R&S ZVB - Page 375

R&S
®
ZVA / R&S
®
ZVB / R&S
®
ZVT GUI Reference
Channel Menu
Operating Manual 1145.1084.12 – 30 360
 Abort Sweep stops the current sweep, e.g. in order to change the sweep settings.
 The calibration sweeps are performed according to the settings shown in the Source Cal Settings
panel below the list of calibrations. Modify Settings... opens the Modify Source Power Cal Settings
dialog to modify the essential settings of the subsequent calibration sweeps.
 Power Meter selects an external power meter that is used to measure the exact source power at
the calibration plane; see Power Meter Settings in the Power Calibration section. Power meters
(Pmtr1, Pmtr2, ...) must be configured in the System Configuration – External Power Meters
dialog before they appear in the list. This dialog can be opened directly with the Power Meter
Config button.
 Perform Verification Sweep after Cal enables or disables a verification sweep that the analyzer
performs after the source power calibration. The sweep is also displayed in the calibration sweep
diagram. Its purpose is to test the accuracy of the source power calibration after the final
correction data has been acquired. The final power calibration results are applied starting with the
first sweep after the verification sweep.
Remote control:
SOURce<Ch>:POWer<Pt>:CORRection:IMODulation:LTONe[:ACQuire]
SOURce<Ch>:POWer<Pt>:CORRection:IMODulation:UTONe[:ACQuire]
SOURce<Ch>:POWer<Pt>:CORRection:IMODulation:SPORts[:ACQuire]
SOURce<Ch>:POWer<Pt>:CORRection:IMODulation:RPORt[:ACQuire]
[SENSe<Ch>:]CORRection:POWer<port_no>:IMODulation:ACQuire
[SENSe<Ch>:]CORRection:POWer<port_no>:IMODulation:RPORt:ACQuire
Level Handling during Power Calibration
The figure below shows the signal flow in the test scenario where the lower tone from port 1 and the upper
tone from port 3 are combined using the directional coupler of port 3. In this scenario the directional
coupler introduces an attenuation (coupling loss) of typically 10 dB for the lower tone signal.
To compensate for the coupling loss and obtain upper and lower tone signals with equal power, modify the
source power settings for port 1:
1. Open the Intermodulation Distortion Measurement Power Calibration dialog and click Modify
Settings... – Modify Cal Power... for port 1 to open the Port 1 Power dialog.
2. Select a 10 dB Port Power Offset to increase the source power, compensating for the 10 dB
coupling loss.
3. Select a –10 dB Cal Power Offset to ensure that the calibrated power at the reference plane (Cal
Power) remains at the channel base power p
b
(Cal Power = p
b
+ Port Power Offset + Cal Power
Offset).