Poster: Dissecting 802.11ac performance - Why you should turn off MU-MIMO

Abstract

While the recent Wi-Fi standard 802.11ac achieves Gb/s theoretical capacity with Multi-User MIMO (MU-MIMO) technology, several studies reported that throughput of 802.11ac in practice is far from Gb/s link speed. We investigate the downlink throughput of Wi-Fi systems with commercially available 802.11ac products in multiple indoor environments to reveal the throughput of MU-MIMO system that user experiences in practice. From our experiments, Single-User MIMO (SU-MIMO) outperformed MU-MIMO at every experimental environments. We further provide analysis on our experimental results considering channel sounding overhead, user grouping, environmental impact, and transmission mode selection.