help with ifft

[detech]

I try to use fft and ifft to make a filter, to remove some frequencies and then convert to time domain. I have problems to do it. To make it simple I attach a lv 2009 example, which has two component 10 hz and 15 hz input.

Can you help me in removing 15 hz after FFT and then convert with IFFT. Just to check if only 10 hZ signal left after IFFT.

If you can give me an example like this, my problem will be solved.

Thanks

Liming

[smercurio_fc]

moved from here

[smercurio_fc]

Did you try the Filter VI?

[detech]

I did use filter, but I do not know what filter does inside. I really want to do this basics, which I can compare with results from other software.

Please see if you can help..

[detech]

That does not help me. My question is a basic FFT and IFFT. It related to the component numbers, 2^n in time domain and 2^(n-1) + 1 in frequency domain. When remove one frequency fron FFT, need to remove two component.....

[Greg_J]

Hi detech,

Check out this KnowledgeBase: How Do I Use the FFT and Inverse FFT VIs in LabVIEW?  It explains the use of FFT and IFFT tools in LabVIEW as well as providing an example (per your original request) and some additional links for your reference.

I hope this helps!

- Greg J