AP Power Settings

For the access points (in this case specifically the AP6 Pro), the power for the ap during operation is shown as dBm EIRP.

If using auto power or high power & UNII-1 or UNII-3 channels (non DFS), the maximum power allotted (or at least shown) on the ap is 30 dBm EIRP.

If using any UNII-2x channels (DFS) & auto power or high power, the maximum power allotted (or at least shown) on the ap is 24 dBm EIRP.

When setting power manually, the default empty field shows dBm EIRP.

For the UNII1/3 channels, I get the calculation of 30 dBm EIRP, which in theory is 30-4 (antenna gain) = 26 dBm max power (based on spec sheet for AP6 Pro).

How does the DFS channel power calculate? Since the ap shows 24 dBm EIRP at high power, that would mean the ap is only doing 20dBm radio, exclusive of the 4 dBm antenna gain?

Or am I doing math wrong in the wee hours of the morning?

I’m trying to calculate power settings, i.e., if I set power at 18 dBm EIRP (manual settings), using DFS channels, does that mean the radio power is only 14 dBm?

@carrottspc If it is reporting 24 dBm EIRP, and it is 4x4, then yes, it would be transmitting at 18 dBm at the antenna ports, and then combining to make 24 dBm EIRP. If it’s showing 30 dBm EIRP, then it would be 24 dBm power at each individual port.

Is there a way (via command line) to see the actual radio power on an AP?

Yes, iw dev would show this info. You can also use iw reg get to check regulatory limitations.

How does the calculation look like for 2.4 GHz and a 2x2 layout @Alta-Jeff ?
If the net value should be 9 dBm, what would be the EIRP value to set manually?
Thanks.

The manual setting is combined setting at the antenna port, so if you want 9 dBm EIRP, you should set it to 6.

Got it - and confirmed by checking with iw dev

Thanks @Alta-Jeff :+1:

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