Aliasing occurs when sampling frequency is less than twice the highest frequency component (f_s < 2f_max)
Image: Margus Opp, CC BY-SA 4.0, via Wikimedia Commons
aliasing is: high frequencies masquerading as low frequencies due to undersampling
Aliasing occurs when sampling frequency is less than twice the highest frequency component (f_s < 2f_max)
Aliasing happens when the sampling frequency (f_s) is less than twice the highest frequency component (f_max) of the original signal. This causes high frequencies to masquerade as low frequencies in the reconstructed signal.
Example
If a signal contains a frequency component of 500 Hz and it is sampled at 800 Hz, aliasing will occur because the sampling frequency is less than twice the highest frequency component (800 Hz < 2 × 500 Hz).
Remember this
Understanding aliasing is crucial for designing systems that avoid distortion and artifacts in digital signal processing.
Text adapted from Wikipedia, licensed under CC BY-SA 4.0.
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