blob: e480a7e16082abe2eac6b6b3a1d29b8934a56a5e [file] [log] [blame]
developera11349d2022-06-02 01:06:38 +08001From 888da5f48030e45ce14f43a2bf7be07ec79b60d4 Mon Sep 17 00:00:00 2001
2From: Dennis Bland <dennis@dbperformance.com>
3Date: Wed, 20 Apr 2022 20:56:38 -0600
4Subject: [PATCH 2/5] Regulatory update for 6 GHz operation in United States
5 (US)
6
7With the 6 GHz band (U-NII-5, U-NII-6, U-NII-7, U-NII-8) in USA, the FCC
8introduces the concept of a fixed PSD (Power Spectral Density) for all
9supported 6 GHz channel widths for LPI (Low Power Indoor) environments.
10Wider channel widths have a higher noise floor, therefore specifying a
11fixed PSD allows wider channels to operate at a higher EIRP to maintain
12the same S/N ratio as smaller channel widths.
13
14While the 6 GHz specification also allows a "Standard" power mode with
15higher EIRP and PSD limits, these devices are also required to employ
16AFC (Automatic Frequency Coordination) which normally requires GNSS.
17Currently there is no way to specify different EIRP and PSD levels for
18APC and non-APC devices. Therefore, only LPI mode is considered here.
19
20LPI requires non-client (AP) devices to have a maximum PSD of 5 dBm/MHz
21and a maximum EIRP of 30 dBm. LPI requires client (STA) devices to have
22a maximum PSD of -1 dBm/MHz. The maximum channel width is 320 MHz.
23
24The following equation is used to calculate the EIRP from the PSD and
25channel width:
26
27EIRP = PSD + 10*log(channel width in MHz)
28
29Using the maximum PSD values of 5 and -1 for APs and STAs respectively,
30the EIRP in dBm for a given channel width can be calculated:
31
32Channel Width (MHz) AP STA
33------------------------------------------------
3420 18 12
3540 21 15
3680 24 18
37160 27 21
38320 31 (max 30) 25 (max 24)
39
40For channel widths up to 160 MHz, the maximum PSD is the limiting factor.
41For the 320 MHz channel width, the maximum EIRP is the limiting factor.
42
43Unfortunately, because there is currently no mechanism to specify
44different power levels for AP and STA modes, and for different channel
45widths, the smallest value has to be selected, which is 12 dBm. This
46will likely cause connectivity problems with larger channel widths until
47these additional parameters can be added.
48
496 GHz operation on oil platforms, vehicles, boats, trains, and drones is
50prohibited except on commercial aircraft above 10,000 feet altitude.
51An IR (Initiate Radiation) restriction is mentioned in the 6 GHz
52specification.
53
54Signed-off-by: Dennis Bland <dennis@dbperformance.com>
55Signed-off-by: Seth Forshee <sforshee@kernel.org>
56---
57 db.txt | 3 +++
58 1 file changed, 3 insertions(+)
59
60diff --git a/db.txt b/db.txt
61index 062ad8a..fcdc74a 100644
62--- a/db.txt
63+++ b/db.txt
64@@ -1649,6 +1649,9 @@ country US: DFS-FCC
65 # https://www.federalregister.gov/documents/2021/05/03/2021-08802/use-of-the-5850-5925-ghz-band
66 # max. 33 dBm AP @ 20MHz, 36 dBm AP @ 40Mhz+, 6 dB less for clients
67 (5850 - 5895 @ 40), (27), NO-OUTDOOR, AUTO-BW, NO-IR
68+ # 6g band
69+ # https://www.federalregister.gov/documents/2020/05/26/2020-11236/unlicensed-use-of-the-6ghz-band
70+ (5925 - 7125 @ 320), (12), NO-OUTDOOR, NO-IR
71 # 60g band
72 # reference: section IV-D https://docs.fcc.gov/public/attachments/FCC-16-89A1.pdf
73 # channels 1-6 EIRP=40dBm(43dBm peak)
74--
752.29.2
76