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

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Channel Menu R&S
®
ZVA/ZVB/ZVT
1145.1084.12 4.156 E-6
excluded from the measurement, it can still be used as a receive port. On the other hand, an
excluded port (Meas = Off) can still be used as an RF signal source.
The source must be switched on to perform a system error correction or a source power
calibration for the source port.
•
Gen qualifies whether the RF signal source at the port is switched on for all partial
measurements (box checked, permanent signal source) or only for the partial measurements
that require the port as a drive port.
Dependencies: Gen has no effect unless the RF source at
the port is switched on (RF Off is not checked). A port which is excluded from the measurement
(Meas = Off) can still be used as a permanent RF signal source.
External generators
An external generator always represents a permanent signal source that is switched on for all partial
measurements. Gen qualifies whether or not the generator is actually available as a signal source in the
test setup.
The analyzer provides two alternative ways of selecting a generator as a signal source:
•
Gen: On in the Port Configuration dialog, especially if the generator is not assigned to a
particular measured quantity or drive port.
•
Selection as a source for a particular measured quantity or for a power calibration, see e.g.
More Wave Quantities.
The two selection mechanisms are independent from each other.
Permanent vs. intermittent RF signal source
Switching on the signal source permanently eliminates the power settling times of the DUT but may
introduce measurement inaccuracies. Therefore, the parameter must be switched off to perform a
system error correction.
For triggered measurements, it is possible to switch off the signal source between the end of a
measurement cycle and the next trigger event; see Trigger Starts .
•
Frequency opens an input box to define a port-specific stimulus frequency range (for frequency
sweeps) or CW frequency (for power, time and CW Mode sweeps). In the default configuration
the stimulus parameters (sweep range, CW Frequency) are used. The result is displayed in the
Frequency Result column. A red Frequency field indicates that the hardware limits are
exceeded, e.g. if the default sweep range of the analyzer is beyond the frequency range of the
external generator.
Test ports 1 and 2 and test ports 3 and 4 are supplied by a common synthesizer (see ZVA block
diagrams in the data sheet). As a consequence, the source frequencies at the two pairs of ports
must be the same.
•
Frequency Result displays the current frequency range (for frequency sweeps) or CW
frequency (for power, time and CW Mode sweeps); see stimulus parameters.
•
Power opens an input box to define a port-specific source power range (for power sweeps) or
fixed power (for frequency and CW sweeps). The result (not taking into account a possible
Slope) is indicated in the Power Result column. In the default configuration the stimulus
parameters (sweep range, internal source Power) are used.
•
Power Result displays the current power range (for power sweeps) or fixed internal source
power (for frequency, time and CW Mode sweeps); see stimulus parameters.
•
PCor Off enables or disables a source power calibration for an individual port. This function is
available only for ports where a source power calibration is available. It is identical with Source
Power Correction Off in the Source Power Cal menu.