[USRP-users] problem with loopbacks when using USRP

mleech at ripnet.com mleech at ripnet.com
Tue Jul 28 11:51:25 EDT 2015


 

No, the U's aren't OK to ignore. That means you're under-running on the
TX side, which means missing samples. If you're getting a lot of them,
it means you aren't likely getting *any* good frames over the air. 

On 2015-07-28 11:47, Jason Matusiak wrote: 

>> How are you looping them back? With a lot of attenuation in the cable, I hope?
> 
> Sorry, that would have been useful for me to mention.... I am going over
> the air via an antenna.
> 
>> Also, it's useful when debugging this sort of thing to make your initial RX just an FFT display--does the spectrum look correct?
> 
> It looks pretty flat across the spectrum in this WiFi example. I also
> see a ton of U's and the occasional D's in the console. But in reading,
> it looks like the U's are OK to ignore.
> 
> I know when I did the OFDM loopback it looked like the attached.
 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.ettus.com/pipermail/usrp-users_lists.ettus.com/attachments/20150728/6a0512fd/attachment-0002.html>


More information about the USRP-users mailing list