On Mon, Dec 17, 2018 at 5:36 AM xavier yvars <xavier.yv...@gmail.com> wrote:

> x(t) = a*sin(w1t +  deltaphi*sin(w2t))
>
> With the "source block" it is not possible, you can just set a fixed
> frequency.
>

This is phase modulation of a carrier. You can implement it by multiplying
(multiply block) the carrier (signal source) with the output of a phase
modulator fed by the modulation signal which in this case is a sinusoid.

Example flow graph in GRC (numbers not particularly sensible, just
demonstrating it works):

[image: image.png]

Notes:

   - Your "deltaphi" parameter can be put into either the Amplitude of the
   signal source or the Sensitivity of the phase modulator; it's equivalent.
   - For maximum computational efficiency, replace the carrier source and
   Multiply block with a Rotator block. However, it requires the frequency to
   be expressed in radians per sample and so is not as convenient for casual
   use.
   - The output is complex (analytic). If you want real output, just use a
   complex to float block *after the multiplication.*
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