IEEE 802.11ac: On performance of lattice-reduction successive interference cancellation OFDM MIMO receivers

The challenges and issues related to the application in IEEE 802.11ac systems of lattice reduction (LR) techniques for the implementation of successive interference cancellation (SIC) receivers in single-user (SU) and multi-user (MU) orthogonal frequency division multiplexing (OFDM) multiple input multiple output (MIMO) transceivers are investigated in this paper. The shown simulation results, validated using first-order techniques, assume realistic operational conditions faced in IEEE 802.11ac wireless local area networks (WLANs), such as, temporal auto-correlation synchronization algorithm, least square (LS) MIMO channel estimation scheme, spatial-correlated and frequency selective Task Group ac (TGac) channel models. The implementation of LR Minimum Mean Squared Error (MMSE) SIC (LR MMSE-SIC) MIMO detectors with hard-decision Viterbi decoding allows dramatic power gains in relation to LR MMSE MIMO detectors in the SU scenario when the maximum number of spatial streams (SS) in 802.11ac systems is assumed. However, no noticeable power gain occurs when the operation of 802.11ac WLANs in MU environments is taken into account.