Datasheet

802.11ac Technology
Initial 802.11ac Wave 1 SU‑MIMO (Single‑User, Multiple Input,
Multiple Output) technology allows an earlier‑generation AP, such as
the UniFi AC Pro AP, to communicate with only one client at atime.
802.11ac Wave 2 MU‑MIMO (Multi‑User, Multiple Input, Multiple
Output) technology allows a Wave 2 AP, such as the UDM, to
communicate with multiple clients at the same time – signicantly
increasing multi‑user throughput and overall user experience. The
following describes a 4‑client scenario:
MU-MIMO Assuming the same conditions, a Wave 2 AP
provides up to 75% improvement
1
overall over a Wave1 AP. This
improvement increases wireless performance and/or serves more
clients at the same performance level.
4x4 Spatial Streams At any single time, a Wave 2 AP can
communicate with the following MU‑MIMO clients:
• four 1x1 clients
• two 2x2 clients
• one 2x2 client and two 1x1 clients
• one 3x3 client and one 1x1 client
A 4x4 Wave 2 AP delivers up to 33% greater performance
1
than a
Wave 1 AP that is 3x3 in both radio bands.
Real-World Performance Combining the performance increases
from MU‑MIMO technology and the use of 4x4 spatial streams, the
UDM delivers up to 125% greater performance
1
than a typical Wave
1 AP.
Client Compatibility For optimal performance, use MU‑MIMO
clients. SU‑MIMO clients will also benet and gain up to 10‑20%
greater performance when used with the UDM.
 Actual performance values may vary depending on environmental and installation conditions.
Single-Client Aggregate Throughput
56%
Improvement
0
50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800
850
900
950
Mbps
600 Mbps
940 Mbps
UniFi AC Pro AP
UniFi Dream Machine
10-Client Aggregate Throughput
238%
Improvement
130 Mbps
UniFi AC Pro AP
UniFi Dream Machine
440 Mbps
0
50 100 150 200 250 300 350 400 450 Mbps
100-Client Aggregate Throughput
900%
Improvement
UniFi AC Pro AP
UniFi Dream Machine
300 Mbps
0
50 100 150 200 250 300 350 400 450 Mbps
30*
* Mbps
Throughput data based on lab tests using Veriwave trac simulator.
High-Density Scenarios
Both Wave 1 and Wave 2 APs oer 28 independent
(non‑overlapping) channels: three for the 2.4 GHz band and
twenty‑ve for the 5 GHz band, including DFS channels.
When you use the 2.4 GHz band in a high‑density location, you
encounter self‑interference and channel saturation.
When you use the 5 GHz band, you can deploy smaller cells
(coverage areas), so you can support more clients in any cell that
deploys more than one AP.
With the advantages of MU‑MIMO technology and 4x4 spatial
streams, the UDM can support more than triple the number of
users
2
than a typical Wave1 AP.
In practice, the maximum number of users the UDM can support is
limited by radio link airtime. This depends on the amount of trac
each device creates, types of devices, network conguration, and
the presence of other APs on the same channel.
Recommended Maximum Number ofUsers
70 Users
UniFi AC Pro AP
UniFi Dream Machine
0
50 100 150 200 250 300 350 400 450 500 Users
125 Users
As a theoretical maximum, the UDM supports the maximum
number of users as specied by the 802.11ac standard.
For more information about network capacity and high‑density
design, go to: ubnt.link/UniFi-UAPs-High-Density
 Actual numbers may vary depending on environmental and installation conditions.
5
DATASHEET