MSRA basics
R&S
®
FSWP-B1
28
User Manual 1177.5862.02 ─ 09
offline trigger that defines an additional offset to the capture offset. The data range that
is actually analyzed is referred to as the
analysis interval
.
The analysis interval is indicated in the window title bar for each evaluation, and can be
queried via remote control.
For secondary applications that do not allow you to restrict the evaluation range (e.g.
I/Q Analyzer, Modulation Analysis), the analysis interval is identical to the secondary
application data extract.
Trigger offset vs. capture offset
The beginning of the capture buffer is defined by the trigger event and the trigger off-
set. The trigger source is defined by the MSRA primary, which means that all channels
use the same trigger. However, each secondary application might need a different trig-
ger offset or a different number of pretrigger samples. Instead of a trigger offset, the
secondary applications define a
capture offset
. The capture offset is defined as an
offset to the beginning of the capture buffer
.
Thus, the beginning of the secondary application data extract is calculated as:
[time of trigger event] + [trigger offset] + [capture offset]
Note that while the trigger offset value may be negative, thus starting before the trigger
event, the capture offset may not. A negative capture offset would mean the secondary
application data would start before the first sample of the capture buffer. The (pre-)trig-
ger offset in the MSRA primary must be configured such that the required number of
pre-trigger samples for the secondary applications are available.
Analysis line
A frequent question when analyzing multi-standard radio signals is how each data
channel is correlated (in time) to others. Thus, an analysis line has been introduced.
The analysis line is a common time marker for all MSRA secondary applications. It can
be positioned in any MSRA secondary application or the MSRA primary and is then
adjusted in all other secondary applications. Thus, you can easily analyze the results at
a specific time in the measurement in all secondary applications and determine corre-
lations (e.g. cross-talk).
If the marked point in time is contained in the analysis interval of the secondary appli-
cation, the line is indicated in all time-based result displays, such as time, symbol, slot
or bit diagrams. By default, the analysis line is displayed, however, it can be hidden
from view manually. In all result displays, the "AL" label in the window title bar indicates
whether or not the analysis line lies within the analysis interval or not:
●
orange "AL"
: the line lies within the interval
●
white "AL"
: the line lies within the interval, but is not displayed (hidden)
●
no "AL"
: the line lies outside the interval
Multi-standard analysis