Fft aliasing

1. What is aliasing in FFT?
2. What is aliasing of frequency spectrum?
3. What is meant by aliasing effect?
4. What is aliasing effect formula?

What is aliasing in FFT?

Recognizing Aliasing in the FFT

It is common to have acquired signals with a fundamental frequency less than half the sample rate, but the harmonics of that signal may be greater than half the sample rate and they will alias. This shows up in the FFT as frequencies that fold back into the display.

What is aliasing of frequency spectrum?

Those high frequencies fold back onto the spectrum of the discrete time series and appear as lower frequencies. The phenomenon that is caused by undersampling the continuous signal is termed frequency aliasing.

What is meant by aliasing effect?

Answer : Aliasing occurs when an oscilloscope does not sample the signal fast enough to construct an accurate waveform record. The signal frequency is misidentified, and the waveforms displayed on an oscilloscope become indistinguishable. Aliasing is basically a form of undersampling.

What is aliasing effect formula?

Aliasing is the name we give to the phenomenon when two distinct continuous signals x 1 ( t ) and x 2 ( t ) produce the same sequence of sample values when sampled at a fixed rate . More specifically, we usually think of aliasing in terms of pure (sinusoidal) tones x ( t ) = A ⋅ cos ⁡ ( 2 π ⋅ f ⋅ t + ϕ ) .