GUI Reference
R&S
®
ZNB/ZNBT
497
User Manual 1173.9163.02 ─ 38
Set Harmonic Grid and Keep
The three buttons provide alternative algorithms for calculation of a harmonic grid,
based on the current sweep points.
●
Keep "Stop Frequency and Number of Points" calculates a harmonic grid based on
the current "Stop Frequency" (see
"Start Frequency / Stop Frequency / Center Fre-
on page 430) and the current number of sweep points
(see
on page 240). This may increase the frequency gap (i.e.
the
●
Keep "Frequency Gap and Number of Points" calculates a harmonic grid based on
the current "Stop Frequency" and the current frequency gap (i.e. the "Freq Step
Size").
●
Keep "Stop Frequency and Approximate Frequency Gap" calculates a harmonic
grid based on the current "Stop Frequency", increasing the "Number of Points" in
such a way that the frequency gap (i.e. the "Freq Step Size") remains approxi-
mately the same. This 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.
Chapter 4.7.2.4, "Harmonic Grid"
Remote command:
CALCulate<Chn>:TRANsform:TIME:LPASs
Automatic Harmonic Grid
If enabled (default) the frequency grid is automatically kept harmonic.
Remote command:
DC Value
The control elements define the measurement result at zero frequency and in the inter-
polation/extrapolation range between f = 0 and f = f
min
. They are enabled after a har-
monic grid has been established.
Defining the low frequency sweep points
After calculating a harmonic grid, the analyzer must determine the value of the mea-
sured quantity at zero frequency and possibly at additional points in the range between
f = 0 and f = f
min
.
The following figure shows a scenario where the harmonic grid was calculated with
fixed "Stop Frequency and Number of Points". The DC value and the values at the two
additional red points must be extrapolated or interpolated according to the measured
sweep points (blue dots) and the properties of the DUT.
Trace Config Softtool