R&S ESR Series User Manual page 220

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R&S ESR
Setting
Margin
Position
Value
X-Axis:
Span setting
Scale mode
Scale
Y-Axis:
Scale unit
Scale mode
Limit type
In addition, the following functions are available for the limit line:
Defining a threshold
If the scaling of the y-axis is relative, you can define an absolute threshold value that
works as a lower limit for the relative limit values (see figure below).
► Enter a value in the "Threshold" field of the "Edit Limit Line" dialog box.
The function is especially useful for mobile radio applications provided the limit values
are defined in relation to the carrier power as long as they are above an absolute limit
value.
User Manual 1175.7068.02 ─ 12
Description
A fixed distance to the limit line.
Margins are not as strict as limits and belong to the valid value range, but viola-
tion is also indicated in the display.
Position of data point
Value of data point
●
"Hz" for span > 0 Hz
●
"s" for zero span
●
Absolute: The frequencies or times are interpreted as absolute physical
units.
●
Relative: In the data point table, the frequencies are referred to the cur-
rently set center frequency. In the zero span mode, the left boundary of the
diagram constitutes the reference.
Relative scaling is always suitable if masks for bursts are to be defined in
zero span or if masks for modulated signals are required for span > 0 Hz.
●
Linear
●
Logarithmic
Unit of the y-axis
●
Absolute: The limit values refer to absolute levels or voltages.
●
Relative: The limit values refer to the reference level (Ref Level). Limit val-
ues with the unit dB are always relative values.
●
Upper limit
●
Lower limit
Receiver Mode
Common Analysis Functions
217