How Does It Work - Agilent Technologies 89410A Operator's Manual

Gating Concepts

How Does it Work?

The analyzer collects a record of data the duration of which is defined by main
length, and the position of which, relative to the trigger, is defined by [ main delay ].
After the main time data has been acquired, the analyzer isolates a portion of the
main data as the gate record. The duration and position (relative to the start of the
main record) of the gate are determined by [ gate length ] and [ gate delay ] respectively.
The gate record is then processed as the analyzer's time record. That is, spectrum,
frequency response, coherence, and correlation displays are based on the gate
record.
To control time gating, you define the following parameters:
l
Trigger setup (if any)
l
[ main delay ] (this corresponds to trigger delay)
l
[ main length ]
l
[ gate delay ]
l
[ gate length ]
After you have acquired main time data, you may reposition or resize the gate
without obtaining new main time data. The analyzer will automatically recompute
and redisplay the data contained in the modified gate record.
21 - 4