Agilent Technologies N4413A, User Manual

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Using the Multiport Test System
How to Characterize Active Devices
Chapter 3 58
How to Characterize Active Devices
Set the input power level using the source power and/or attenuator settings (N4413A and
N4414A only) to compensate for the expected gain of the DUT. Keep in mind the saturation
level of the DUT and the input power limits and damage level of the test set and analyzer.
Some system models have a provision for biasing the DUT through the test ports. In this case,
bias voltages are applied to the bias inputs on the rear of the test set.
Active Device Measurement Example
This example shows the characterization of a 27 dB gain amplifier with a +10 dBm
compression point. Measurements were made to show gain, isolation, and match.
The system was calibrated with the following Measurement Parameters (as shown below):
•
−
30 dBm output level (10 dBm source power, 10 dB of test set path loss, and 30 dB of
attenuation)
• Frequencies from 800 MHz to 1000 MHz with 5 MHz steps
The bias was set for 6 V
DC
directly on the power supply.