Prediction of hybrid-ARQ based on mutual information model for LDPC coded OFDM system

An accurate and simple link quality model is of utmost importance in link adaptation (LA) design. Our previous work in has verified the good accuracy of the mutual information (MI) model for rate compatible (RC) LDPC coded OFDM system. In this paper, the MI model is used to predict the retransmission length T of two hybrid ARQ schemes, partial chase combining (PCC) and incremental redundancy (IR). Simulation results verified that the one time retransmission satisfied a certain target BELR with predicted T, i.e. the needed minimum retransmission length. Thus the MI model can serve as an accurate prediction model for high spectrum efficiency hybrid ARQ design of LDPC coded OFDM system.