Hi,
It's better to do the scaling inside the FFT when the intermediate
results have grown. Or even better do a data dependent scaling inside
the FFT when needed.
Best regards,
Jens J. Nielsen
http:/home.get2net.dk/jjn
On 25 Jul 2005 13:48:53 -0700, "DX" <diux007@gmail.com> wrote:
>Yes, it depends about the presicion, but it depends about the dsp's
>features to.
>The problem is that I have to use fixed point and the registers has 16
>bits to represent a fixed point, and if I don't scale the data they
>overflow the registers.
>
>Thank you.
>
>Diego
Reply by DX●July 25, 20052005-07-25
Yes, it depends about the presicion, but it depends about the dsp's
features to.
The problem is that I have to use fixed point and the registers has 16
bits to represent a fixed point, and if I don't scale the data they
overflow the registers.
Thank you.
Diego
Reply by Mr.Bilou●July 25, 20052005-07-25
| I'm writting a code to do a FFT using fixed point(16 bits). Well
this
| is the question What is the better, make the sacaling after or
before
| start a pass. I think that is better before start a pass. This is
| correct?
|
If results are divided by two to avoid overflow at each stage (like
the code I use)
You better scale your input buffer before processing the FFT.
Of course it depends of the precision you need !
Reply by Jerry Avins●July 24, 20052005-07-24
DX wrote:
> Hi.
>
> I'm writting a code to do a FFT using fixed point(16 bits). Well this
> is the question What is the better, make the sacaling after or before
> start a pass. I think that is better before start a pass. This is
> correct?
Processor?
--
Engineering is the art of making what you want from things you can get.
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Reply by DX●July 24, 20052005-07-24
Hi.
I'm writting a code to do a FFT using fixed point(16 bits). Well this
is the question What is the better, make the sacaling after or before
start a pass. I think that is better before start a pass. This is
correct?
Diego