AM/PM (Component Test)

Menu Path: Trace > Data > Component Test > Linearity > Channel N > AM-PM

The AM/PM trace shows the channel's output phase versus its input amplitude: the response-minus-stimulus phase (degrees) plotted against the stimulus magnitude (Vpk). The trace is computed from the channel's IQ Ref (stimulus) and IQ Meas (response) signals. For a phase-linear channel the result is a flat line; amplitude-dependent phase shift appears as curvature.

The trace includes a least-squares polynomial fit whose order is set by the Polynomial Order control (default 5). The fit coefficients per channel are reported in the Linearity Summary table.

This trace is only computed when Computation Mode = Statistical, and requires phase compensation to be enabled; otherwise it shows no data.

See Also

AM/AM

Linearity Summary

Available Trace Data