Evaluation of the contribution of transmit beamforming to the performance of IEEE 802.11ac WLANs

Abstract

Transmit beamforming in MIMO technology is employed to improve receiver SNR. It was added to 802.11n WLAN as an optional feature but not implemented. In 802.11ac, as this technique is highly simplified and also standardized, it is foreseen as a major contributor in improving performance and is expected to be extensively used in 802.11ac devices. In this paper, this feature is studied in depth through simulations in MATLAB and the performance improvement is measured (using parameters like received power, EVM, and constellation diagrams) comparing the results to another MIMO mechanism—Spatial Expansion.