Keysight N7744A, Руководство пользователя

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How to Set the Reference Value to the Current Power Value
In addition to entering a new reference value, you can change the
reference value to the current power value from the N77xx Viewer or
by programming.
This takes the input power level and stores it as the reference. Setting
the reference only affects results returned in dB.
The power value in dBm or Watts is stored as the reference, that is:
REF = P
measured
where,
REF is the reference, and
P
measured
is the absolute power level (see “How to Set the Calibration
Offset” on page 49 ).
How to Reference Another Power Measurement Port
You can use the reference mode to reference to another port’s current
power level. If you choose this mode, the reference of the port
continuously updates to the current power value measured by the other
port.
The following equations describe how the power in dB is calculated if
you reference another port:
P
dB
= P
measuredA
(dBm) - P
measuredB
(dBm) - REF(dB)
or
where:
P
dB
is the relative power,
P
measuredA
is the absolute power level (see “How to Set the Calibration
Offset” on page 49 ) measured by the current port, and
P
measuredB
is the absolute power level (see “How to Set the Calibration
Offset” on page 49 ) measured by the port you choose to reference, and
REF is the reference level in decibels (dB).
2
Power Measurement
50 Keysight N774x Series