Rohde & Schwarz R&S UPP, Руководство пользователя

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Instrument Functions
R&S
®
UPP
350 User Manual 1411.1055.32 ─ 10
Note: If the start condition "Time Tick" is combined with the frequency sweep of the
selective RMS measurement or a synchronous generator sweep, the number of sweep
points is taken from there and cannot be entered separately.
Remote command:
TRIGger:COUNt
on page 734
5.19 External Sweeps and Level-Controlled Measured
value Triggering
External sweeps are usually controlled by means of an external signal source. The
internal sweep generator should not be active in this case. A warning message is out-
put if the internal sweep generator is still active when an external sweep is activated.
Basically, the internal sweep generator can be used as a signal source also with exter-
nal sweeps . This is meaningful, for example, if the delay of the DUT is not known or
not constant and it is, therefore, not possible to couple the generator stepping perma-
nently to the measurement start. Sweep stepping is performed as usual, but measure-
ment does not start until a trigger event occurs.
The generator should be stepped in a time-controlled manner (dwell sweep; setting in
generator: "Next step" = "dwell value" or "dwell file"), in order to achieve independence
from generator sweep stepping and measurement.
For analyzer-synchronous stepping (setting in generator: "Next Step" = "Anlr Sync"), it
is important to ensure that each sweep step extends beyond the variation selected for
the start condition. If this condition is not met, the external sweep comes to a stop.
The following rules must be followed for setting the generator sweep in the case of an
external sweep:
●
"Spacing" must be set to "Log Steps" (optional for dwell sweep).
●
The sweep direction (specified by the sequence between "Start" and "Stop") must
agree with the recording direction chosen in the analyzer.
●
The sweep range must be within the recording range (optional for dwell sweep).
●
The step width, or increment (specified in the generator as a factor under "Step")
must be greater than "Variation" in the analyzer (optional for dwell sweep).
for upward sweeps (Start < Stop): Step > 1 + Variation / 100
for downward sweeps: (Start > Stop): Step < 1 – Variation / 100
External Sweeps and Level-Controlled Measured value Triggering