How To Set The Power Unit - Keysight N7744A User Manual

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Power Measurement

How to Set the Power Unit

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How to Set the Number of Digits
When the power is displayed with the Web Interface or the Viewer
program, you can set the maximum number of digits that are used in
power measurement. This is the maximum number of digits after the
decimal point.
The Power Unit setting allows you to select either W, dBm or dB as the
units in which power is displayed or returned. For returning large
amounts of logged data, the fastest data transfer is achieved using W
units.
What are the Power Units?
Watts (W) are the SI unit for power measurement.
You can also measure power in dB or dBm. Values returned in these
units are derived from measurement in Watts.
By selecting dBm, the following calculation is made:
Where,
P is the power value returned in dBm, and
dBm
P is the input signal level in Watts.
input
Power, in units of dBm, is measured relative to 1 mW. It is an absolute
power measurement.
Power, in units of dB, is measured relative to a particular reference
power value. For information on selecting this reference value, see How
to Input a Reference Level.
The following calculation is made:
Where,
P is the power value returned in dB,
dB
P is the input signal level in Watts, and
input
Keysight N774x Series