Re: controlling gain of USRP Sink

On 15/12/2023 15:58, Manuel Caldas wrote:
>
> Hi all,
>
> I am using an Ettus b200 mini for transmitting a tone at 4GHz (which
> in turn feeds a radiometer), through a signal source block and a USRP
> Sink. Also in my flowgraph I have a Qt GUI Range for manually setting
> the USRPs Gain. I manually change the gain and see perfectly in a
> fosphor sink how the power spectrum changes accordingly.
>
> What I now want to do is to make the Gain follow a gaussian evolution
> over time (a single pulse is fine), which of course is not practical
> nor accurate to accomplish by manually changing the gain slider.
>
> So, is there any way to achieve this? I'm using grc 3.10.8.0 (Python
> 3.11.6) on a win 10 PC.
>
> (btw, what I am actually trying to do is to simulate the transit of a
> radioastronomical point signal in front of an antenna, and see how my
> radiometer responds to that).
>
> Best regards and thanks in advance!
>
> /Manuel
>
>
I would instead of changing the RF gain, change the baseband magnitude
over time -- probably using a custom embedded
  Python block -- if the sample rates aren't too high.