>Peter123 wrote:
> > I am sampling voltage values. I need to convert it to the frequency
>domain
> > using FFT .
> > As I understand the frequency steps after FFT will be the integer
> > multiples of Fs/N (where Fs is the data sample rate in Hz, and N is
>the FFT
> > length).
> > How can I have sub-Hz frequency steps?
>
>Sample for a longer time.
>
> > Do I use use long sampling times and long FFT lengths, for instance,
> > Sampleing at 1 kHz and using 10000 FFT length will produce 0.1Hz
>frequency
> > steps, and the sample stream will be 10 seconds long?
> > Am I on the right track?
>
>Yes.
>
> > Thanks
> > Peter, pr20@cornell.edu pls, also e-mail copy of your reply.
>
>Jerry
>--
>Engineering is the art of making what you want from things you can get.
>�����������������������������������������������������������������������
>** Posted from http://www.teranews.com **
>
Reply by Jerry Avins●October 9, 20082008-10-09
Peter123 wrote:
> I am sampling voltage values. I need to convert it to the frequency
domain
> using FFT .
> As I understand the frequency steps after FFT will be the integer
> multiples of Fs/N (where Fs is the data sample rate in Hz, and N is
the FFT
> length).
> How can I have sub-Hz frequency steps?
Sample for a longer time.
> Do I use use long sampling times and long FFT lengths, for instance,
> Sampleing at 1 kHz and using 10000 FFT length will produce 0.1Hz
frequency
> steps, and the sample stream will be 10 seconds long?
> Am I on the right track?
Yes.
> Thanks
> Peter, pr20@cornell.edu pls, also e-mail copy of your reply.
Jerry
--
Engineering is the art of making what you want from things you can get.
�����������������������������������������������������������������������
** Posted from http://www.teranews.com **
Reply by Peter123●October 9, 20082008-10-09
I am sampling voltage values. I need to convert it to the frequency domain
using FFT .
As I understand the frequency steps after FFT will be the integer
multiples of Fs/N (where Fs is the data sample rate in Hz, and N is the FFT
length).
How can I have sub-Hz frequency steps?
Do I use use long sampling times and long FFT lengths, for instance,
Sampleing at 1 kHz and using 10000 FFT length will produce 0.1Hz frequency
steps, and the sample stream will be 10 seconds long?
Am I on the right track?
Thanks
Peter, pr20@cornell.edu pls, also e-mail copy of your reply.