the receipt of the data frames from the mobile station. The
physical layer radio channel is gated on to provide one of an ACK and a
NACK indication to the mobile station, and is gated off to provide the
other one of the ACK and NACK indications to the mobile station.