digital synthesis

[Bjorn Wesen]

>How is your "easy FPGA" going to handle aliasing issues due to the
>waveform and aliasing issues due to FM modulation?


If you trivially generate waveforms with discontinuities digitally, like
sawtooth or triangle waves, you end up with aliasing, that is correct. You
need to make sure the signal is appropriately band limited. You can
manufacture alias-free basic "analog" waveforms like triangle, square and
sawtooth by integration of bandlimited impulse trains (the result remain
bandlimited).

Another option is of course to oversample so much that the aliasing is
negligable, but that seems a bit inefficient.

>   There already exist plenty of digital oscillator chips
>
>Which are these?

Any general DSP for example, and related asic implementations with dsp
cores.


/Bjorn