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S:\Hp8960\E1960A GSM Mobile Test Application\A.04 Release\Reference_Manual\Chapters\prog_trig.fm
Triggering of Measurements
Triggering of Measurements
E1960A Operating Considerations
When the operating mode = active cell mode, Auto triggering sets the trigger source to Protocol. When the
operating mode = test mode, auto triggering sets the trigger source to RF Rise.
Description
Trigger Source Description
A measurement trigger causes hardware (for example, a sampler) to capture data which is used by a
measurement algorithm to produce a measurement result. The following table shows the trigger source
selections available to the user.
RF Rise Trigger Source: When RF rise triggering is selected, a measurement dependent threshold is used
to define the trigger point on the envelope of the signal being measured. The envelope amplitude must fall
below this threshold and remain there for a measurement-dependent period of time before the trigger is
armed. After the trigger is armed, a trigger will occur as the envelope amplitude increases and passes through
the threshold.
Protocol Trigger Source: When protocol triggering is selected, a data capture is triggered by a protocol
generated signal. The test set’s protocol engine knows when the DUT’s signal should be present and generates
a trigger signal for use by the measurement to trigger the data capture.
External Trigger Source: When external triggering is selected, the user supplies an external trigger signal
via the rear panel TRIG IN connector in order to trigger data capture. The trigger will occur on the rising edge
of this signal.
Immediate Trigger Source: When immediate triggering selected, the trigger occurs as soon as any
pre-trigger samples required by the measurement algorithm are taken. Data capture is triggered when the
measurement is initiated.
Auto Trigger Source: When auto triggering is selected, the test set automatically chooses the best trigger
source for that measurement. This trigger source setting is convenient because the measurement trigger
doesn’t need to be changed when switching parameters. Auto trigger source is the best choice for most users.
Table 3. Trigger Source choices
Trigger Source
Function
RF Rise
Generated from a change in the amplitude of the signal being measured.
Protocol
Generated from a specific data word in the mobile station’s transmission.
External
Generated from an external signal.
Immediate
Generated from measurement initiation.
Auto
The test set selects the trigger source optimized for a given measurement.
Summary of Contents for 8960 Series 10
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