[wireless-regdb] Updates for the regulatory rules for Bulgaria

Luis R. Rodriguez mcgrof at suse.com
Thu Apr 21 09:56:45 PDT 2016

On Thu, Apr 21, 2016 at 11:34:10AM -0500, Seth Forshee wrote:
> On Thu, Apr 21, 2016 at 07:12:53PM +0300, Petko Bordjukov wrote:
> > On Thu, 21 Apr 2016 17:07:21 +0300,
> > Seth Forshee wrote:
> > > This is almost certainly because these frequencies require transmit
> > > power control. We drop the TX power limits by half (i.e. 3 dB) when TPC
> > > is required on account of not supporting TPC.
> > 
> > I was under the impression that the underlying kernel infrastructure had support
> > for TPC. What I am observing is that hostapd automatically includes the Power
> > Constraint IE in beacons sent out on any channel with DFS enabled. The default
> > transmit power reduction is 3dBm.
> > 
> > This means that the TX power of any clients would be limited to 3dBm below the
> > TX power of the AP even though it's not required.
> > 
> > Would there be any merit in providing additional information regarding the TX
> > power and the target average TX power reduction for the system when TPC is
> > supported?
> I'm frankly not certain about the status of kernel support, but my
> impression was that some drivers might have some level of TPC support
> but that it's not universal. I really haven't been keeping track of it
> though.

When I looked at adding support for Linux, IIRC the status of affairs
was that it was complex, and iffy, and no one ever really implemented
it even on Windows / OSX so the adjustments were easier to make so
that's what people did.


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