Rohde & Schwarz EVSG1000, User Manual

Page: 143 / 311

GBAS/SCAT-I Mode (Options R&S EVSG-K4/-K5)
R&S
®
EVSG1000
143 User Manual 1178.6227.02 ─ 04
● Output Elements ................................................................................................... 149
● Control Elements ...................................................................................................157
● Auxiliary Elements .................................................................................................161
7.5.1 General Processing
The parser in the R&S EVSG GBAS/SCAT-I application uses the first message control
xml file as instructions for processing. As input, it receives a bitstream from the GBAS
burst in the input signal.
The general process of interpreting the bitstream consists of the following steps:
1. The parser applies the first instruction on the leading bits of the bitstream, which
usually produces a value or text as output.
2. The parser applies the next instruction on the subsequent bits of the bitstream.
As a result, either an output is produced, or further instructions are provided. Fur-
ther instructions can be provided in additional xml files, or depend on the current
bitstream value, or on a previous value (see
"Control elements" on page 145).
3. The parser continues to process the instructions as defined in the xml file, applying
them to the subsequent, not-yet-processed bits of the bitstream.
4. When the end of the last xml file has been processed, the parser stops.
The converted, human-readable data is displayed in the "Message" view.
Message XML Interface