Sampling can be done for functions capricious in space, time, or any added dimension, and agnate after-effects are acquired in two or added dimensions.
For functions that alter with time, let s(t) be a connected action to be sampled, and let sampling be performed by barometer the amount of the connected action every T seconds, which is alleged the sampling interval. Thus, the sampled action is accustomed by the sequence:
s(nT), for accumulation ethics of n.
The sampling abundance or sampling amount fs is authentic as the amount of samples acquired in one additional (samples per second), appropriately fs = 1/T.
Although a lot of of the arresting is alone by the sampling process, it is still about accessible to accurately reconstruct a arresting from the samples if the arresting is band-limited. A acceptable action for absolute about-face is that the non-zero allocation of the signal's Fourier transform be independent aural the breach –fs/2, fs/2.
The abundance fs/2 is alleged the Nyquist abundance of the sampling system. Without an anti-aliasing filter, frequencies college than the Nyquist abundance will access the samples in a way that is misinterpreted by the Whittaker–Shannon departure formula, the archetypal about-face formula. For details, see Aliasing.
For functions that alter with time, let s(t) be a connected action to be sampled, and let sampling be performed by barometer the amount of the connected action every T seconds, which is alleged the sampling interval. Thus, the sampled action is accustomed by the sequence:
s(nT), for accumulation ethics of n.
The sampling abundance or sampling amount fs is authentic as the amount of samples acquired in one additional (samples per second), appropriately fs = 1/T.
Although a lot of of the arresting is alone by the sampling process, it is still about accessible to accurately reconstruct a arresting from the samples if the arresting is band-limited. A acceptable action for absolute about-face is that the non-zero allocation of the signal's Fourier transform be independent aural the breach –fs/2, fs/2.
The abundance fs/2 is alleged the Nyquist abundance of the sampling system. Without an anti-aliasing filter, frequencies college than the Nyquist abundance will access the samples in a way that is misinterpreted by the Whittaker–Shannon departure formula, the archetypal about-face formula. For details, see Aliasing.
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