Low feedback link abstraction based on novel quality model for 802.16e based systems

This work describes the strategies to improve the channel quality indicator (CQI) for multi-state channels in 802.16e (wimax) based systems. The method includes the use of Exponential effective SNR mapping (EESM) method as part of the modulation/coding selection process and the problems associated with this technique has been studied. MI-ESM (Mutual Information based Effective SNR mapping) SNR metric has been used for link prediction. An MMIB (Mean mutual information per bit) metric is calculated and based on this BER prediction and the simulated results were compared with numerical results. The proposed approximation has been applied to HSDPA to select the best transport and resource combination (TFRC) for link adaptation.