Specifications

Innovative

Applications

Fast and accurate gain

compression versus

frequency measure-

ments of amplifiers

and converters

(Option 086)

Gain compression measurement challenges

• Characterizing ampliﬁer or frequency converter compression over its operating frequency

range requires measurements at many frequency and power points, so setting up the

measurements, calibration, and data manipulation takes a lot of time and effort

• A variety of errors degrade measurement accuracy, such as mismatch between the test

port and the power sensor and DUT during absolute power measurements, and using linear

S-parameter error correction in nonlinear compression measurements

PNA-X gain compression application (GCA) provides:

• Fast and convenient measurements with SMART Sweep

• Highly accurate results using a guided calibration that provides power and

mismatch correction

• Complete device characterization with two-dimensional (2D) sweeps, with the choice

of sweeping power per frequency, or sweeping frequency per power

• Flexibility with a variety of compression methods—compression from linear gain, maximum

gain, X/Y compression, compression from back-off, or compression from saturation

Frequency

Gain

Compression

point

Frequency

Gain

Compression point

Iteration point

A network analyzer is commonly used for gain compression

measurements by performing power sweeps at multiple CW

frequencies. The PNA-X’s GCA makes it easy to characterize

compression over the DUT’s operating frequency range with

extreme speed and accuracy, and a simple setup.

Instead of a linear power sweep with many points, GCA’s

SMART Sweep uses an adaptive algorithm to ﬁnd the desired

compression point at each frequency with just a few power

measurements, thus signiﬁcantly reducing test times.

Complete device response to 2D sweeps—gain versus frequency

and power—can be extracted for device modeling.

Using only power correction, incident

power at compression point exhibits

large ripple due to DUT mismatch

Measurement ripple is reduced with GCA

by using power and mismatch correction