Re: [Discuss-gnuradio] FFT size constraints?

[John Ackermann N8UR]

Thanks!  The mailing list seems to have been clogged up overnight, so 
after posting I did some experiments and found that an FFT of 100 bins 
to match 100 samples/second worked just fine and gives me exactly what I 
want -- nicely spaced results at 1 second intervals.

On 12/01/2017 11:19 AM, Sylvain Munaut wrote:
> > By convention, FFT sizes seem to be powers of 2.  And Gnu Radio Companion
> > throws an error if you try to set a size of 16384 -- but will accept 16383.
>
> Probably related to the size of the buffers or something like that.
>
>
> > Is using a non-power-of-2 FFT simply less efficient, or are there other
> > concerns?
>
> Power of 2 FFTs are faster (potentially _much_ faster), but you can do
> FFT of any sizes.
>
>
> Cheers,
>
>     Sylvain