Rohde & Schwarz NRP TWG Series, Руководство пользователя

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Remote Control Commands
R&S
®
NRPxxTWG
65 User Manual 1178.8371.02 ─ 04
calculates the power at the input of the attenuator or the directional coupler. A negative
offset can be used to correct the influence of an amplifier connected ahead.
Using S-parameters instead of a fixed offset allows more precise measurements,
because the interaction between the sensor and the component can be taken into
account. See also
Chapter 7.8.3.3, "S-Parameter Correction" , on page 65.
Remote commands:
[SENSe<Sensor>:]CORRection:OFFSet
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[SENSe<Sensor>:]CORRection:OFFSet:STATe
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[SENSe<Sensor>:]CORRection:OFFSet <offset>
Sets a fixed offset that is added to correct the measured value.
Parameters:
<offset> Range: -200.00 to 200.00
*RST: 0
Default unit: dB
[SENSe<Sensor>:]CORRection:OFFSet:STATe <state>
Enables or disables the offset correction.
Parameters:
<state> *RST: OFF
Example: CORR:OFFS:STAT ON
7.8.3.3 S-Parameter Correction
S-parameter correction compensates for the losses and reflections introduced by a
component – such as an attenuator, directional coupler, or matching pad – that is
attached to a power sensor. Using S-parameters instead of a fixed offset increases
measurement accuracy by accounting for the interaction between the sensor and the
component. It shifts the reference plane of the sensor from its RF connector to the
input of the device that is being applied externally. For more information on the funda-
mentals of the S-parameters and for application example, see also
1GP70: Using S-
Parameters with R&S®NRP-Z Power Sensors .
All R&S NRPxxTWG power sensors allow compensating for the influence of any 2-port
device between the signal source and the sensor input. As a result, the firmware can
calculate the power that the signal source actually delivers. Examples of such 2-port
devices include attenuators, matching pads, minimum-loss pads and waveguide adapt-
ers. One precondition for such compensation is that you provide a complete set of S-
parameter data for the 2-port device in the frequency range required by the application.
The S-parameters of the attenuator delivered with the R&S NRPxxTWG have been
measured by Rohde
& Schwarz. The results of the factory calibration, including an S-
parameter table that matches the delivered attenuator, are stored in the factory calibra-
Configuring Basic Measurement Parameters