= Xilinx ETS 2014 Demo: Massive MIMO Wi-Fi Channel Characterization =

The Rice Argos ([http://argos.rice.edu http://argos.rice.edu]) team partnered with [http://mangocomm.com Mango Communications] to present a Massive MIMO Wi-Fi Channel Characterization demo at the Xilinx Emerging Technology Symposium 2014. This demo combines the [http://argos.rice.edu/pubs/Shepard-MobiCom13-Demo.pdf Rice Argos v2 massive MIMO testbed] with the [wiki:802.11 Mango 802.11 Reference Design] to capture and analyze channel estimates between the array and Wi-Fi clients in real-time.

== Hardware Configuration ==

The demo uses the 96-antenna Argos v2 array. The array is built around 24 quad-antenna WARP nodes, each node consisting of a [wiki:HardwareUsersGuides/WARPv3 WARP v3 kit] and [wiki:HardwareUsersGuides/FMC-RF-2X245 FMC-RF-2X245 module]. Each node in the array runs the [wiki:802.11 802.11 Reference Design] in receive-only mode. The array elements receive every Wi-Fi packet, decode the packet to identify the transmitting client, then report the client identity and the corresponding per-subcarrier channel estimates to a host PC for processing and display.

[[Image(WARP_Array_Demo_BlkDiag.png, nolink)]]

== Channel Visualizations ==

A custom OS X application on the host PC receives the wireless client and channel estimate updates from the array nodes, process these updates and displays the results in real time. The app has two real-time displays:

'''Screen 1''': Real-time plots of channel magnitudes at each array antenna. Each plot shows magnitude of 52 complex channel coefficients (one per active subcarrier).
{{{#!html
<video width="638" height="369" controls>
  <source src="http://warpproject.org/dl/misc/WARP_ArrayDemo_App_Win1.mp4" type="video/mp4" preload="none">
</video>

}}}

'''Screen 2''': Real-time plots of wireless capacities given the latest channels between selected clients and the array.
{{{#!html
<video width="638" height="369" controls>
  <source src="http://warpproject.org/dl/misc/WARP_ArrayDemo_App_Win2.mp4" type="video/mp4" preload="none">
</video>

}}}

== Handouts ==

[attachment:Xilinx_ETS_Demo_Handout.pdf?format=raw Argos Demo Handout]

[attachment:Mango_802.11_RefDes_Handout.pdf?format=raw 802.11 Reference Design]

== Resources ==
 * [wiki:802.11 Mango 802.11 Reference Design]
 * [wiki:HardwareUsersGuides/WARPv3 WARP v3 hardware]
 * [http://argos.rice.edu Rice Argos project]