about sinc interpolation

HI all
  My problem is : i have a signal x(n)(0<=n<=N), and i get
y(k)=fft(x(n)),and 0<=k<=N; now , k=c*k',and c is a constant but c/=0; i
want to get y(k') from y(k),and 0<=k'<=N too.someone said i can use sinc
interpolation,what should i do? How to accomplish that? 

On Fri, 20 Jul 2007 09:32:21 -0500, p13dou wrote:

> HI all
>   My problem is : i have a signal x(n)(0<=n<=N), and i get
> 
> y(k)=fft(x(n)),and 0<=k<=N; now , k=c*k',and c is a constant but c/=0; i
> 
> want to get y(k') from y(k),and 0<=k'<=N too.someone said i can use sinc
> 
> interpolation,what should i do? How to accomplish that?

Have you done web searches on the keywords "FFT" and "interpolation"?

-- 
Tim Wescott
Control systems and communications consulting
http://www.wescottdesign.com

Need to learn how to apply control theory in your embedded system?
"Applied Control Theory for Embedded Systems" by Tim Wescott
Elsevier/Newnes, http://www.wescottdesign.com/actfes/actfes.html

>On Fri, 20 Jul 2007 09:32:21 -0500, p13dou wrote:
>
>> HI all
>>   My problem is : i have a signal x(n)(0<=n<=N), and i get
>> 
>> y(k)=fft(x(n)),and 0<=k<=N; now , k=c*k',and c is a constant but c/=0;
i
>> 
>> want to get y(k') from y(k),and 0<=k'<=N too.someone said i can use
sinc
>> 
>> interpolation,what should i do? How to accomplish that?
>
>Have you done web searches on the keywords "FFT" and "interpolation"?
>
>-- 
>Tim Wescott
>Control systems and communications consulting
>http://www.wescottdesign.com
>
>Need to learn how to apply control theory in your embedded system?
>"Applied Control Theory for Embedded Systems" by Tim Wescott
>Elsevier/Newnes, http://www.wescottdesign.com/actfes/actfes.html
>
Maybe I haven't state clearly. My orignal samples are huge,included in
x(i,k) ,which is a two dimension vector,and comes from some image. and one
dimension of x for every i(ie.x(i,:)) has been proformed fft process.i want
to rearray those samples with anothe dimension of x(:,k), so ,k=c*k' has to
been performed.Because the indexes of the samples have changed,and c is
changed from 0(bigger) to some value bigger than 1;but c is constant for
every i.
I have no idea of how to decide the 8 points sinc interpolation and the
related taylor window.I am appreciated for your further help and
suggestions.Thanx a lot.