R&S ZNL, Руководство пользователя

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VNA GUI reference
R&S
®
ZNL/ZNLE
513 User Manual 1178.5966.02 ─ 19
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
b
and a fixed value of 0 dBm.
Remote command:
SOURce<Ch>:POWer<PhyPt>[:LEVel][:IMMediate]:OFFSet
Port Power Offset ← Port Cal Power
Defines a port-specific offset to the Channel Base Power The actual output power at
the port is equal to the "Channel Base Power" plus the "Port Power Offset".
If P
b
is selected as "Channel Base Power", then for a power sweep the actual port
power varies across the sweep. Otherwise the port power is constant.
Remote command:
SOURce<Ch>:POWer<PhyPt>[:LEVel][:IMMediate]: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
b
is -10 dBm. Select a "Port Power Offset" of +5 dB at the calibrated
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
Reference Receiver Cal Power
Defines the source power settings the R&S ZNL uses to perform the first calibration
sweep of the source power calibration.
In this first sweep, the power meter reading is used to calibrate the reference receiver
of the calibrated port. The following calibration sweeps are based solely on the refer-
ence receiver (see
"Calibration procedure" on page 274).
By default, the "Reference Receiver Cal Power" is set to the resulting Port Cal Power .
However, the accuracy of the source power calibration depends on the power meter's
measurement accuracy. Therefore it is advantageous to select a "Reference Receiver
Cal Power" at which the power meter provides maximum accuracy.
Cal softtool