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R&S ZVL
GUI Reference
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Operating Manual 1303.6580.32-06
148
unchanged but may increase the sweep time, due to the additional sweep points introduced.
The three grids can be calculated repeatedly in any order; the analyzer always starts from the original set
of sweep points.
•
Visualization of the harmonic grid algorithms
The three types of harmonic grids have the following characteristics:
•
Keep
Stop Frequency and Number of Points
means that the stop frequency and the number of
sweep points is maintained. The sweep points are re-distributed across the range between the
minimum frequency of the analyzer and the stop frequency; the step width may be increased.
•
Keep
Frequency Gap and Number of Points
means that the number of sweep points and their
relative spacing is maintained. The entire set of sweep points is shifted towards lower frequencies
so that the stop frequency is decreased.
•
Keep
Stop Frequency and Approximate Frequency Gap
means that the stop frequency is
maintained and the number of sweep points is increased until the range between f
min
and the stop
frequency is filled. The frequency gap is approximately maintained.
The figures above are schematic and do not comply with the conditions placed on the number of
sweep points and interpolated/extrapolated values.
The harmonic grids can not be calculated for any set of sweep points. If the minimum number of
sweep points is smaller than 5, then the interpolation/extrapolation algorithm for additional sweep
points will not work. The same is true if the number of sweep points or stop frequency exceeds the
upper limit. Besides, the ratio between the sweep range and the interpolation range between f = 0
and f = f
min
must be large enough to ensure accurate results.
If the sweep range for the harmonic grid exceeds the frequency range of the current system error
correction, a warning is displayed.
Finding the appropriate algorithm
The three types of harmonic grids have different advantages and drawbacks. The following table helps
you to find the appropriate grid.