wireless-regdb: Cambodia (KH) entry omits TRC-approved 5725-5850 MHz WLAN band

Hi,

I am reporting an apparent omission in the Cambodia (KH) regulatory
database entry.

The current wireless-regdb KH entry is:

country KH: DFS-ETSI
        (2402 - 2482 @ 40), (20)
        (5170 - 5250 @ 80), (20), AUTO-BW
        (5250 - 5330 @ 80), (20), DFS, AUTO-BW
        (5490 - 5710 @ 160), (27), DFS

There is no rule covering the 5725-5850 MHz WLAN band.

However, the Telecommunication Regulator of Cambodia issued Type
Approval Certificate RF-TA-2022-1104 in 2022 for the Astronautics
AFS6460 Connectivity Module.

The certificate explicitly lists these WLAN Tx/Rx ranges:

    2400 - 2483.5 MHz
    5150 - 5350 MHz
    5470 - 5725 MHz
    5725 - 5850 MHz

Source:
https://www.astronautics.com/wp-content/uploads/2022/11/Cambodia-RadioCertificate-AFS6460.pdf

I encountered this as a real interoperability failure rather than by
auditing db.txt.

An ISP-supplied Huawei HG8145V5 access point in Phnom Penh operates on
5745 MHz (channel 149) and advertises a Country Information Element of
KH.

On Ubuntu 24.04.5, Linux 6.8.0-139-generic, using the in-kernel rtw88
driver with an RTL8821CE client, the sequence is reproducible:

    CTRL-EVENT-REGDOM-CHANGE init=COUNTRY_IE type=COUNTRY alpha2=KH
    CTRL-EVENT-CONNECTED
    ~5 seconds later:
        nl80211: kernel reports: Channel is disabled
    ~55 seconds later:
        CTRL-EVENT-DISCONNECTED reason=3 locally_generated=1
        CTRL-EVENT-REGDOM-CHANGE init=CORE type=WORLD

The client then reconnects, receives the KH Country IE again, and the
cycle repeats approximately once per minute.

For example:

    10:10:18 COUNTRY_IE alpha2=KH
    10:10:18 CONNECTED
    10:10:23 Channel is disabled
    10:11:18 DISCONNECTED reason=3 locally_generated=1
    10:11:18 REGDOM WORLD

    10:11:23 COUNTRY_IE alpha2=KH
    10:11:23 CONNECTED
    10:11:28 Channel is disabled

Channel 149 at 5745 MHz falls within the 5725-5850 MHz WLAN range
explicitly listed by the 2022 TRC Type Approval Certificate.

I am happy to prepare and submit the corresponding db.txt patch.

The certificate establishes the permitted WLAN frequency range, but it
does not state a general Cambodian maximum EIRP for that range, so I
have deliberately not guessed a power limit for the regulatory
database entry.

If there is an existing convention or source used for the KH power
limits, I can incorporate that into the patch.

Signed-off-by: Arttu Pitou At

Arttu Pitou At - អាតពិទូ
Edu | AI & Cloud Architecture | DevOps | Cybersecurity
Phnom Penh, Cambodia
Website: https://working-draft.org