Gating - Agilent Technologies FieldFox N9913A User Manual

Gating

Perhaps the most beneficial feature of Time Domain transform is the Gating
function. When viewing the Time Domain response of a device, the gating
function can be used to "virtually" remove undesired responses. You can then
simultaneously view a frequency domain trace as if the undesired response did
not exist. This allows you to characterize devices without the effects of external
devices such as connectors or adapters.
Gating is best performed while viewing a Time Domain trace. Then, either disable
Transform, or separately view a frequency domain trace to see the trace with the
gated effects removed.
NOTE When a discontinuity in a test device reflects energy, that energy will not reach
subsequent discontinuities. This can "MASK", or hide, the true response which
would have occurred if the previous discontinuity were not present. The Gating
feature does NOT compensate for this.
The following image shows how gating can affect measurement results.
All 4 traces show the same S11 measurement.
Trace 1 shows the frequency response without gating enabled.
Trace 2 shows the transform response without gating enabled.
Trace 3 shows the transform response with gating enabled.
Trace 4 shows the frequency response with gating enabled.
How to make Time Domain Gating settings
 Press Measure 4
 Then
 Then
 Then choose from:
Time Domain - Option 010
Transform
Gating
On
Gating is being performed.
o
Off
Gating is NOT being performed.
o
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