wifi bit rate

[John Horne]

On Mon, 2012-05-21 at 17:19 -0700, JD wrote:
>
> When I take my laptop to starbucks or McDonalds hot spot,
> even when sitting outside, bitrate never is below 54mbps,
> sometime is as high as 72mb/s
> 
Hi,

Reading through your messages, you have now said two things:

1) You used an RTL card and got the same problem;
2) Using the laptop elsewhere (starbucks) and it works fine.

To me both of those tend to indicate that the WLAN card is okay, but
perhaps your router (or at least something else) is causing a problem.
The RTL card would have used a different driver than the Atheros.

You also said that the card worked fine with F14. Although the ath9k
driver will most likely have changed between F14 and F16, that wouldn't
explain why it works fine at starbucks or why the RTL had the same
problem.

I would say take a look at the router to see if anything unusual is
happening there.

I have heard before that sometimes dropping the router/card to 802.11b
or g can resolve odd problems with 802.11n cards. (Something like
'iwconfig wlan0 rate 54M') Obviously the speed will not be the best, but
possibly better than 18Mb/s :-)

Finally, if the driver really looks like a possibility, then you could
run 'modinfo ath9k' to see what options the driver takes. It may have a
debug option to cause further messages to be written to dmesg. Actually,
checking dmesg may be a good step anyway (something like 'dmesg | grep
ath').

(FYI, I have an Atheros USB card which uses the carl9170 driver. The
card is 802.11bgn, but my router is only 'b' or 'g'. I get a fairly
consistent maximum 54Mb/s :-) )




John.

-- 
John Horne, Plymouth University, UK
Tel: +44 (0)1752 587287    Fax: +44 (0)1752 587001