Does 11ac require RF planning? Would you use directional antennas and sectorized cells?
Yes, since it leverages the same 2.4GHz and 5GHz bands that were leveraged by 802.11n, you should do RF planning to properly design your AP placement and channel selections to deliver the best performance and coverage. Products like Aruba AirWave and Aruba VisualRF Plan are available to aid you in the planning process. Most customers will be best served by leveraging the integrated omni-directional antennae that are built into the AP-225, however we do support external directional or sectional antennae with the AP-224.
You should perform RF planning to minimize the channel overlap in your deployment and maximize performance. With the wider 80MHz channels, there are still 5 non-overlapping channels that can be leveraged in your deployment. If your network has a mix of 802.11ac and 802.11n Access Points then you should also consider the 802.11n APs in your planning to minimize the occurrence of when APs need to fallback to narrower channels temporarily. Fortunately the standard was designed to allow for rapid negotiation of channel width so it can automatically drop down to 40MHz or 20MHz during interference times and return to 80MHz operation when possible.
• Chris Voce, Principal Analyst, Forrester Research, Inc.