Well, it looks like the txpower of your wdnr3800 is limited to 17dBm because of the hardware reg-domain settings.
Kind regards, ... sent from my iPhone > Am 29.07.2015 um 10:43 schrieb Nicola von Thadden <n...@vthadden.de>: > > Hi, > > I have this strange behaviour down below, for which I also opened a > ticket because I think this should not be like that ;) > > Does anyone have an idea where the problem could originate from and how > to fix it? > > Thanks > Nico > >> On 07/29/2015 12:37 AM, OpenWrt wrote: >> #20222: 2.4Ghz limited to 50mW in DFS-ETSI >> ----------------------+---------------------------------- >> Reporter: nicoduck | Owner: developers >> Type: defect | Status: new >> Priority: normal | Milestone: Chaos Calmer (trunk) >> Component: kernel | Version: Trunk >> Keywords: wndr3800 | >> ----------------------+---------------------------------- >> I have got a Netgear WNDR 3800 running with openwrt since quite a while. >> I now upgraded to the latest version (trunk) and wanted to use WLAN within >> the regulations here in Germany but also wanted to max out the output >> power (within the regulations). >> Switching the country to Germany limits the maximum output power to 17dBm, >> although it does show as being limited on 20dBm: >> root@OpenWrt:/# iwinfo wlan0 txpower >> 0 dBm ( 1 mW) >> 1 dBm ( 1 mW) >> 2 dBm ( 1 mW) >> 3 dBm ( 1 mW) >> 4 dBm ( 2 mW) >> 5 dBm ( 3 mW) >> 6 dBm ( 3 mW) >> 7 dBm ( 5 mW) >> 8 dBm ( 6 mW) >> 9 dBm ( 7 mW) >> 10 dBm ( 10 mW) >> 11 dBm ( 12 mW) >> 12 dBm ( 15 mW) >> 13 dBm ( 19 mW) >> 14 dBm ( 25 mW) >> 15 dBm ( 31 mW) >> 16 dBm ( 39 mW) >> * 17 dBm ( 50 mW) >> 18 dBm ( 63 mW) >> 19 dBm ( 79 mW) >> 20 dBm ( 100 mW) >> >> What I did: reset the device, flash it with various builts from trunk and >> try to figure out what was going on. >> I now modified my regdb and was able to isolate the source of the problem: >> country DE: DFS-ETSI >> # entries 279004 and 280006 >> (2400 - 2483.5 @ 40), (100 mW) >> # entry 303005 >> (5150 - 5250 @ 80), (200 mW), NO-OUTDOOR, AUTO-BW >> # entries 304002 and 305002 >> (5250 - 5350 @ 80), (100 mW), NO-OUTDOOR, DFS, AUTO-BW >> # entries 308002, 309001 and 310003 >> (5470 - 5725 @ 160), (500 mW), DFS >> # 60 gHz band channels 1-4, ref: Etsi En 302 567 >> (57000 - 66000 @ 2160), (40) >> Thas does not work and has the mentioned behaviour, 2.4Ghz is limited at >> 17dBm. It also does not depend on which values are set in the regulatory >> database for the 2.4Ghz channels, anything over 17dBm will be limited to >> 17dBm. >> running "iw phy phy0 set txpower fixed 2000" gives no error but does not >> change it to 20dBm. Changing the value to anything below 17dBm works >> though. >> >> country DE: DFS-FCC >> # entries 279004 and 280006 >> (2400 - 2483.5 @ 40), (100 mW) >> # entry 303005 >> (5150 - 5250 @ 80), (200 mW), NO-OUTDOOR, AUTO-BW >> # entries 304002 and 305002 >> (5250 - 5350 @ 80), (100 mW), NO-OUTDOOR, DFS, AUTO-BW >> # entries 308002, 309001 and 310003 >> (5470 - 5725 @ 160), (500 mW), DFS >> # 60 gHz band channels 1-4, ref: Etsi En 302 567 >> (57000 - 66000 @ 2160), (40) >> >> Thad does work. The only change to the entry above is "DFS-FCC" instead of >> "DFS-ETSI". I can now select any powerlevel between 1 and 20dBm and it is >> also reported as being used: >> root@OpenWrt:/# iwinfo wlan0 txpower >> 0 dBm ( 1 mW) >> 1 dBm ( 1 mW) >> 2 dBm ( 1 mW) >> 3 dBm ( 1 mW) >> 4 dBm ( 2 mW) >> 5 dBm ( 3 mW) >> 6 dBm ( 3 mW) >> 7 dBm ( 5 mW) >> 8 dBm ( 6 mW) >> 9 dBm ( 7 mW) >> 10 dBm ( 10 mW) >> 11 dBm ( 12 mW) >> 12 dBm ( 15 mW) >> 13 dBm ( 19 mW) >> 14 dBm ( 25 mW) >> 15 dBm ( 31 mW) >> 16 dBm ( 39 mW) >> 17 dBm ( 50 mW) >> 18 dBm ( 63 mW) >> 19 dBm ( 79 mW) >> * 20 dBm ( 100 mW) >> >> >> I have no idea why but there seems to be a bug in the code parsing the DFS >> regulations, limiting 2.4Ghz to lot lower values than allowed. Changing it >> to DFS-FCC works for using the applicaple output power but does not seem >> to be in compliance which German law. >> >> Do you have an idea where the problem could be? I'm happy to try out more >> builds and future versions. >> >> Also (kind of off-topic): Do you know why 5Ghz channels 36-48 are forced >> to be 17dBm only on the WNDR3800? I found two possible explanations: >> either because of the factory calibration (is it possible to get them in a >> human readable form somehow? The hexdump is not really readable and I have >> not been able to find the code which pases them) or because these channels >> are considered as "edge-channels" and someone thought it would be safe to >> limit the power, to not disturb any other systems running on even lower >> channels. The latter explanation is kind of weird because it would make no >> sense to limit these 4 channels but no other ones. I find it especially >> strange because that is typically the job of regulatory authorities, to >> define those power levels. >> >> -- >> Ticket URL: <https://dev.openwrt.org/ticket/20222> >> OpenWrt <http://openwrt.org> >> Opensource Wireless Router Technology > _______________________________________________ > openwrt-devel mailing list > openwrt-devel@lists.openwrt.org > https://lists.openwrt.org/cgi-bin/mailman/listinfo/openwrt-devel _______________________________________________ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/cgi-bin/mailman/listinfo/openwrt-devel
