EESM for IEEE 802.16e: WiMaX

For Link Level interfacing packet switched simulation adopt the AVI (actual value interface) approach for mapping the computed SNR to the Block Error Rate (BLER) Statistics. However in OFDM based system the BLER is invariant within Radio transport channel due to fading channel and adjutant bit carriers mapping, rendering the A VI to be inaccurate. Due to large variability of the channel in frequency domain, two links with same average SNR can experience drastically different performance, thus making it difficult to accurately predict the instantaneous link performance such as Frame Error Rate (FER). To overcome this problem with AVI the EESM has been used as a low complexity approach. In this paper the feasibility of EESM as an abstraction method is investigated, and then calibrated and evaluated for Link Level Interface in WiMax System IEEE802.16e.This methods is then extended to handle more advanced link enhancement such as Alamouti encoding. The Exp-ESM method has better accuracy than the existing link error methods, and preferred link error predictor for system simulator.