Hi,
I recently installed openwrt on a nanostation M2 XW. With the installation of openwrt, the transmission power was limited to 20dbm against 28dbm normally. To be sure it wasn't just an interface error, I measured the signal strength with my phone. Afterwards, I reflashed the original software and saw that the power was well and truly superior. I tested different versions of openwrt and always got the same result, from the oldest available to the most recent. The regulations allows me to have up to 36dbm EIRP against currently 30 in openwrt.
How can I resolve this?
Does not help without telling country code.
What is in iw list channel maps when you set country code to US, BE , IN (without AP being active obviously)
I have set the country code to US.
That is what iw list has returned
max # scan SSIDs: 4
max scan IEs length: 2257 bytes
max # sched scan SSIDs: 0
max # match sets: 0
max # scan plans: 1
max scan plan interval: -1
max scan plan iterations: 0
Retry short limit: 7
Retry long limit: 4
Coverage class: 0 (up to 0m)
Device supports AP-side u-APSD.
Device supports T-DLS.
Available Antennas: TX 0x3 RX 0x3
Configured Antennas: TX 0x3 RX 0x3
Supported interface modes:
* IBSS
* managed
* AP
* AP/VLAN
* monitor
* mesh point
* P2P-client
* P2P-GO
* outside context of a BSS
Band 1:
Capabilities: 0x11ef
RX LDPC
HT20/HT40
SM Power Save disabled
RX HT20 SGI
RX HT40 SGI
TX STBC
RX STBC 1-stream
Max AMSDU length: 3839 bytes
DSSS/CCK HT40
Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
Minimum RX AMPDU time spacing: 8 usec (0x06)
HT TX/RX MCS rate indexes supported: 0-15
Frequencies:
* 2412 MHz [1] (22.0 dBm)
* 2417 MHz [2] (22.0 dBm)
* 2422 MHz [3] (22.0 dBm)
* 2427 MHz [4] (22.0 dBm)
* 2432 MHz [5] (22.0 dBm)
* 2437 MHz [6] (22.0 dBm)
* 2442 MHz [7] (22.0 dBm)
* 2447 MHz [8] (22.0 dBm)
* 2452 MHz [9] (22.0 dBm)
* 2457 MHz [10] (22.0 dBm)
* 2462 MHz [11] (22.0 dBm)
* 2467 MHz [12] (disabled)
* 2472 MHz [13] (disabled)
* 2484 MHz [14] (disabled)
valid interface combinations:
* #{ managed } <= 2048, #{ AP, mesh point } <= 8, #{ P2P-client, P2P-GO } <= 1, #{ IBSS } <= 1,
total <= 2048, #channels <= 1, STA/AP BI must match, radar detect widths: { 20 MHz (no HT), 20 MHz, 40 MHz }
HT Capability overrides:
* MCS: ff ff ff ff ff ff ff ff ff ff
* maximum A-MSDU length
* supported channel width
* short GI for 40 MHz
* max A-MPDU length exponent
* min MPDU start spacing
Supported extended features:
* [ RRM ]: RRM
* [ CQM_RSSI_LIST ]: multiple CQM_RSSI_THOLD records
* [ CONTROL_PORT_OVER_NL80211 ]: control port over nl80211
* [ TXQS ]: FQ-CoDel-enabled intermediate TXQs
Antenna gain 8dbi is retracted from 30dbm radiation limit. Sounds about ok?
For this kind of device, FCC rules allows for 36dbi EIRP. In this case the gain of the antenna is 10dbi. I should be allowed a transmit power of 26dbi + the gain of the antenna which would equal the 36dbi.
i have this radio is hardware limit, trust me, i love this device. about range is about driver, that's all.
You have to make your own regdb, sign and build the kernel.
https://git.kernel.org/pub/scm/linux/kernel/git/wens/wireless-regdb.git/tree/db.txt#n1923
The "this kind of device" is not marked anywhere, it can be 30dBm client at any moment.
no it cannot do 30 dbm, the only device that can do real 30 dbm or more, only some device are mikrotik.
Watts power + antenna gain dbi = regulatory radiation EIRP.
dbm is only power trasmit, not about antenna.
Not really.
simplistic table: https://www.air802.com/fcc-rules-and-regulations.html
Linux regulatory DB takes the most conservative approach, so it is clamped to everywhere permitted 30dbm radiated power -8dbm antenna gain = 22dbm electric power
On an access point you are permitted to have 36-8=28dbm electric power, achievable tweaking the regulatory database.
How can I tweak the regulatory database on openwrt ?
Will not post recipe in public forum.
I told you,even if you change the regdb,you ll not get more than 22dbm
No, it is not the hardware's limit. If it was, the original software would not be able to emit more than openwrt.
Well maybe my device is a bit different,powerbeam m2, but in the past same firmware as your device.i never checked the txpower under ubiquiti firmware.but under wrt i was never able to go over 22 dbm. Same regbd on some mikrotik devices can go at 33dbm.