How can I normalize a window function for accurate Fourier transforms?

[TheDestroyer]

Hello guys :)

I'm applying a window function to a signal before using a Fourier transform on it, but the problem is that the Fourier transform's amplitude (RMS or Volt/Sqrt(Hz)) is changing. Some windows are normalised to retain the amplitude. I'm making sure this is happening by Fourier transforming white noise before and after applying the window.

Could you guys tell me how to start with normalising a window? I tried simply dividing by the integral but it wasn't a good idea. I don't know where to start.

Thank you for any efforts :)

 

[TheDestroyer]

I think normalising the Window to RMS did it. Thank you :)