1. 802.11ac Deployment Overview
Margery Reed Building
University of Denver
Marcelo Lew
CHECO Spring 2014

2. 802.11ac Benefits More MIMO Antennas
Higher Modulation and Coding Schemes
“Beam forming”
Multi-user MIMO
AP can transmit at the same time to several users. For example, a 3x ac WAP can transmit to 3 different ac 1x1 clients.
Wider RF Channels
Benefit or design nightmare for high density environments???

3. 802.11n vs. 802.11ac RF channel planning (5GHz)
Because of radar communications (DFS), 13 channels are usually not used since many clients don’t support them.
802.11n supports both 20 and 40MHz wide channels.
If you use 40MHz, then there are only 4 non-overlapping channels on the 5GHz band. Not great for enterprises and university environments because of the higher density of WAPs and the need for channel re-use.

4. 802.11n vs. 802.11ac RF channel planning (5GHz) cont.
A common recommended practice is to disable 40MHz wide channels so you have 9 non-overlapping channels to use.
However, to really see the benefit of ac, you need at least a 40MHz channel width. And for even better, 80MHz channel width.
So with ac we are back at having only 4 non-overlapping channels at 40MHz width or 2 non-overlapping channels at 80MHz.

5. 802.11ac RF Channel Layout

6. RF Design Options
Design small cells (low power) to maximize channel re-use:
This will require more WAPs.
Keep in mind it is not recommended to set the transmit power on WAPs lower than 8mw if smartphones are used (low receive sensitivity).
Tests show MU-MIMO (multi user MIMO) can accommodate more users per channel, so we might not need as many channels.

7. RF Design Options Cont. Hope FCC allocates more RF bandwidth.
Go back to single channel architectures (Meru)?
Vendors are working on enhanced DFS mechanisms to split these 13 channels into smaller portions and be able to use them without restrictions.

8. Margery Reed RF Design
We designed on a 50 foot grid pattern, and adjusted locations as necessary for high density classrooms or removed areas not needed. We used Aruba AP-225s.

9. Margery Reed Design – Cont.

10. Margery Reed Design – Cont.

11. 802.11ac stats for Margery Reed 30 days of usage via AirWave Report