Windowed FFT magnitude / leakage effect

Question

Tom Bedkowski 2019-7-5

编辑： Tom Bedkowski 2019-8-1

Hello,

i am doing an windowed fft to get the magnitude by a frequency.

But the result of the magnitude is not the magnitude of the sampled summation of sinusfunction, which i defined.

This effect is the leakage effect and i heard about a correction factor to get the right magnitude from the windowed fft.

Thank you for help!

Answer 1

Samatha Aleti 2019-7-17

Hi,

You may calculate & apply Amplitude correction factor to compensate the leakage effect. Here is an example

N= 100; 
w = hann(N); 
% correction factor
Cf=length(w)/sum(w); 

Tom Bedkowski 2019-8-1

编辑：Tom Bedkowski 2019-8-1

Thank you for help.

Yes that is the first correction which i done.

But there is a futher correction which depends on the specific window.