Howtosignalprocessing
- What does an FFT spectrum show?
- What is the difference between FFT and power spectrum?
- Does FFT give power spectrum?
- Why is FFT symmetric?
What does an FFT spectrum show?
The resulting digital time record is then mathematically transformed into a frequency spectrum using an algorithm known as the Fast Fourier Transform, or FFT. The FFT is simply a clever set of operations which implements Fourier's theorem. The resulting spectrum shows the frequency components of the input signal.
What is the difference between FFT and power spectrum?
The PSD and FFT are tools for measuring and analyzing a signal's frequency content. The FFT transfers time data to the frequency domain, which allows engineers to view changes in frequency values. The PSD takes another step and calculates the power, or strength, of the frequency content.
Does FFT give power spectrum?
Power spectrum analysis is a technique commonly used by PID tuning software and applies a fast Fourier transform (FFT) to the variation of a particular signal to compute its frequency spectrum. The result is presented as a plot of signal power against frequency and is referred to as its power spectrum.
Why is FFT symmetric?
Because both the positive and negative frequency sinusoids are 90 degrees out of phase and have the same magnitude, they will both respond to real signals in the same way.
