Receiver Mode
R&S
®
ESR
217
User Manual 1175.7068.02 ─ 12
Setting
Description
Margin
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
Position of data point
Value
Value of data point
X-Axis:
Span setting
●
"Hz" for span > 0 Hz
●
"s" for zero span
Scale mode
●
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.
Scale
●
Linear
●
Logarithmic
Y-Axis:
Scale unit
Unit of the y-axis
Scale mode
●
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.
Limit type
●
Upper limit
●
Lower limit
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.
Common Analysis Functions