Improved MIMO-OFDM scheme for the next generation WLAN

The research and application of wireless local area networks (WLAN) technology are in a stage of rapid development. It has been one of research focuses of the wireless communications field. Through the use of enhanced single-user (SU)/multi-user (MU) multiple input multiple output (MIMO) — orthogonal frequency division multiplexing (OFDM) technology, the next generation WLAN IEEE 802.11ac dramatically increases the throughput. An improved MIMO-OFDM scheme based on modulation diversity is proposed for the next generation WLAN. It uses two-dimensional modulation diversity to the current IEEE 802.11ac transmission scheme. Through the space-time-frequency component inter-leaver and the rotational modulation, the proposed scheme exhibits high spectral efficiency and low error rate in fading channels. The simulation results show that the proposed scheme significantly outperforms the SU/MU MIMO-OFDM scheme in the current IEEE 802.11ac standard, which is up to 5 dB.