I'm new to frequency domain analysis. Let's say I have a frequency domain representation from a time domain signal. What I want to do is taking frequencies with a low amplitude out of this frequency domain representation and then convert this frequency domain representation back to the time domain such that the result is almost the original time domain representation.
In Matlab what I want to do is something like this:
timeDomain(1:50) -> apply fft(timeDomain) -> inspect frequency domain and filter out low amplitude frequencies yielding a frequency domain vector x with length(x) probably (way) smaller than 50. (so x should contain only the frequencies with the highest amplitudes of the signal) -> apply ifft on this filtered complex vector -> Get an approximation of the original time domain signal (timeDomain(1:50) that has also length 50.
So my aim is to represent the time domain signal timeDomain(1:50) with less dimensions in the frequency domain without too much information about the signal getting lost, thus being able to reconstruct the time domain signal, so basically compression.
Thanks for your time.