info_i_25x25.png See important information about Ubiquiti Devices and KRACK Vulnerability in this article. We will update this document as more information becomes available.

airMAX - airOS 7 Best Channel Width

If you're new in airMax world, we highly recommend you to first read this article that explains how to select the best frequency and channel width for your outdoor links. 

Our airMax AC products follow the same basic rules, but there are some tips that you should know to squeeze every last Mb of your wireless link. 

What channel width should I use?

Narrow channels (equal or narrower than 20MHz) offer better radio sensitivity (and better SNR), less susceptibility to noise, thus better reliability, but "lower theoretical throughput". I emphasise "lower theoretical throughput", cause even that they have less bandwidth available, which in theory reduces maximum throughput, in most cases the highest SNR level helps to achieve higher data rates than wider channels, and higher and more stable performance. 

However, in 802.11ac these channels will be only negotiate up to 11ac MCS8 (2 spatial streams) data rates, which could be an important factor if you need the highest throughput and your link has a very high signal strength. 

Ideal for video surveillance, VOIP and WISPs offering medium-speed plans using PtMp systems.

 

Medium channels (between 30MHz and 50MHz) probably the best choice for most cases, where you need very-high throughput and area's interference level is low. It's usually a good alternative for PtP networks and offer a balanced option between narrow and wide channels. 

Note: 30MHz channels only support 11ac MCS8 (2 spatial streams) rates. On the other hand 40MHz and 50MHz channels support up to 11ac MCS9 (2 spatial streams) data rates.

Ideal for high-performance PtP links, high-speed PtMp networks.

 

Wide channels (60MHz and 80MHz) offer the ultimate throughput experience, it supports up to 11ac MCS9 data rates and throughput over 450Mbps. Unfortunately, these channels are very susceptible to interference because of the bandwidth used. They are only recommended when you have a very high signal strength and low interference (you can view how clean the RF spectrum is in your area using airView*). 

Ideal for highest-performance PtP links. Not recommended for PtMp networks.

 

Responsible use of spectrum: airMax AC (and airMax M) devices use unlicensed band, which is shared by all users in the 5GHz. Your interference could affect other users, in order to reduce the impact (and increase your network reliability) we highly recommend you to use narrow channels in situations where you don't need the highest throughput, for example for most video surveillance systems a 10MHz channel is more than enough to stream full 1080p video.

 

Note: depending on the country where you are there could be certain EIRP limits for certain frequencies and channel widths.

 

*Our airView is currently only available in airMax M (802.11n) devices. All airMax AC devices will support it in future firmware versions.