Re: [Discuss-gnuradio] [USRP-users] B210 - file transmit using ofdm

[Marcus Müller]

Hi Julian,

in the future, please try to keep your questions on the mailing lists,
so that it's not like only one person can contribute experience.

In your case, maybe the discuss-gnuradio mailing list would be
interesting, sign up is under [1]. You'll find an archive there that
also answers your questions.

Now, in the interest of helping you as quickly as possible:

1. No, a USRP can only be owned by a single process, so yes, you'll have
to have it in one flow graph. You might use things like the GNU Radio
zeromq blocks to communicate data between flowgraphs – even running on
different machines!

2. Physics! Just because you don't screw on an antenna doesn't mean you
don't transmit signal out of your SMA connector (just much worse), and
also, there's inevitably a bit crosstalk between TX and RX on the same PCB.

Best regards,

Marcus

[1]https://lists.gnu.org/mailman/listinfo/discuss-gnuradio


On 21.03.2017 18:29, Tschuls Lebarski wrote:
> Hi Marcus,
>
> thank's a lot for your help.
>
> 1. Can I round 2 differnent flowgraph? One for receiving the other for
> transmitting? Or do I have to put UHD-Sink and Source together in one
> graph?
>
> 2.I tried playing with this examples and I modified tx_ofdm example to
> transmit a file.
> Instead of Random-Source I implemented File-Source and I added a
> File-Sink at the end of the receiving part.
> I replaced Chanel-Modulation with UHD-Sink and UHD-Source so there is
> no connection in flow graph between
> Transmitter and receiver part.
> The file was transmitted somewhere but I didn't use the antennas.....
> How can that be?
>
> Thanks in advance
>