47
Select a suitable interpolation function:
At a small time base gear (50ns/div or smaller), there are few original sampling points
in one period and the displayed waveform has bad quality, so an interpolation function
is adopted to increase “sampling point” and rebuild the waveform, so that the
measurement precision is improved. Sine interpolation is suitable for sine, while linear
interpolation is suitable for triangular wave, square wave and similar. As shown in
figure 2-43 below, after sine interpolation, the displayed waveform is good, while figure
2-44 shows the waveform after linear interpolation of a sine signal, absolutely, the
waveform is bad, and the interpolation function is not selected rightly.
Figure 2-43 Sine interpolation
Figure 2-44 Linear interpolation
