Different TX Powers on same country


#1

Hi,

i have a question about TX powers.
I tried to change the option "country" on some routers and it change the TX Power correctly.
But i know there are two different limits for the EU: 20dBm on IEEE802.11b and 18dBm on IEEE802.11g/n

If i set the 'hw_mode' option to '11ng' the TX power is 20dBm but I'm afraid it is outlaw for EU countries.

Is my doubt right?
Is there something i can do to correctly set the TX power based on the IEEE option?

Thanks a lot for your attention


#2

Dear Openwrt team, nice work about firmware :smiley: This is my first post here. Just wanna know something about TX-power limit. It seems like world is divided on 2 parts about that. USA + CA / Others (FCC vs ETSI).

But many other countries normally allow EIRP up to 1000mW (30dBm) including some of countries within EU (not just few of them) . I'm from Slovenia and based on regulation here is totally legal to use all 13 channels on 2.4GHz band combined with 1000mW (30dBm) TX power to. Individually rule of countries is visible here:


https://w.wol.ph/2015/08/28/maximum-wifi-transmission-power-country/

Why not to made third group of countries and connect it with settings of 13 channels combined with EIRP power up to 30dBm? If I mention some o those countries:

  • India
  • Malaysia (500mW)
  • Taiwan
  • Slovakia
  • Slovenia
  • Lithuania
  • Estonia
  • Latvia

Sorry for my bad English.Thank you. :slight_smile:


#3

This thread is 2 years old.

The limits are set by a county's law. I'm completely lost as to why people believe that the FCC and ETSI control other nations - it's those nations who choose to follow their rules for consistency's sake.


#4

Does this help:

https://git.openwrt.org/?p=openwrt/openwrt.git;a=commit;h=69aa1c5ac002d774f6d114eb3239c5531398dd83

+       CTRY_UKRAINE = 804,

+       CTRY_URUGUAY = 858,

+       CTRY_UZBEKISTAN = 860,

+       CTRY_VENEZUELA = 862,

#5

Thank you!

You think, will be possible to adjust 25dBm + 13 (is legal here in Slovenia) channels with use of that patch? Router is TP-link TL-WR1043ND V2.1.


#6
  • The patch should already exist...
  • I see no reason you couldn't edit your own source code

Hope this helps.


#7

Your device might not be capable of that level of output, even if legal. See, for example https://apps.fcc.gov/eas/GetApplicationAttachment.html?id=2153407 or the other certification documents.


#8

@lleachii, I'm not sure if I'm able to do that. But i will try...

@jeff, that router is capable to operate at 25dBm TX power. And because 5 dBi antenna, EIRP output is 30dBm. Is visible prom prt/scr, if I adjust country to US or Canada.

But for any other country TX power decrease to 20 dBm.


#9

Do your wifi clients also support 25-30dBm power levels? For normal use it actually makes no sense to use such a high power level because most phones,laptops are using much lower power levels. I would use something around 12-15dBm but the wifi driver (mwlwifi)of my device is bugged and is sending at full power all the time. :expressionless:


#10

The PA chips are designed for 18 to 20 dBm. Trying to push them beyond that rated power would cause signal distortion and poor performance.
http://www.skyworksinc.com/Product/1654/SE2574BL-R


#11

Also increasing power consumption and heating up the router.