Common Analysis and Display Functions
R&S
®
FSW
525
User Manual 1173.9411.02 ─ 19
●
The y unit of the limit line has to be identical to the current setting with the excep-
tion of dB based units; all dB based units are compatible with each other.
Validity
Only limit lines that fulfill the following conditions can be activated:
●
Each limit line must consist of a minimum of 2 and a maximum of 200 data points.
●
The frequencies/times for each data point must be defined in ascending order;
however, for any single frequency or time, two data points may be entered (to
define a vertical segment of a limit line).
●
Gaps in frequency or time are not allowed. If gaps are desired, two separate limit
lines must be defined and then both enabled.
●
The entered frequencies or times need not necessarily be selectable in R&S
FSW.
A limit line may also exceed the specified frequency or time range. The minimum
frequency for a data point is -200 GHz, the maximum frequency is 200 GHz. For
the time range representation, negative times may also be entered. The allowed
range is -1000 s to +1000 s.
Fig. 7-16: Example for an upper limit line
Limits and Margins
Limit lines define strict values that must not be exceeded by the measured signal. A
margin
is similar to a limit, but less strict and it still belongs to the valid data range. It
can be used as a warning that the limit is almost reached. The margin is not indicated
by a separate line in the display, but if it is violated, a warning is displayed. Margins are
defined as lines with a fixed distance to the limit line.
To check the signal for maximum levels you must define an
upper limit
, whereas to
check the signal for minimum levels you must define a
lower limit
.
Limits can be defined relative to the reference level, the beginning of the time scale, or
the center frequency, or as absolute values.
Display and Limit Lines
