Howtosignalprocessing
- What effect will happen if sampling frequency is less than Nyquist rate?
- What is Nyquist frequency in image processing?
- What is Nyquist frequency and aliasing?
- What is the Nyquist effect?
What effect will happen if sampling frequency is less than Nyquist rate?
When the sampling frequency drops below the Nyquist rate, the frequencies will crossover and cause aliasing.
What is Nyquist frequency in image processing?
The frequency fNyq = dscan / 2 is called the Nyquist frequency. By definition fNyq is always 0.5 cycles/pixel. The Nyquist frequency can be visualized as the frequency that has two samples per cycle. Lower frequencies (more than two samples per cycle) can be reproduced exactly, but higher frequencies cannot.
What is Nyquist frequency and aliasing?
When the highest frequency (bandwidth) of a signal is less than the Nyquist frequency of the sampler, the resulting discrete-time sequence is said to be free of the distortion known as aliasing, and the corresponding sample rate is said to be above the Nyquist rate for that particular signal.
What is the Nyquist effect?
Nyquist's theorem states that a periodic signal must be sampled at more than twice the highest frequency component of the signal. In practice, because of the finite time available, a sample rate somewhat higher than this is necessary. A sample rate of 4 per cycle at oscilloscope bandwidth would be typical.
