DPO6000
，
MPO6000 Series Digital Phosphor Oscilloscope Instruction V1.1
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3.2.Sample rate and memory depth
3.2.1.Sample rate
The highest sample rate of DPO6000/MPO6000 is 1GSa/s.In the actual use of
oscilloscopes, the sample rate is determined by the current horizontal timebase gear and
memory depth. The sample rate can be changed by adjusting the horizontal timebase
through the horizontal gear knob, or by changing the memory depth, and the sample rate
value can be changed in real time and displayed in the status bar in the upper left corner
of the screen.
3.2.2.Memory depth
Memory depth refers to the number of waveform points that the oscilloscope can store in a
single trigger sample and it reflects the storage ability of the sample memory.
DPO6000/MPO6000 series oscilloscope provides up to 24 Mpts memory depth.The
relation of memory depth, sample rate and sample time of the oscilloscope fulfills the
equation below:
Sampling time = storage depth/sampling rate (Sa/s)
For example,sample rate is 1GSa/s,memory depth is 32K,the actual sample time is:
Sampling time=
000
,
000
,
000
,
1
32000
s =32 x 10
-6
s=32us
3.3.Waveform interpolation,methods
Under real-time sampling, the oscilloscope obtains the discrete sample values of the
displayed waveform. In general, the waveform shown by dots is difficult to observe. In
order to increase the visibility of signal, digital oscilloscope generally adopts interpolation
display mode. Interpolation is a method of "connecting all points" and using some points
to calculate the whole waveform. For real-time sample using interpolation method, even if
the oscilloscope only collects a few sampling points in one way, it can also use
interpolation method to fill the gap between points and reconstruct the accurate waveform.
Interpolation method is divided into sine interpolation, linear interpolation, step
interpolation.
3.3.1.Linear interpolation
:
Directly connect the line at the adjacent sample point.This approach is limited to the
reconstruction of edge-only signals, such as square waves. Sine interpolation method
uses curves to connect sampling points, which is more universal.
