[wireless-regdb] [RFC] wireless-regdb: Update rules for 2.4GHz limit Republic of Korea (KR)

Andreas Mohr andim2 at users.sf.net
Thu Sep 14 07:49:42 PDT 2017

Dear Sir / Madam,

we have initiated a WiFi SAR/RF testing/certification effort of our current device
(handheld, TI WL1271 WLAN/Bluetooth BLE module, current Linux distribution: Ubuntu 12.04 LTS, to be modernized).

During our activities with Korean KC certification body, the following request has been made (TÜV Korea):

Mail 2016-06-14:
Please keep the power limit of less than 20mW as sent in our previous e-mail (if not fulfilled, the test will be failed).
<red>Please do not send out samples before it complies to the requirement.</red>

20mW equals 13dBm.

We already successfully applied a modified signed regulatory.bin to have (and thus use) the reduced limit,
however obviously we'd strongly prefer to have an official upstream release binary which:
- where not up-to-date (e.g. older distribution base) can be custom-applied
- where already up-to-date vs. upstream implicitly does have/receive all necessary future updates
- is signed with official wireless-regdb / distro keys

We then asked for a paper trail (specs document, black-and-white dead-tree notice etc.)
in order to file a thoroughly/legitimately claimed request for conformance update of wireless-regdb
(simply due to properly knowing the root cause / explanation for this request!
Details on why this limit has been imposed, when it got required, which modulation types it applies to, ...),
however that turned out to be difficult.
We ultimately succeeded in receiving the proper reference (Korean document, available upon request)
which lists the 20mW requirement.

Also, a prior Internet search for
"dBm site:rra.go.kr" had resulted in
(4.ÀüÀÚÆÄÀÎüº¸È£´ëÃ¥¿¬±¸.pdf , a nice UTF-8 mis-transcoding of originally Korean cp949 4.체호책.pdf 4.[uCCB4 uD638 uCC45].pdf)
which appears to list device measurements, and where notably
many 802.11g values of various company device models appear to be restricted to the 13dBm (i.e., 20mW) area.

Due to other delays, this issue has not been pursued here (sorry!).
Unfortunately it looks like
wireless-regdb HEAD (9b3317bd4) does not yet have any change which would fulfill this certification requirement.

Thus, I am now proposing (RFC) the following minimum (potentially extended/documented) update.
I decided to restrict the limitation to 2.4GHz area only since
the current certification effort (and thus the limit request) is about 2.4GHz.

Thank you!

Yours sincerely

Andreas Mohr

From 0added12024197148e87633c28959334795cbd02 Mon Sep 17 00:00:00 2001
From: Andreas Mohr <andim2 at users.sf.net>
Date: Wed, 13 Sep 2017 11:51:54 +0200
Subject: [PATCH] wireless-regdb: reduce power level limit of KR (Korea)
 802.11b/g/n to the certification-requested "20mW" (13dBm).

Signed-off-by: Andreas Mohr <andim2 at users.sf.net>
 db.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/db.txt b/db.txt
index e48f9a6..97b22b0 100644
--- a/db.txt
+++ b/db.txt
@@ -668,7 +668,7 @@ country KP: DFS-JP
 	(5735 - 5815 @ 20), (30)
 country KR: DFS-JP
-	(2402 - 2482 @ 40), (20)
+	(2402 - 2482 @ 40), (13)
 	(5170 - 5250 @ 80), (20), AUTO-BW
 	(5250 - 5330 @ 80), (20), DFS, AUTO-BW
 	(5490 - 5710 @ 160), (30), DFS

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