Methods for efficiently controlling the retransmission of data units in a wireless
telecommunication system, wherein mul tiple complementary feedback mechanisms are
used to con trol retransmission. A receiver attempts to decode each received data unit. If a
data unit is successfully decoded, the receiver transmits positive feedback to the transmitter;
if a data unit is not successfully decoded, the receiver transmits negative feedback to the
transmitter. In all cases, the trans mitter employs at least first and second feedback …