I am trying to build a very simple FM Transmitter using a flowgraph as a reference. The principle is the following :
Signal source of 48 kHz Sample Rate > Rational Resampler up to 360 kHz Sample Rate > Add Constant 1 > VCO at 360 kHz with a carrier frequency at 120 kHz.
What I am trying to do right now is to replace the signal source with a vector of bits coming from another application to then modulate it with FM.
I've seen many examples of this kind of transmitter with audio input, but I don't understand how to pass it a vector of bits and to get the expected result.
Is there something I should consider before going to the VCO ? Is the principle only working with periodic signals as input ?
Thanks for your help!