Agilent Technologies 8719D, User Manual

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6-83. Diagram of Compression
Figure 6-84 illustrates a simultaneous measurement of gain compression and amplifier output
power as a function of input power.
Figure 6-84. Gain Compression Using Power Sweep
In a compression measurement it is necessary to know the RF input or output power at a
certain level of gain compression. Therefore, both gain and absolute power level need to be
accurately characterized. Uncertainty in a gain compression measurement is typically less than
0.05 each input channel of the analyzer is calibrated to display absolute power.
Metering the Power Level
When you are measuring a device that is very sensitive to absolute power level, it is important
that you accurately set the power level at either the device input or output. The analyzer
is capable of using an external HP-IB power meter and controlling source power directly.
6-85 shows a typical test configuration for setting a precise leveled input power at the
device input. For more information on power meter calibration, refer to Chapter 5,
Measurement Results”
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