Written by François Vergès

Channel availability in the 5GHz spectrum space is a hot subject right now. It is so, mainly because of the new 802.11ac standard that allows the use of channel width up to 160MHz (for 802.11ac wave 2). Commonly 40MHz and 80MHz channels are mainly used, if possible.

As a Network Engineer, it is then important to know how many channels are available so you can design your wireless network accordingly. The more channels available you have, the better it is. It allows you to avoid CCI (or co-channel interference) which are deadly to any Wi-Fi network.

I found it pretty easy to find the information about 5GHz channels availability in the US. However, it’s very hard to find the same information for Canada. US telecommunications are regulated by the FCC (Federal Communication Commission). In Canada, IC (Industry Canada) is responsible for administering the technical standards and certification of equipment, managing the radio spectrum and the allocation of frequencies. So I dug into the IC’s official documents and finally found the useful information I am about to share with you!

Here are the details about the channels available in the 5GHz spectrum space in Canada :

Canadian Weather Radar operates in the 5600-5650 MHz band (Channel 120, 124 and 128). Industry Canada recommends that no equipment operate in this band, or interference to weather radar will result. In practical, no Wi-Fi operations are permitted on these channels.

What about DFS? DFS (Dynamic Frequency Selection) is a mechanism that allows wireless LANs to coexist with radar systems. It automatically selects a frequency that does not interfere with the radar systems. In Canada, any Wi-Fi devices operating on the channels 52-64, 100-116 and 132-140  have to employ a DFS radar detection mechanism. The use of DFS while implementing a Wi-Fi network is the choice of the Engineer. It allows you to use more channels for sure, however, the frequency change might bring some instability in the network. Moreover, the client devices  are not always certified for DFS band operation which is the case for many portable devices. Therefore, many engineers prefer implementing their network without the use of these "DFS" channels.

The following chart puts the results in perspective illustrating the 5GHz channels with the DFS and Weather Radar restrictions:

This following table  compares the channel availability in the 5GHz band in Canada  with the rest of the world (without the use of DFS):

So channel availability in the 5GHz band in Canada happens to be the same as in the USA. The difference between the 2 countries occurs at the maximum power and EIRP level.

Written by François Vergès


Source : Document from Industry Canada : “RSS-210 - Licence-exempt Radio Apparatus (All Frequency Bands): Category I Equipment”  Annex 9 - Local Area Network Devices