UNII3 on MR46 in UK

[MAzad]

Hi 

I have a client who has a high-density office environment with a lot of users and a lot of APs.

They frequently face DFS events at the site due to which APs often switch to non-DFS channels.

This results in co-channel interference because of having multiple APs on same non-DFS channels e.g channel 40 or 44.

We are exploring the option of enabling UNII3 for them - they have MR46 running on MR30.6 release.

If we enable UNII3 range (considering they are in UK), will this allow them to use those channels too?

When i see this for one of my other clients who have many smaller offices, I see their APs never choosing a channel from UNII3 range although it is selected.

Thanks,

Mariam

[mike425]

I do not have a solution, but we have some larger offices in the UK with UNII3 enabled in the channel set and I have never seen them actually been used.

[cmr]

Same here, we have UNII3 enabled on a load of CW9166s with dual 5GHz radios at a large site and indeed they never seem to select the UNII3 channels unless manually changed to them.

[Austeames]

We raised this with Meraki support a few months back and they said that the UK is part of the EU design of which isn't approved by the EU.  We weren't able to get any information if this was moving forwards or timescales.  We're now looking at 6E to help improve the Wi-Fi service.

[cmr]

You can see here that some CW9163Es have picked an UNII3 channel, but the power is very low...

 

[cmr]

The UK allows 23dBm for UNII3 and one of those APs barely sees neighbours, so not sure why it is so low?

[Paccers]

I have a hunch.. what happens if you bring your minimum target transmit power value down for the 9163E to say, 10 dBm?

[cmr]

@Paccers I have done this and will reply with results once the APs have had a bit of time to adjust.

[cmr]

No changes yet, but the two APs have different antennas:

top 9163 - CW-ANT-O1-NS omnidirectional dipole with 4/8/8 dB of gain

bottom 9163 - CW-ANT-D1-NS patch with 8/9/9 dB of gain

Therefore in UNII3 they should support 15dB and 14dB as a respective maximum.  Were you thinking that changing the min to within the antennas range might help? 

[Paccers]

Interesting, my theory was a bit out there:

• The 23 dBm outdoor UNII-3 limit set by OFCOM would be the EIRP value
• Meraki's 'Target power' values are set at the radio, not taking cable and antenna gain/loss in to account, so this value is not a target EIRP range you are setting
• The Omnidirectional and the patch antennas for the 9163E are 8/9 dBi gain each @ 5 GHz.
• Your target min. radio TxPower is 17dBm. Assuming 0dB loss from internal cabling to the antenna + 8/9 dBi gain from the antenna, your minimum EIRP would be 25 dBm - 2dB above the max. permitted EIRP (although I'm fairly sure the APs always limit max. power to never exceed regulatory limits so the theory is probably moot!)

Theory:

• AP radio TxPower being set to some default low value given min. EIRP from target power range > max. EIRP permitted

Are these lab APs? The power ranges set on all of APs listed seem really high to me personally!

[cmr]

They are my home / test lab.  The building has double skin brick walls and the total area is large so the APs are quite spread out.

I've also realised that in the UK, band C (UNII3) is only allowed to be used if you have a license and then only for fixed devices.  The licence is easy to get and cheap, but I'm going to disable those channels for the outside until/if I get a license!

[cmr]

Changing to UNII2E (UK band B) only sets the power levels to what is expected considering the different antennas: