Rohde & Schwarz 1145.1010.04/05/06, Руководство по эксплуатации

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System Menu R&S
®
ZVA/ZVB/ZVT
1145.1084.12 4.264 E-6
5. Select the measurement bandwidth and source power
Choose a typical measurement bandwidth and one of two typical source power values. A
smaller measurement bandwidth increases the dynamic range but slows down the
measurement. A smaller source power protects the input port of the analyzer from being
overdriven if an active DUT with high gain is measured.
The predefined bandwidths and source powers have been selected according to the
following criteria:
•
The large measurement bandwidth (Fast Sweep) ensures that the noise of a S
21
trace
at minimum (–40 dBm) source power and 0 dB attenuation is smaller than 0.1 dB.
•
The default source power for a passive DUT ensures that the analyzer receiver is in its
linear range (no compression) if a passive DUT with 0 dB attenuation is measured. The
default source power for an active DUT ensures no compression if an active DUT with
20 dB gain is measured. If the actual gain of the DUT is more than 30 dB, then the
default source power of –20 dB is still too high and needs to be changed after finishing
the wizard.
6. Perform a calibration (optional)
Call up the calibration wizard and perform a calibration. The calibration type is a full n-port
calibration, where n is the number of analyzer ports selected in the first stage of the calibration
wizard. This calibration can be performed as well using automatic calibration (if accessory R&S
ZV-Z51 or R&S ZV-Z58, Calibration Unit, is available).
You can skip the automatic calibration stage (select Finish now without calibraton) if
•
A valid calibration is already assigned to the active channel
•
You want to apply a valid calibration stored in the cal pool
•
You want to perform the calibration manually, e.g. because you wish to select another
calibration type.
•
You don't want to use a calibration, e.g. because the factory calibration is accurate
enough for your measurement.
In order to obtain a predictable result the measurement wizard has to reset all settings except the
current calibration data. Store your setup if you don't want to lose the current configuration.