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What happens when sampling frequency is increased?
According to the Shannon Sampling Theorem, use a sampling frequency at least twice the maximum frequency component in the sampled signal to avoid aliasing. The following figure shows the effects of various sampling frequencies. In case B, increasing the sampling rate increases the frequency of the waveform.
How does aliasing effect can be reduced during the sampling process?
Aliasing can only be prevented by attenu- ating high frequency content before the sampling process as shown in Figure 2. To prevent aliasing completely, we must apply a perfect filter that passes all en- ergy from DC to the highest frequency of interest and rejects all energy at the Nyquist frequency and above.
When does sampling and aliasing occur in a signal?
When the sampling rate is not large enough (not larger than 2B Hz), then interference among adjacent bands will occur, and this results in the phenomenon of aliasing. In this case, the original signal cannot be recovered from the sampled signal.
What is the effect of aliasing on sound?
Obviously, aliasing has the effect of producing sounds of lower frequency from sounds that are higher in frequency than the Nyquist frequency. Once aliasing has occurred, it is absolutely impossible to distinguish a component generated by aliasing from one that was actually present in the input signal.
What happens when the sampling rate is too low?
A problem called aliasing occurs when a signal to be sampled contains energy at frequencies above the sampling Nyquist frequency. The next figure illustrates how aliasing would occur when the sampling rate is much too low for the frequency of an input signal. The solid curve represents the analog signal at a comparatively high frequency.
What is the theorem of sampling and aliasing?
Sampling and Aliasing Overview The sampling theorem states that a band-limited continuous-time signal, with highest frequency (or bandwidth) equal to B Hz, can be recovered from its samples provided that the sampling frequency, denoted