AP Transmit Power and Enable Power Reduction with Auto TX

[Franz1879]

Hi Guys,

I want ask you more informations about Power Setting on Meraki Wirelss APs. 

Specifically, on Wireless > Configure > Radio settings > Radio power, you have 2 Options

1. Always use 100% power

2. Enable Power Reduction

Selecting an AP you have another menu where you can choose the power setting of single AP with a fixed value or Auto.

What I understand is that if you select option 1 and leave the AP power in Auto, AP will try to use the maximum Power transmission only limited to factors specified here:

https://documentation.meraki.com/MR/Radio_Settings/Max_Radio_Power_Limitations

If you select option 2 leaving AP in Power Setting Auto, Ap will try to utilize Auto TX process to find out the best power setting.

Has anyone more informations about these setting and recommended selection?

Thanks

[MerakiDave]

Correct, if you set Tx power manually, it will override the other settings on an AP-by-AP basis. You almost never want to leave your settings to always transmit at 100% power, that would typically be 30dBm (1 full watt) which can create issues where far-away clients can hear the AP by the AP could never hear the clients because the typical mobile client device might max out at 15 or 20dBm. That can also create some odd roaming behavior or association issues. As a rule of thumb, always enable automatic power reduction, and only override with manual settings when there's a specific reason to do so, which would typically be uncovered during a site survey for example. For example, in an open area with a high density of APs, you might consider disabling every-other 2.4GHz radio to reduce 1/6/11 co-channel interference.

[Franz1879]

Hi MerakiDave, thanks for your answer. It's made the settings much clearer.

I've a last questions about it: if you leave setting to Always use 100% power (as is the default) and on AP setting Power is Auto, APs keep the power limited also to do not overlap with other AP of same network ?

Thanks

[NolanHerring]

If the global setting is set to 'Always use 100% power' and the power setting on the specific AP is set to AUTO, then it will basically always have max power.

If you change the power on the AP manually, to say 11dBm, then it will change from 100% (which varies depending on frequency being used - UNII-1 vs UNII-3 etc.) to the lower value at 11dBm.

Hard to say if you will or won't have overlap since we have no idea how you have your access points positioned.

You will want overlap, so that as you walk away from AP1, there is overlap that allows smooth roaming transition, to AP2. This kind of specific information usually requires a wireless site survey to be performed. Overlap isn't a necessarily a bad thing, as long as you have channel re-use.

Meaning AP1 is on channel 36, and AP2 is on channel 149 etc.