On Tue, Aug 04, 2015 at 09:55:06AM +0800, Chen-Yu Tsai wrote: > On Tue, Aug 4, 2015 at 9:26 AM, Chen-Yu Tsai <wens at csie.org> wrote: > > On Tue, Aug 4, 2015 at 2:27 AM, Seth Forshee <seth.forshee at canonical.com> wrote: > >> On Thu, Jul 23, 2015 at 11:32:56AM +0800, Chen-Yu Tsai wrote: > >>> Taiwan's Ministry of Transportation and Communications revised its > >>> frequency allocation rules [1] on 2014/11/17, allowing usage of 5600 ~ > >>> 5650 MHz, previously allocated to weather radars, to U-NII applications > >>> with DFS support. > >>> > >>> Also, the technical regulations [2] show that for 5470 ~ 5725 MHz U-NII > >>> applications, the peak transmit power shall not exceed the lesser of > >>> 250 mW (slightly less than 24 dBm) or 11 dBm + 10log B, where B is the > >>> 26dB emission bandwidth in MHz. This is slightly more than 23 dBm for > >>> 20 MHz channels. > >>> > >>> This patch updates both. Also add links to the two documents into the > >>> database. > >>> > >>> [1] http://www.motc.gov.tw/websitedowndoc?file=post/201411171137330.doc&filedisplay=Table+of+radio+frequency+allocation.doc > >>> [2] http://www.ncc.gov.tw/english/show_file.aspx?table_name=news&file_sn=681 > >>> > >>> Signed-off-by: Chen-Yu Tsai <wens at csie.org> > >> > >> Sorry for the slow response to these patches. > >> > >>> --- > >>> db.txt | 10 ++++++++-- > >>> 1 file changed, 8 insertions(+), 2 deletions(-) > >>> > >>> diff --git a/db.txt b/db.txt > >>> index 982db34..5114557 100644 > >>> --- a/db.txt > >>> +++ b/db.txt > >>> @@ -1118,11 +1118,17 @@ country TT: DFS-FCC > >>> (5490 - 5730 @ 160), (24), DFS > >>> (5735 - 5835 @ 80), (30) > >>> > >>> +# Source: > >>> +# Table of Frequency Allocations of Republic of China (Taiwan) / Nov 2014: > >>> +# http://www.motc.gov.tw/websitedowndoc?file=post/201411171137330.doc&; \ > >>> +# filedisplay=Table+of+radio+frequency+allocation.doc > >>> +# LP0002 Low-power Radio-frequency Devices Technical Regulations / 28 Jun 2011: > >>> +# http://www.ncc.gov.tw/english/show_file.aspx?table_name=news&file_sn=681 > >>> +# (section 3.10.1, 4.7) > >>> country TW: DFS-JP > >>> (2402 - 2472 @ 40), (30) > >>> (5270 - 5330 @ 40), (17), DFS > >>> - (5490 - 5590 @ 80), (30), DFS > >>> - (5650 - 5710 @ 40), (30), DFS > >>> + (5470 - 5725 @ 160), (23), DFS > >> > >> Based on [2], it looks like this range requires TPC, in which case the > >> power limit should be dropped by 3 dB on account of our not supporting > >> TPC. > > > > Will fix. > > > > Is there any plan to support multiple rules per band? Such as different > > power limits with vs without TPC, or something like DFS vs indoor only? Not that I know of. Currently the binary database format is a constraint on doing anything like that. > BTW, this band has the exact same restrictions as the US, as specified > by the FCC. The relevant rules were added in > > f894543 wireless-regdb: Add back regulatory rules for US > > and expanded to cover the whole band in > > 3c61549 wireless-regdb: Update 5GHz rules for US > > These show the power limit at 23 dBm as well. Any comments on this? Good question. Afaict this probably originates with commit 31dc1c5e which defines the limit for 5250-5330 MHz in the US, then using the same limit for the 5490-5730 MHz rule seemed logical. The 5250-5330 MHz rule came from QCA then. Adding Jouni to the Cc to see if he can help clarify how they arrived at 23 dBm. Hmm, I see now that 15.407(h)(1) says that TPC is not required for systems with an EIRP of less than 500 mW. In that case I guess maybe we don't need to drop the power limit by 3 dB, so in light of that 23 dBm does make sense. The documents you linked to say the same, seemingly word-for-word, so in all likelihood 23 dBm is actually okay. Thanks, Seth
