10-09-2012 01:05 PM
I have a number of AP-135's in the UK, that are showing their MAX EIRP as 15.5 for the 2.4ghz radio on the controller. My understanding is that for the UK, the max EIRP is 20dBm, so I'm curious as to why these AP's MAX is 15.5
Can anyone explain ?
10-10-2012 07:14 AM
Due to (radio specific) out-of-band and band-edge emissions, there's typically a need to apply additional power restrictions in addition to the well-known and generic in-band power limit of 20dBm. Radios do not behave ideally, and will emit amount of (unwanted) energy outside of the WiFi bands. These energy levels need to be below well defined levels to meet regulatory rules (in this case ETSI), and in order to achieve that, the maximum radio power level may need to be reduced below the 20dBm level.
When the AP-135 was first released, the initial regulatory tests resulted in a (conservative) limit in the 2.4GHz band of 15.5dBm for ETSI countries. Later SW tweaks and updated tests, allow us to increase this to 19.5dBm.
The new regulatory limits will be implemented in AOS 6.2 (and supposedly in 5.0 and 6.1 patches as well).
10-10-2012 07:36 AM
That's interesting, thanks for the information.
I'm currently running 18.104.22.168. Is there a recommended release of code currently available that increases the EIRP to 19.5 ?