Hi,
Recently I have been testing the examples of Gnu Radio. And I came
across some problems. When I use a USRP with two daughterboards, I found
that the two daughterboards can not trismit or receive at the same time.
They can only work as one transmitter and one receiver. I want to know
whether we can use both daughterboards as transmitters or receivers?
What should I do do achieve it?
Any reply will be appreciated!
Recently I have been testing the examples of Gnu Radio. And I came across
some problems. When I use a USRP with two daughterboards, I found that the
two daughterboards can not trismit or receive at the same time. They can
only work as one transmitter and one receiver. I want to know whether we can
use both daughterboards as transmitters or receivers? What should I do
do achieve it?
Any reply will be appreciated!
Have a look at the ‘multi-antenna’ examples. They show how to
properly de-mux multiple basic-rx daughtercards. If you want to
de-mux other daughtercards the process is similar, but the custom FPGA
image used in those examples won’t work, and you’ll only be able to
de-mux two channels on a given USRP.
I thought there was an example for generic cards around but I can’t
seem to find it, maybe someone else knows where it is?
Jason
I thought there was an example for generic cards around but I can’t
seem to find it, maybe someone else knows where it is?
This is a quick example derived from some code I use when I want to
just capture random data for post processing.
http://www.jasonuher.com/toys/gnuradio/multi_rfx/multi_Nx2_rx.py
All it does is open both daughtercards and save the stream for a set
amount of time. Transmission just as simple; it is the opposite, but
I don’t really have anything sanitized to share with you right now.
I’ll put it on my ‘to do eventually’ list.
Remember that there is a fixed phase offset between both channels
because of the un-linked accumulators in the ADCs. My ‘to do
eventually’ list also has ‘write fpga image w/o this offset’, but for
now you will just have to account for it when you develop.
Jason
2010/4/27 jlsdxw [email protected]:
Hi,
 Recently I have been testing the examples of Gnu Radio. And I came across
some problems. When I use a USRP with two daughterboards, I found that the
two daughterboards can not trismit or receive at the same time. They can
only work as one transmitter and one receiver. I want to know whether we can
use both daughterboards as transmitters or receivers? What should I do
do achieve it?
 Any reply will be appreciated!
If you start GRC you’ll find a “USRP Dual Source” and a “USRP Dual
Sink” and that will enable you to use both receivers and transmitters
at the same time. I tried the attached example with WBX+RFX2400 cards
and it works fine. If I replace one of the cards with LFRX and LFTX it
will say:
“Cannot compute dual mux when mixing quadrature and non-quadrature
subdevices”
so maybe that was your problem?
Alex