From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luis R. Rodriguez Date: Fri, 20 Nov 2009 06:44:15 -0800 Subject: [ath9k-devel] TX power control, WAS: Rate Selection problems in mixed 802.11b/802.11g IBSS In-Reply-To: <5932.17670.qm@web51409.mail.re2.yahoo.com> References: <319036.9736.qm@web51403.mail.re2.yahoo.com> <43e72e890911170907m673cac0bnf6b68c4015dae276@mail.gmail.com> <5932.17670.qm@web51409.mail.re2.yahoo.com> Message-ID: <43e72e890911200644q43a497ccxb6f9d22855c4a5ea@mail.gmail.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ath9k-devel@lists.ath9k.org On Fri, Nov 20, 2009 at 5:05 AM, Joerg Pommnitz wrote: > Luis, > I'm retracting my observation. Trying to reproduce it with the > logs you asked for did show that the ath9k node tried to increase > the tx data rate from time to time and that the signal strength > was very low. I don't quite understand this, but now I do not > think that the RC algorithm is to blame. Oh ok, good to hear thanks for the report back. > Another question popped up, however. I'm evaluating ath9k and > Atheros 802.11n cards for a project we are working on. Together > with a co-worker we did some measurements of the tx power. What > we found is, that using iwconfig to change the tx power had no > measurable effect on the tx power on the antenna port. Even if I > configured the tx power down to 1db the measured value remained > constant at 27mW. > So, tx power control seems not to be implemented in ath9k. Is this > correct and if so, will this change? It is indeed but it was just reported a couple of days ago it only takes effect after a scan. This is because we cache the tx power setting and only apply it later. See: http://wireless.kernel.org/en/users/Drivers/ath9k/bugs Luis