I like to use channel 149. Can someone with this hardware and operating in the USA tell me if the transmit power for this channel is capped to 23 mW?
I don't have this hardware but if someone with it replies, you can get this with: iw phy phy1 info
Replace phy1 with phy0 if the output is 2.4 GHz.
For reference, my xiaomi redmi ax6000:
# iw phy phy1 info
...
Frequencies:
* 5180.0 MHz [36] (23.0 dBm)
* 5200.0 MHz [40] (23.0 dBm)
* 5220.0 MHz [44] (23.0 dBm)
* 5240.0 MHz [48] (23.0 dBm)
* 5260.0 MHz [52] (24.0 dBm) (radar detection)
* 5280.0 MHz [56] (24.0 dBm) (radar detection)
* 5300.0 MHz [60] (24.0 dBm) (radar detection)
* 5320.0 MHz [64] (24.0 dBm) (radar detection)
* 5500.0 MHz [100] (24.0 dBm) (radar detection)
* 5520.0 MHz [104] (24.0 dBm) (radar detection)
* 5540.0 MHz [108] (24.0 dBm) (radar detection)
* 5560.0 MHz [112] (24.0 dBm) (radar detection)
* 5580.0 MHz [116] (24.0 dBm) (radar detection)
* 5600.0 MHz [120] (24.0 dBm) (radar detection)
* 5620.0 MHz [124] (24.0 dBm) (radar detection)
* 5640.0 MHz [128] (24.0 dBm) (radar detection)
* 5660.0 MHz [132] (24.0 dBm) (radar detection)
* 5680.0 MHz [136] (24.0 dBm) (radar detection)
* 5700.0 MHz [140] (24.0 dBm) (radar detection)
* 5720.0 MHz [144] (24.0 dBm) (radar detection)
* 5745.0 MHz [149] (30.0 dBm)
* 5765.0 MHz [153] (30.0 dBm)
* 5785.0 MHz [157] (30.0 dBm)
* 5805.0 MHz [161] (30.0 dBm)
* 5825.0 MHz [165] (30.0 dBm)
* 5845.0 MHz [169] (27.0 dBm) (no IR)
* 5865.0 MHz [173] (27.0 dBm) (no IR)
* 5885.0 MHz [177] (27.0 dBm) (no IR)
Run iw phy and show the part about channels 149-177 (8 channels for 160MHz channel) , yes, linux regulatory data are tailored for least common denominator permitted, ie in US you are kind of permitted very high power transmissions as AP, but Linux regdb uses lesser client configuration.
To confirm, you set your country setting to US?
OpenWrt supports AP txpower up to 30 dBm on channel 149 (and the rest of UNII-3) in the US; however, OpenWrt does restrict channels 36-48 (UNII-1) to 23 dBm, because that is what the linux wireless-regdb does.
The linux wireless-regdb database format cannot distinguish between client mode and AP mode txpower limits, so it limits txpower to the lower of client or AP mode. The FCC allows 30 dBm txpower in the US for AP’s in UNII-1, but restricts clients to 24 dBm in UNII-1. The FCC UNII-1 client txpower limit is 250 mW, which is 24 dBm. Unfortunately, 250 mW was incorrectly implemented in 2015 as 23 dBm (200 mW) for UNII-1 by the wireless-regdb maintainers and this has not been corrected to 24 dBm since. Fortunately, they at least got 250 mW = 24 dBm correct for UNII-2.
At the same time they have distinction between indoor and outdoor where outdoor devices are like one in thousands or so...
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