Keysight N9912A - Gating; How to Make Time Domain Gating Settings; Start, Stop, Center, and Span Gate Times; Gating Type

6- 10 Keysight N9912-90001 User’s Guide
Time Domain – Option 010
Gating
6-
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.
How to make Time Domain Gating settings
—Press Measure 4 .
—Then Transform
.
—Then Gating
.
— Then choose from:
— On
Gating is being performed.
— Off Gating is NOT being performed.
Start, Stop, Center, and Span Gate Times
These settings specify the time in the trace to be gated (in or out). The gate
times can be specified using either Start and Stop or Center and Span.
—Press Gating Start Stop
.
— A settings table appears that allows you to navigate and select the
following settings. These settings are made exactly like those made on the
Transform Settings table. Learn how in “Transform Settings Table” on
page 6-4.
Gating Type
This setting defines the type of filtering that will be performed for the gating
function. The gate start and stop flags on the display point toward the part of
the trace you want to keep.
Choose from the following:
— Bandpass
KEEPS the responses within the Gating Start and Stop times.
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.