Aliasing

Also known as "Under-Sampling". Aliasing is an undesired effect of under-sampling.

It occurs when a signal is not being sampled fast enough.

Mathematically, this occurs when:

$ w_s\leq 2w_n $


also as


$ \dfrac{2\pi}{T_s}\leq 2w_n $


for


$ w_s = \dfrac{2\pi}{T_s} $


This is closely tied to the Nyqust theorem, where if you are sampling beneath the Nyqust value, the signal will collide with itself, making it no longer perfectly recoverable.

Alumni Liaison

Ph.D. 2007, working on developing cool imaging technologies for digital cameras, camera phones, and video surveillance cameras.

Buyue Zhang