Signal Phase using FFT

I have two cerebral signals registered for 10 minutes with a sample rate of 1000Hz. I have to extract the phase of the signals and the average phase displacement using FFT. The signals are represented by a 2x10000 matrix in MATLAB. How can I do that? Thank you in advance

Answer 1

[Shounak Shastri]

"I have to extract the phase of the signals and the average phase displacement using FFT"

Use the "fft" and the "fftshift" functions. The phase can be calculated by using the function 'angle' which will give you the phase and then unwrapping it by using the unwrap function. You can search the documentation for the explaination.

Here is an example in the matlab documentation https://in.mathworks.com/help/matlab/examples/fft-for-spectral-analysis.html

[Fed]

Thank you!

[Shounak Shastri]

You are welcome.

[Fed]

Now that I have calculated the phase using the functions “angle” and “unwrap”, I have to represent the phase of my signals in a polar plot as shown in the figure above. My signals are both 1x10000. I don’t know what to put as arguments of the “polarplot” or “polarscatter” command. How can I do that? Thank you in advance!