Subject: Re: 802.11 Transmit power control
To: None <>
From: Dheeraj Reddy <>
List: tech-net
Date: 10/31/2004 15:36:54
On Sun, Oct 31, 2004 at 02:28:22PM -0600, David Young wrote:

> > 
> > I still see an issue with it: if the driver *knows* what are the correct
> > units, why shouldn't it provide that information to userland, instead of
> > requiring me to calibrate the card?
> What with manufacturing variation, aging components, and the variety of
> power amps, how does a driver know the correct units?  I feel fairly
> certain that there is not a driver in NetBSD that can tell us with
> what its transmit power units are with the certainty we need for, say,
> complying with wireless regulations.

We could standardize and do all driver-independent calculations in mW
and let all drivers expect to be passed mW and then they could act
according to the units which the respective firmware/card expects (
converting mW to dB or any other unitless factor that they think is
appropriate) ? Of course, I am ssuming here that the device documentaion
contains relevant information about units.

It is better to be silent and be thought a fool than to speak and remove
all doubt