[PATCH] wireless-regdb: Update regulatory rules for Singapore (SG)

[PATCH] wireless-regdb: Update regulatory rules for Singapore (SG)

[Sven Eckelmann]

2.4GHz and the lower 5GHz band can now be use with up to 23dBm. But the DFS
channels in general require TPC to be usable. Only 5150 - 5250 has an
exception which allows the use of it without TPC when reducing the power to
20 dBm.

Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com>
---
Please check this twice because this is my first attempt in converting an
official regulatory document to an wireless-regdb entry.

 db.txt | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/db.txt b/db.txt
index 0bc068e..df30f37 100644
--- a/db.txt
+++ b/db.txt
@@ -1078,12 +1078,17 @@ country SE: DFS-ETSI
 	# 60 GHz band channels 1-4, ref: Etsi En 302 567
 	(57000 - 66000 @ 2160), (40)
 
+# Source
+# https://www.imda.gov.sg/~/media/imda/files/regulation%20licensing%20and%20consultations/ict%20standards/telecommunication%20standards/radio-comms/imdatssrd.pdf?la=en
+# page 12-14
+# The EIRP for 5250 – 5350 can be increased by 3dB if TPC is implemented.
 country SG: DFS-FCC
-	(2402 - 2482 @ 40), (20)
-	(5170 - 5250 @ 80), (17), AUTO-BW
-	(5250 - 5330 @ 80), (24), DFS, AUTO-BW
-	(5490 - 5730 @ 160), (24), DFS
-	(5735 - 5835 @ 80), (30)
+	(2400 - 2483.5 @ 40), (23)
+	(5150 - 5250 @ 80), (23), AUTO-BW
+	(5250 - 5350 @ 80), (20), DFS, AUTO-BW
+	# 5470 - 5725 is only allowed when TPC is implemented
+	# (5470 - 5725 @ 160), (30), DFS
+	(5725 - 5850 @ 80), (30)
 
 country SI: DFS-ETSI
 	(2402 - 2482 @ 40), (20)
-- 
2.11.0

Re: [PATCH] wireless-regdb: Update regulatory rules for Singapore (SG)

[Seth Forshee]

On Mon, Aug 07, 2017 at 10:19:50AM +0200, Sven Eckelmann wrote:
> 2.4GHz and the lower 5GHz band can now be use with up to 23dBm. But the DFS
> channels in general require TPC to be usable. Only 5150 - 5250 has an
> exception which allows the use of it without TPC when reducing the power to
> 20 dBm.
> 
> Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com>

Thanks for the patch, and apologies for the slow response. One comment
below.

> ---
> Please check this twice because this is my first attempt in converting an
> official regulatory document to an wireless-regdb entry.
> 
>  db.txt | 15 ++++++++++-----
>  1 file changed, 10 insertions(+), 5 deletions(-)
> 
> diff --git a/db.txt b/db.txt
> index 0bc068e..df30f37 100644
> --- a/db.txt
> +++ b/db.txt
> @@ -1078,12 +1078,17 @@ country SE: DFS-ETSI
>  	# 60 GHz band channels 1-4, ref: Etsi En 302 567
>  	(57000 - 66000 @ 2160), (40)
>  
> +# Source
> +# https://www.imda.gov.sg/~/media/imda/files/regulation%20licensing%20and%20consultations/ict%20standards/telecommunication%20standards/radio-comms/imdatssrd.pdf?la=en
> +# page 12-14
> +# The EIRP for 5250 – 5350 can be increased by 3dB if TPC is implemented.
>  country SG: DFS-FCC
> -	(2402 - 2482 @ 40), (20)
> -	(5170 - 5250 @ 80), (17), AUTO-BW
> -	(5250 - 5330 @ 80), (24), DFS, AUTO-BW
> -	(5490 - 5730 @ 160), (24), DFS
> -	(5735 - 5835 @ 80), (30)
> +	(2400 - 2483.5 @ 40), (23)
> +	(5150 - 5250 @ 80), (23), AUTO-BW
> +	(5250 - 5350 @ 80), (20), DFS, AUTO-BW
> +	# 5470 - 5725 is only allowed when TPC is implemented
> +	# (5470 - 5725 @ 160), (30), DFS

I'm not sure that the lack of a specific provision for operating without
TPC in this range means that it cannot be used. As I understand it, TPC
would only result in a reduction in EIRP of 3 dB, so as long as we use
a power limit of half of the maximum allowed we will be safe.

If this is incorrect I'd appreciate it if someone more knowledgable on
the topic could chime in.

Thanks,
Seth

Re: [PATCH] wireless-regdb: Update regulatory rules for Singapore (SG)

[Sven Eckelmann]

[-- Attachment #1: Type: text/plain, Size: 4802 bytes --]

On Mittwoch, 23. August 2017 15:52:40 CEST Seth Forshee wrote:
[...]
> > +# Source
> > +# https://www.imda.gov.sg/~/media/imda/files/regulation%20licensing%20and%20consultations/ict%20standards/telecommunication%20standards/radio-comms/imdatssrd.pdf?la=en
> > +# page 12-14
> > +# The EIRP for 5250 – 5350 can be increased by 3dB if TPC is implemented.
[...]
> > +	# 5470 - 5725 is only allowed when TPC is implemented
> > +	# (5470 - 5725 @ 160), (30), DFS
> 
> I'm not sure that the lack of a specific provision for operating without
> TPC in this range means that it cannot be used. As I understand it, TPC
> would only result in a reduction in EIRP of 3 dB, so as long as we use
> a power limit of half of the maximum allowed we will be safe.
> 
> If this is incorrect I'd appreciate it if someone more knowledgable on
> the topic could chime in.

I would also be happy about feedback regarding this part. But my current 
settings are based on the document [1] mentioned in this change.

Let us look at the range 5250 – 5350 on page 13. There are two entries for the 
same frequency range.

 * 28:
   - up to 200 mW
   - requires TPC for 5250 – 5350 Mhz
 * 29:
   - up to 100 mW
   - requires *no* TPC for 5250 – 5350 Mhz

This is exactly the 3(.01029995...) dB difference which you've talked about. 
Now to the frequency range 5470 - 5725 MHz on page 14. 

 * 30:
   - up to 1000 mW
   - requires TPC for 5470 - 5725 MHz

There is no extra exception rule for non-TPC mode.

Now let us check what IEEE 802.11h-2003 [2] says about TPC.

* 5.4.4.1 TPC:
  - doesn't say anything about 3dB but mentions adaption based on different 
    criteria
* 7.3.2.16 Power Capability element
  - nothing regarding 3 dB here (just allows 5 dB tolerance)
* 7.3.2.17 TPC Request element
  - only describes the element
  - nothing relevant regarding the usage
* 7.3.2.18 TPC Report element
  - only describes the element
  - nothing relevant regarding the usage
* 7.4.1.3 TPC Request frame format
  - only describes the element
  - nothing relevant regarding the usage
* 7.4.1.4 TPC Report frame format
  - only describes the element
  - nothing relevant regarding the usage
* 10.3.16 TPC request
  - nothing relevant regarding the limits
* 11.5 TPC procedures
  - refers to 11.5.4 for the power adaption
* 11.5.4 Adaptation of the transmit power
  - has some suggestions to the power reduction methods
  - doesn't go into details
  - nothing about a 3dB only reduction

Ok, where is the 3 dB then coming from? My guess is the mitigation 
requirement. This should be 3 dB as *default* value (page 59). "11.5 TPC 
procedures" says following:

"Potential methods to ensure regulations are met even if TPC is not employed
include using a transmit power that is below the legal maximum (including any 
mitigation factor).".

It informs us also in "11.5.2 Specification of regulatory and local maximum 
transmit power levels" that the mitigation factors are defined in each 
regulatory domain:

"Any calculation of the local maximum transmit power for the channel shall 
ensure the mitigation requirements for the channel in the current regulatory 
domain can be satisfied. The conservative approach is to set the local maximum 
transmit power level equal to the regulatory maximum transmit power level 
minus the mitigation requirement. However, it may be possible to satisfy the 
mitigation requirement using a higher local maximum transmit power level. A 
lower local maximum transmit power level may be used for other purposes (e.g., 
range control, reduction of interference)."

It is therefore now relevant to know how these these statements from 802.11h 
and the statements from the the Singapore document have to be combined 
correctly. My current change now assumes following strict interpretation:

 * Singapore provides a mitigation factor of 3 dB for 5250 – 5350 Mhz (see 
   table entry 28 + 29)
 * Singapore provides now mitigation factor for 5470 - 5725 MHz and requires 
   TPC

I am currently unsure whether it is now valid to say that the default 
mitigation factor would be 3 dB and thus there is an implicit table entry (let 
us call it 30b) which would be:

 * 30b:
   - up to 500 mW
   - requires *no* TPC for 5470 - 5725 MHz

Countries like AU or regions like ETSI (ETSI EN 301 893) seem to have this 
mitigation factor always specified in their rules. But Singapore is missing it 
for this specific frequency range.

Kind regards,
	Sven

[1] https://www.imda.gov.sg/~/media/imda/files/regulation%20licensing%20and%20consultations/ict%20standards/telecommunication%20standards/radio-comms/imdatssrd.pdf?la=en
[2] http://standards.ieee.org/getieee802/download/802.11h-2003.pdf

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Re: [PATCH] wireless-regdb: Update regulatory rules for Singapore (SG)

[Seth Forshee]

On Thu, Aug 24, 2017 at 09:13:42AM +0200, Sven Eckelmann wrote:
> On Mittwoch, 23. August 2017 15:52:40 CEST Seth Forshee wrote:
> [...]
> > > +# Source
> > > +# https://www.imda.gov.sg/~/media/imda/files/regulation%20licensing%20and%20consultations/ict%20standards/telecommunication%20standards/radio-comms/imdatssrd.pdf?la=en
> > > +# page 12-14
> > > +# The EIRP for 5250 – 5350 can be increased by 3dB if TPC is implemented.
> [...]
> > > +	# 5470 - 5725 is only allowed when TPC is implemented
> > > +	# (5470 - 5725 @ 160), (30), DFS
> > 
> > I'm not sure that the lack of a specific provision for operating without
> > TPC in this range means that it cannot be used. As I understand it, TPC
> > would only result in a reduction in EIRP of 3 dB, so as long as we use
> > a power limit of half of the maximum allowed we will be safe.
> > 
> > If this is incorrect I'd appreciate it if someone more knowledgable on
> > the topic could chime in.
> 
> I would also be happy about feedback regarding this part. But my current 
> settings are based on the document [1] mentioned in this change.
> 
> Let us look at the range 5250 – 5350 on page 13. There are two entries for the 
> same frequency range.
> 
>  * 28:
>    - up to 200 mW
>    - requires TPC for 5250 – 5350 Mhz
>  * 29:
>    - up to 100 mW
>    - requires *no* TPC for 5250 – 5350 Mhz
> 
> This is exactly the 3(.01029995...) dB difference which you've talked about. 
> Now to the frequency range 5470 - 5725 MHz on page 14. 
> 
>  * 30:
>    - up to 1000 mW
>    - requires TPC for 5470 - 5725 MHz
> 
> There is no extra exception rule for non-TPC mode.
> 
> Now let us check what IEEE 802.11h-2003 [2] says about TPC.

<snip detailed analysis>

> My current change now assumes following strict interpretation:
> 
>  * Singapore provides a mitigation factor of 3 dB for 5250 – 5350 Mhz (see 
>    table entry 28 + 29)
>  * Singapore provides now mitigation factor for 5470 - 5725 MHz and requires 
>    TPC
> 
> I am currently unsure whether it is now valid to say that the default 
> mitigation factor would be 3 dB and thus there is an implicit table entry (let 
> us call it 30b) which would be:
> 
>  * 30b:
>    - up to 500 mW
>    - requires *no* TPC for 5470 - 5725 MHz
> 
> Countries like AU or regions like ETSI (ETSI EN 301 893) seem to have this 
> mitigation factor always specified in their rules. But Singapore is missing it 
> for this specific frequency range.

So on the one hand I'm in agreement, it would be good to know where the
3 dB attenuation comes from and whether it's really universal. So far
it's been something I've taken on faith from folks a lot more familiar
with the subject than me.

However, it seems the same lack of information would also anyone who
does want to support TPC. The information about how much to attenuate
must either be provided on a per-regulatory-domain basis or else it must
be standardized somehow. If it's the former then it seems odd that
Singapore does not include this information.

Hopefully someone more knowledgable will chime in to help us understand
better.

Thanks,
Seth

Re: [PATCH] wireless-regdb: Update regulatory rules for Singapore (SG)

[Seth Forshee]

On Thu, Aug 24, 2017 at 11:17:44AM -0500, Seth Forshee wrote:
> On Thu, Aug 24, 2017 at 09:13:42AM +0200, Sven Eckelmann wrote:
> > On Mittwoch, 23. August 2017 15:52:40 CEST Seth Forshee wrote:
> > [...]
> > > > +# Source
> > > > +# https://www.imda.gov.sg/~/media/imda/files/regulation%20licensing%20and%20consultations/ict%20standards/telecommunication%20standards/radio-comms/imdatssrd.pdf?la=en
> > > > +# page 12-14
> > > > +# The EIRP for 5250 – 5350 can be increased by 3dB if TPC is implemented.
> > [...]
> > > > +	# 5470 - 5725 is only allowed when TPC is implemented
> > > > +	# (5470 - 5725 @ 160), (30), DFS
> > > 
> > > I'm not sure that the lack of a specific provision for operating without
> > > TPC in this range means that it cannot be used. As I understand it, TPC
> > > would only result in a reduction in EIRP of 3 dB, so as long as we use
> > > a power limit of half of the maximum allowed we will be safe.
> > > 
> > > If this is incorrect I'd appreciate it if someone more knowledgable on
> > > the topic could chime in.
> > 
> > I would also be happy about feedback regarding this part. But my current 
> > settings are based on the document [1] mentioned in this change.
> > 
> > Let us look at the range 5250 – 5350 on page 13. There are two entries for the 
> > same frequency range.
> > 
> >  * 28:
> >    - up to 200 mW
> >    - requires TPC for 5250 – 5350 Mhz
> >  * 29:
> >    - up to 100 mW
> >    - requires *no* TPC for 5250 – 5350 Mhz
> > 
> > This is exactly the 3(.01029995...) dB difference which you've talked about. 
> > Now to the frequency range 5470 - 5725 MHz on page 14. 
> > 
> >  * 30:
> >    - up to 1000 mW
> >    - requires TPC for 5470 - 5725 MHz
> > 
> > There is no extra exception rule for non-TPC mode.
> > 
> > Now let us check what IEEE 802.11h-2003 [2] says about TPC.
> 
> <snip detailed analysis>
> 
> > My current change now assumes following strict interpretation:
> > 
> >  * Singapore provides a mitigation factor of 3 dB for 5250 – 5350 Mhz (see 
> >    table entry 28 + 29)
> >  * Singapore provides now mitigation factor for 5470 - 5725 MHz and requires 
> >    TPC
> > 
> > I am currently unsure whether it is now valid to say that the default 
> > mitigation factor would be 3 dB and thus there is an implicit table entry (let 
> > us call it 30b) which would be:
> > 
> >  * 30b:
> >    - up to 500 mW
> >    - requires *no* TPC for 5470 - 5725 MHz
> > 
> > Countries like AU or regions like ETSI (ETSI EN 301 893) seem to have this 
> > mitigation factor always specified in their rules. But Singapore is missing it 
> > for this specific frequency range.
> 
> So on the one hand I'm in agreement, it would be good to know where the
> 3 dB attenuation comes from and whether it's really universal. So far
> it's been something I've taken on faith from folks a lot more familiar
> with the subject than me.
> 
> However, it seems the same lack of information would also anyone who
> does want to support TPC. The information about how much to attenuate
> must either be provided on a per-regulatory-domain basis or else it must
> be standardized somehow. If it's the former then it seems odd that
> Singapore does not include this information.
> 
> Hopefully someone more knowledgable will chime in to help us understand
> better.

I was going through old messages in my inbox and realized that we've
never done anything about this. Unless someone speaks up soon I guess
I'll play it safe apply the patch as is, with the range commented out.

Seth

Re: [PATCH] wireless-regdb: Update regulatory rules for Singapore (SG)

[Seth Forshee]

On Tue, Sep 26, 2017 at 03:54:45PM -0400, Seth Forshee wrote:
> On Thu, Aug 24, 2017 at 11:17:44AM -0500, Seth Forshee wrote:
> > On Thu, Aug 24, 2017 at 09:13:42AM +0200, Sven Eckelmann wrote:
> > > On Mittwoch, 23. August 2017 15:52:40 CEST Seth Forshee wrote:
> > > [...]
> > > > > +# Source
> > > > > +# https://www.imda.gov.sg/~/media/imda/files/regulation%20licensing%20and%20consultations/ict%20standards/telecommunication%20standards/radio-comms/imdatssrd.pdf?la=en
> > > > > +# page 12-14
> > > > > +# The EIRP for 5250 – 5350 can be increased by 3dB if TPC is implemented.
> > > [...]
> > > > > +	# 5470 - 5725 is only allowed when TPC is implemented
> > > > > +	# (5470 - 5725 @ 160), (30), DFS
> > > > 
> > > > I'm not sure that the lack of a specific provision for operating without
> > > > TPC in this range means that it cannot be used. As I understand it, TPC
> > > > would only result in a reduction in EIRP of 3 dB, so as long as we use
> > > > a power limit of half of the maximum allowed we will be safe.
> > > > 
> > > > If this is incorrect I'd appreciate it if someone more knowledgable on
> > > > the topic could chime in.
> > > 
> > > I would also be happy about feedback regarding this part. But my current 
> > > settings are based on the document [1] mentioned in this change.
> > > 
> > > Let us look at the range 5250 – 5350 on page 13. There are two entries for the 
> > > same frequency range.
> > > 
> > >  * 28:
> > >    - up to 200 mW
> > >    - requires TPC for 5250 – 5350 Mhz
> > >  * 29:
> > >    - up to 100 mW
> > >    - requires *no* TPC for 5250 – 5350 Mhz
> > > 
> > > This is exactly the 3(.01029995...) dB difference which you've talked about. 
> > > Now to the frequency range 5470 - 5725 MHz on page 14. 
> > > 
> > >  * 30:
> > >    - up to 1000 mW
> > >    - requires TPC for 5470 - 5725 MHz
> > > 
> > > There is no extra exception rule for non-TPC mode.
> > > 
> > > Now let us check what IEEE 802.11h-2003 [2] says about TPC.
> > 
> > <snip detailed analysis>
> > 
> > > My current change now assumes following strict interpretation:
> > > 
> > >  * Singapore provides a mitigation factor of 3 dB for 5250 – 5350 Mhz (see 
> > >    table entry 28 + 29)
> > >  * Singapore provides now mitigation factor for 5470 - 5725 MHz and requires 
> > >    TPC
> > > 
> > > I am currently unsure whether it is now valid to say that the default 
> > > mitigation factor would be 3 dB and thus there is an implicit table entry (let 
> > > us call it 30b) which would be:
> > > 
> > >  * 30b:
> > >    - up to 500 mW
> > >    - requires *no* TPC for 5470 - 5725 MHz
> > > 
> > > Countries like AU or regions like ETSI (ETSI EN 301 893) seem to have this 
> > > mitigation factor always specified in their rules. But Singapore is missing it 
> > > for this specific frequency range.
> > 
> > So on the one hand I'm in agreement, it would be good to know where the
> > 3 dB attenuation comes from and whether it's really universal. So far
> > it's been something I've taken on faith from folks a lot more familiar
> > with the subject than me.
> > 
> > However, it seems the same lack of information would also anyone who
> > does want to support TPC. The information about how much to attenuate
> > must either be provided on a per-regulatory-domain basis or else it must
> > be standardized somehow. If it's the former then it seems odd that
> > Singapore does not include this information.
> > 
> > Hopefully someone more knowledgable will chime in to help us understand
> > better.
> 
> I was going through old messages in my inbox and realized that we've
> never done anything about this. Unless someone speaks up soon I guess
> I'll play it safe apply the patch as is, with the range commented out.

Applied, thanks!