On SNR Statistics Involving EESM-Based Frequency Selective Feedbacks

In an orthogonal frequency division multiple access (OFDMA) system such as LTE and WiMAX, EESM provides an efficient way to estimate the link performance of a resource block/sub-channel contains a number of sub-carriers by a single value (effective SNR). In order to learn the performance of an OFDMA system involving EESM, it is of interest to investigate the statistics of effective SNR over frequency selective channels. In this paper, general expressions including the MGF and average of EESM effective SNR over arbitrary number of sub-carriers are proposed. Subsequently, the analytical result of average effective SNR over Nakagami-m fading channel is also derived. The numerical results show that the approaches are quite useful in characterizing the average effective SNR over frequency selective channels.