Re: finding sample rate

On Aug 30, 1:05 am, Wills <wills.kingspan...@xxxxxxxxx> wrote:
On Aug 29, 4:03 pm, Colin Paul Gloster <Colin_Paul_Glos...@xxxxxxx>
wrote:



On 2007-08-29, Wills <wills.kingspan...@xxxxxxxxx> wrote:

|-------------------------------------------------------------------|
|"[..]If I have to take FFT should I sample the signal only in |
|powers of 2[..]?" |
|-------------------------------------------------------------------|

No, unless you are using something (e.g. a library) which needs you to.

|-------------------------------------------------------------------|
|"(2 power 20 samples or 2 power 21 samples, ofcourse |
|atleast >6000 samples)?" |
|-------------------------------------------------------------------|

2 to the power of 20 is >6000. 2 to the power of 13 is 8192 which is
the smallest number >6000 which can be obtained by raising 2 to the
power of a natural number.

Good luck,
Colin Paul Gloster

Thanks.
Should the number of samples be 2 power x?

Thanks in advance.

For FFT you should have 2^N number of samples, but you don't have to
have 2^M value of sampling frequency. Choose it basing on the
rejection factor of your anti-aliasing filter.
Good luck,
Alex.

.

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