Measuring Relative Power; Relative Power Example - Keysight 53147A Operating And Programming Manual

Measuring Relative Power

You can measure the difference in power from one measurement to another or
between two separate input signals using the Relative Power function.

Relative Power Example

Press the Shift key, and then press the Rel Pwr (POWER METER: Offset On/Off)
key. The Shift annunciator activates when you press the Shift key. When you
press the Rel Pwr key, the Shift annunciator disappears, and the Rel Pwr
annunciator at the left side of the display activates. At the same time, the Power
Meter saves the power measurement it was displaying at the time you pressed the
Rel Pwr key, and it computes and displays the difference in power between the
stored measurement and all subsequent measurements until the relative power
function is deactivated.
When the Power Meter is set to measure power in dBm, relative power is
NOTE
expressed in dB. When the Power Meter is set to measure power in Watts,
relative power is expressed as a percentage (%).
You can also use the Relative Power function to measure the difference in power
between two different signals. To do this, activate the Relative Power function, as
described in the previous paragraph, disconnect the signal to the power head
(sensor), and then connect the second signal to the same power head. The value
displayed when the Power Meter acquires the second signal is the power
difference between the two signals.
Keysight 53147A/148A/149A Operating and Programming Guide
Ch 12
Rel Freq
Rel Pwr
Operating Your Instrument 2
109