Multi-User Wi-Fi: OFDMA vs MU-MIMO
Wi-Fi 6 can serve several clients at once by slicing the channel (OFDMA) or by beaming through space (MU-MIMO). Drag clients around the room and see which wins, and why it depends on the traffic and where clients are.
How to use this tool controls and what to look for
Pick a method and a scenario, then drag clients around the room and see which method serves them best.
Controls to change
- Method: compare Single-user, OFDMA and MU-MIMO.
- Scenario: try IoT and voice, Downloads spread out, Downloads bunched, 1×1 devices streaming, or Mixed.
- Channel width: choose 20, 40, 80 or 160 MHz.
- AP antennas: give the AP 4 or 8 antennas.
- Clicking a client switches its: choose Traffic or Antennas (1×1 / 2×2), then click clients to change them.
- Add client: add clients, or remove them.
What to look for
- OFDMA wins with many small packets: each client gets a slice of the channel in the same transmission.
- MU-MIMO wins with large downloads, but only when clients are spread out in different directions.
- Bunch the clients together and MU-MIMO can't separate them any more.
- Check the scorecard for time, throughput and latency for each method.
About this tool
Wi-Fi 6 can serve several clients in one transmission in two different ways: OFDMA gives each client a slice of the channel's frequencies, and MU-MIMO gives each client its own beam through the whole channel. This simulator lets you place clients and change the traffic and channel width to see which wins, and why it depends on the traffic and on where the clients are.
What you'll learn
- How OFDMA divides a channel into resource units (26 to 996 tones)
- How MU-MIMO separates clients by direction
- Why OFDMA suits many small packets and MU-MIMO suits large downloads
- Why MU-MIMO needs clients that are spread out
Common questions
What is the difference between OFDMA and MU-MIMO?
OFDMA splits the frequencies of a channel between clients; MU-MIMO sends different streams to different clients over the whole channel at once, using beamforming.
Which is better, OFDMA or MU-MIMO?
It depends: OFDMA helps most with many clients sending small amounts of data, MU-MIMO with a few clients downloading a lot from different directions.
What resource units are there on a 20 MHz channel?
26-, 52-, 106- and 242-tone RUs, so a 20 MHz channel can be split between up to nine clients.
Free for private and educational use. This interactive model is a simplified teaching aid and may contain mistakes. It is provided as is, without warranty. Use it to understand the concepts, not as a substitute for a site survey, vendor documentation or professional design advice.