New DFS channels unlocked: 120, 124, 128

For years, channels 120, 124 and 128 were off-limits in Canada. They sit in the 5600–5650 MHz range, right where Environment Canada operates weather radar. Any Wi-Fi signal in that range risked interfering with radar systems used for meteorology and aviation safety. As a result, ISED simply blocked them.

With RSS-247 Issue 4 (July 2025), that restriction has been removed. Channels 120, 124 and 128 are now fully available for Wi-Fi in Canada.

What Has Changed?

ISED officially opened the 5600-5650 MHz range in RSS-247 Issue 4, Section 6.2.3. This adds 50 MHz of new spectrum to the 5470-5725 MHz band.

Chart of the 5 GHz channels available in Canada under ISED RSS-247, July 2025. It spans 5150 to 5895 MHz across four bands and shows 28 channels at 20 MHz, 14 at 40 MHz, 7 at 80 MHz and 3 at 160 MHz, with the centre frequency of each.

Download the 5 GHz channels in Canada (PDF, 61 kB)

These channels were not just restricted, they were completely excluded from the previous version of RSS-247. They are now included with the same rules as the rest of the 5470-5725 MHz band.

Regulations for These Channels

Channels 120, 124 and 128 fall in the 5470-5725 MHz band. The rules are defined in RSS-247 Issue 4, Section 7.3.3:

DFS (Dynamic Frequency Selection) is required. The AP must detect radar signals and move to a different channel if radar is detected. This is mandatory, not optional.
Max conducted power: 250 mW (or 11 + 10log₁₀B dBm).
Max EIRP: 1 W (or 17 + 10log₁₀B dBm).
Max EIRP spectral density: 11 dBm/MHz.
TPC (Transmit Power Control) required if max EIRP exceeds 500 mW.
No license required.

In short: same rules as the other 5470-5725 MHz channels (100, 104, 108, 112, 116). If your equipment already does DFS on those channels, it can do the same on 120, 124 and 128.

What This Means for Wi-Fi Designs

Adding three new 20 MHz channels to the 5470-5725 MHz band is meaningful.

The addition of these three channels completes the 5470-5725 MHz band and enables a new 80 MHz channel centered at 5610 MHz (channels 116, 120, 124, 128). This was not possible before.

Should You Use Them Now?

Legally, yes. Practically, proceed with caution.

Not all client devices support channels 120, 124 and 128 yet. Some older or lower-end devices may not include them in their channel scan, which means they would simply not connect if an AP is transmitting on one of those channels. Until client support is widespread, I recommend not deploying these channels in production enterprise networks. Monitor vendor support and revisit once the ecosystem catches up.

For lab environments, testing, or new greenfield deployments with controlled client devices, these channels are worth exploring.

The Rest of the Series

This post is the third one from the series. Here are links to the other ones:

Resources

All the information in this post is based on the official ISED documents. You can find them here:

RSS-247 (Issue 4, July 2025) – Digital Transmission Systems, Local Area Network Devices, and Point-to-Point and Point-to-Multipoint Equipment Operating in Licence-Exempt Frequency Bands