Agilent Technologies 86140B Series, Руководство пользователя

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3-41
Function Reference
Marker Setup
Peak Excursion
Determines (in dB) which side modes are included in the measurements. To
be accepted, each trace peak must rise, and then fall, by at least the peak
excursion value about a given spectral component. The default value is 3 dB.
Setting the value too high may result in not identifying a side mode. Setting
the value too low may cause unwanted responses, including noise spikes, to be
identified. Use the Marker Setup panel to change the peak excursion value.
Changing the peak excursion . The peak searches may not recognize valid
signals near the noise floor when the peak excursion definition is less than 3
dB. Thus, before performing peak searches on signals near the noise floor,
reduce the peak excursion value. However, reducing the excursion value often
causes peak searches to identify noise spikes. To avoid this misidentification,
use video averaging or video filtering to reduce the noise floor variance to a
value less than the peak excursion definition.
Pit Excursion
Sets the pit excursion value for the marker search routines.
The pit excursion value is used to determine whether or not a local minimum
in the trace is to be considered a pit. To qualify as a pit, both sides of the local
minimum must rise by at least the pit excursion value.
Peak excursion criteria
Pit excursion criteria