Howtosignalprocessing
- What is an alias frequency?
- What is alias signal?
- What is aliasing how a band-limited signal can be sampled without aliasing?
- What is Nyquist frequency and aliasing?
What is an alias frequency?
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 alias signal?
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 how a band-limited signal can be sampled without aliasing?
Aliasing allows higher frequencies to disguise themselves as lower frequencies, as can be seen in Figure 3. Thus, the minimum sampling frequency necessary for sampling without aliasing is 2BW. This result is generally known as the Nyquist criterion. Figure 3 depicts a sampled signal suffering from aliasing.
What is Nyquist frequency and aliasing?
When a component of the signal is above the Nyquist, a sampling error occurs that is called aliasing. Aliasing “names” a frequency above Nyquist by an “alias” the same distance below Nyquist. Sinusoidal signal at 1.3 times Nyquist before sampling into pixels.
