A Link Adaptation Solution to IEEE 802.16d WMAN

IEEE 802.16d adopts HARQ (hybrid automatic retransmission request) and AMC (automatic modulation and coding) as link adaptive mechanism. This paper proposes a link adaptive solution based on a simple but effective sliding window mechanism. Also a signal constellation rearrangement strategy is present to average out reliabilities of bits carried by repeatedly transmitted symbols over retransmissions in order that the receiver can gain better performance using Chase combining