TiePie Handyscope HS5 series, User Manual

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Figure 3.2: ”connecting” the samples
3.2 Sample frequency
The rate at which the samples are taken is called the sampling
frequency , the number of samples per second. A higher sampling
frequency corresponds to a shorter interval between the samples.
As is visible in figure
3.3 , with a higher sampling frequency, the
original signal can be reconstructed much better from the measured
samples.
Figure 3.3: The effect of the sampling frequency
The sampling frequency must be higher than 2 times the high-
est frequency in the input signal. This is called the Nyquist fre-
quency . Theoretically it is possible to reconstruct the input signal
with more than 2 samples per period. In practice, 10 to 20 sam-
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Chapter 3