Demo: real-time MU-MIMO channel analysis with a custom 802.11 implementation

We present a demonstration of the real-time capture and analysis of multi-user MIMO (MU-MIMO) channel state information from commercial Wi-Fi devices. Our system is built with an array of WARP v3 nodes running the Mango Communications 802.11 Reference Design, an open-source, real-time FPGA implementation of the 802.11a/g MAC and PHY. One WARP v3 node acts as an 802.11 access point (AP), which serves Internet access to client devices. The other nodes implement an array of multi-antenna 802.11 monitors. Every monitor node simultaneously receives packets transmitted by the Wi-Fi clients associated with the AP. The nodes extract MAC headers and channel estimates from each packet and offload these to a PC for analysis. All MAC, PHY, and channel analysis processes run in real time.