How To Change Tx Frequency During Transmission

GNU Radio
1

Hello everyone,

Does anyone know how to change Tx frequency during transmission. I mean
the
transmitter operates at f0 GHz in some interval of time and then change
to
operate at f1 GHz.

Sincerely,
Van-Ly

Van-Ly Nguyen,
Research Assistant,
Signals and Systems Laboratory - SSL
Faculty of Electronics and Telecommunications - FET
University of Engineering and Technology - UET
Vietnam National University, Hanoi - VNU

Tel: (+84) 97 881 9406

2

Hello Van-Ly,

what hardware are you using?
If you’re using any USRP, then the gr-uhd [1] blocks [2] will allow you
to tune using stream tags, asynchronous messages and method calls.
From your problem description, it sounds like using stream tags is your
best choice. If you want to know more about how to use these, I
recommend going through the new guided tutorials [3], especially part 5
(which kind of relies on you having read the first four parts, but since
I think you’re already somewhat friends with GNU Radio, this might not
be too much work).

Greetings,
Marcus

[1] GNU Radio Manual and C++ API Reference: UHD Interface
[2] sink:
GNU Radio Manual and C++ API Reference: gr::uhd::usrp_sink Class Reference
[3] http://gnuradio.org/redmine/projects/gnuradio/wiki/Guided_Tutorials

3

Hi Marcus,

I use bladeRF hardware, not USRP. So I have “osmocom” sink and source
blocks in my flow graph. Do you have any idea about this.
Thank you very much,

Best Regards,
Van-Ly

Van-Ly Nguyen,
Research Assistant,
Signals and Systems Laboratory - SSL
Faculty of Electronics and Telecommunications - FET
University of Engineering and Technology - UET
Vietnam National University, Hanoi - VNU

Tel: (+84) 97 881 9406

On Wed, Dec 3, 2014 at 10:28 PM, Marcus Müller
[email protected]

4

Hi Ly, you might consider as an alternative solution shifting the
frequency by multiplying with a sine wave if your application can sample
at high rate.