## Matlab - How To Use Fft And Fftshift. Fourier Transform

Transcript:

Hi, everyone today in rated continue. And what you need to do to get the proper whistles, okay. First of all function for fully transform is a 50/50 transform. You can put the point you want for the function and you put your signal. This is [Music] not decorate. Say you get the values, but you get it in a wrong positions so for that, we have another. Fft function is called FFT shift. So here is an example in my word. The result of the FFT also is an example and showing the different that you use with the FFT shift with the FFT. You get the fully transform, but when you plot it, you get the values wrong. Why because the frequencies are not in the center so here they show you value sample with some values when you do? FF shift, let’s see you had your body. Do better here from 1 to 6 I’m going to apply the fft shift function. You get ordered from the center. So will you had 6 values of 3 to the left 3 to the right and to the right you start with the first one 1 2 3 on to the latest are 4 5 6 your second one with more 3 5 saving also the same 1 2 3 4 5 6 so at the moment. What, like only a 50 you get this, but this is. There is not the center here. The Center of frequency is not correct, so for that, you have to use the FFT shift after after the FFT. So you first apply the FST here you can see the variable name is X X Here. Then you apply the fft she to that specific signal you get. Y also you’re better to plot. You need to put it from minus N to positive and the frequency sample. So in that case, you can have from 0 to the left. The negative value to 0 to the right positive value a weekend, and we know for for the Fourier transform or thank signal. You can see here. We have one pole once here. One value for negative one value for positive. So does the correct answer which we were doing fully transform in my lap and that’s. Why you need to do. So that’s why we use. Fft chief, after FFT. So you need to create you better. Be a competitor has to be correct. If you don’t do it, you will get all the value here. The magnitude will be wrong. So you need to divide it, but all your samples, other example, do you like? I will put this on the description. This link, so you can check the sample by yourself with more details, ok? I hope this helped for you. Please give rely and.