Hi Marcus,
I have many USRPs N210 with different daughterboards. I tried with both
SBXv3 and WBXv3 daughterboards and the result is the same : the spikes
appear. The only difference is the spikes amplitude but it's not
suprising because I noticed that with the same transmission paramaretes
Hi Raphael,
don't think switching from GNU Radio to directly talking to UHD will
change much – the GNU Radio USRP Sink is pretty much a thin wrapper
around UHD.
You might have already said that, but I can't find in this email chain:
What's the daughterboards you're using in your TX USRP N210?
Hi Marcus,
I'm only sending bursts of "null packets". I send them every 400 ms and
I notice at the receiver side that the spikes happen exactly at the
beginning of EACH transmission of null packets (for this verification I
use GPS clock on the the transmitter and the reveiver).
It's like if
Dear Raphael,
> Don't you think that 40-60ms is a bit long fot the amplifier to shut
down
I didn't say it was the amplifier shutting down. I supposed it was the
DC offset cancellation!
Your recording is very interesting. I assume the "spike" you see
happens exactly when you turn on the
Hi Marcus,
Thanks for your help. Don't you think that 40-60ms is a bit long fot
the amplifier to shut down ? I tried to increase the gain at the
receiver and the sender sides but I still have the problem.
More important, I tried an other scenario by sending a burst of symbols
whose value is
Hi!
This might really be the fact that the amplifier takes some time to
shut down. This, paired with the possibility of TX/RX crosstalk might
be a contributing factor: That might actually change the DC offset on
the receiving side, and trigger the step response of the DC offset
cancellation
Hi Raphaël,
not quite sure I get your problem, but this is rather hard to debug
without knowing exactly what your transmitter does.
For example, if you transmit something that isn't zero-mean, then the
DC offset cancellation *in* the receiving end would start to cancel
out. As that cancellation
Hello,
For more details, please find attached the received signal in the time
domain. Clearly after the end of the packet, the signal takes a certain
time to come back to "the ambient noise". If I zoom, I notice there is
still some noise 40ms after the packet. It can disturb the reception of
Hello Dan,
Thanks for your answer. I'm using for transmitting the traditional USRP
sink block provided by Gnuradio Companion. Each packet coming to this
block is tagged with its length at the first sample. For the receiving
part, I'm using the USRP source block. Both are used with basic
