Send USRP-users mailing list submissions to
[email protected]
To subscribe or unsubscribe via the World Wide Web, visit
http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
or, via email, send a message with subject or body 'help' to
[email protected]
You can reach the person managing the list at
[email protected]
When replying, please edit your Subject line so it is more specific
than "Re: Contents of USRP-users digest..."
Today's Topics:
1. Severe DC offset ([email protected])
----------------------------------------------------------------------
Message: 1
Date: Sun, 13 Mar 2011 17:21:36 -0400
From: [email protected]
To: [email protected]
Cc: [email protected]
Subject: [USRP-users] Severe DC offset
Message-ID: <[email protected]>
Content-Type: text/plain; charset="iso-8859-1"; Format="flowed";
DelSp="Yes"
I'm trying to decode 80211.g packets using the USRP2 and the XUPV5.
When I use the old USRP2 code (not the UHD build, but code obtained
off of gnuradio head), I don't receive packets. This appears to be
caused by enormous power in the DC band. When I collect similar
traces using UHD code, I see no such DC offset and I can decode
packets without issue.
I'm wondering what could have happened to cause this discrepancy. The
DSP code appears to be the same between the two FPGA builds. My
current belief is that something changed in the software configuration
during the move to UHD.
Is there some kind of software post-processing going on in the new
build? Do I need to manually remove the DC offset using the the
dcoffset registers in the rx dsp block?
I have attached power spectra showing the difference between UHD and
the old code load.
-Kermin
-------------- next part --------------
A non-text attachment was scrubbed...
Name: old.png
Type: image/png
Size: 160703 bytes
Desc: not available
URL:
<http://lists.ettus.com/pipermail/usrp-users_lists.ettus.com/attachments/20110313/a0e9d856/attachment.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: good.png
Type: image/png
Size: 256675 bytes
Desc: not available
URL:
<http://lists.ettus.com/pipermail/usrp-users_lists.ettus.com/attachments/20110313/a0e9d856/attachment-0001.png>
------------------------------
_______________________________________________
USRP-users mailing list
[email protected]
http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
End of USRP-users Digest, Vol 7, Issue 24
*****************************************
