R&S ZNB Series User Manual page 528

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R&S ZNB/ZNBT
Port Overview ← Port Cal Power
The dialog shows all source ports of the network analyzer. Each port is displayed with
the current "Power Result" at the input of the DUT (in dBm) and offset (i.e. the "Cal
Power Offet" in dB).
Configured external generators ("G1" ...) are included in the source port overview.
Remote command:
SOURce<Ch>:POWer<PhyPt>[:LEVel][:IMMediate]:OFFSet
SOURce<Ch>:POWer<PhyPt>:CORRection:LEVel:OFFSet
Channel Base Power ← Port Cal Power
Allows you to select between the channel base power P
Remote command:
SOURce<Ch>:POWer<PhyPt>[:LEVel][:IMMediate]:OFFSet
Port Power Offset ← Port Cal Power
Defines a port-specific offset to the
the port is equal to the "Channel Base Power" plus the "Port Power Offset".
If P
b
power varies across the sweep. Otherwise the port power is constant.
Remote command:
SOURce<Ch>:POWer<PhyPt>[:LEVel][:IMMediate]:OFFSet
SOURce<Ch>:POWer<PhyPt>:GENerator<Gen>:OFFSet
Cal Power Offset ← Port Cal Power
For power calibrations only: Specifies a gain (positive values) or an attenuation (nega-
tive values) in the signal path between the source port and the calibrated reference
plane. With a "Cal Power Offset" of n dB, the target power at the reference plane (cal
power) is equal to the actual output power at the port plus n dB. The "Cal Power Off-
set" has no impact on the source power.
Example: Use of an amplifier in the signal path
Assume that a DUT requires a constant input power of +25 dBm, and that the mea-
surement path contains an amplifier with a 30 dB gain. After a reset of the analyzer, the
channel power P
source port and a "Cal Power Offset" of +30 dB. Then the source power calibration
ensures that the constant input power of +25 dBm is maintained across the entire
sweep range. The actual output power of the analyzer is -5 dBm.
Notice that a power calibration with an appropriate "Cal Power Offset" can prevent
excess input levels at the DUT.
Remote command:
SOURce<Ch>:POWer<PhyPt>:CORRection:LEVel:OFFSet
SOURce<Ch>:POWer<PhyPt>:CORRection:GENerator<Gen>:LEVel:OFFSet
Reference Receiver Cal Power
Defines the source power settings the R&S ZNB/ZNBT uses to perform the first cali-
bration sweep of the source power calibration.
User Manual 1173.9163.02 ─ 62
is selected as "Channel Base Power", then for a power sweep the actual port
is -10 dBm. Select a "Port Power Offset" of +5 dB at the calibrated
b
and a fixed value of 0 dBm.
b
Channel Base Power The actual output power at
GUI reference
Cal softtool
528