RTX RTX2018, Руководство пользователя

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Date: 09-May-2019
Product name RTX2018
File : RTX2018 User Manual 1.0.docx Ref.: FHA Page: 25 of 34
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Unauthorized copying is not allowed. The information in this document is believed to be correct at the time of writing. RTX A/S
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The evaluation window is adjusted the same way as the capture time. The evaluation window
will be also be changed depending of the selected slot type.
The range for the evaluation window is 0 to 1000 us.
5.3.4
B0 Search
The time reference for the evaluation has two options:
•
Trigger Event (same as for the Capture Time)
•
b0 Search
The “b0 Search” field can be enabled with the small slider . In this case the analysis
program will search for a sync word within the capture signal.
The sync word is selected from a dropdown menu. Two sync words are available - either a PP
(Portable Part) or FP (Fixed Part) sync word.
If the analysis finds this sync word within the received signal, the time reference for the
evaluation window will be the first symbol in the sync word (see
Figure 14
below).
The time unit for the evaluation window will also change to symbol periods in this case.
Expected Power
Trigger Offset
Power
Time
Trigger Gap (>10 us)
Capture Time Start [us]
Trigger Point
PP S A B X Z
b0
Evaluation Window
Eval. Start [sym]
Evaluation Window Stop [sym]
With b0 Search
Capture Time Stop [us]
Figure 14. Capture and evaluation timing with b0 search.
5.4
Modulation
In the “ TX PSK ” tab there is also a dropdown menu to select which of the 3 different PSK
modulation schemes is to be used:
•
π/2 -DBPSK
•
π/4 -DQPSK
•
π/8 -D8PSK