Rohde & Schwarz EVSG-B1, User Manual

Page: 194 / 418

GBAS/SCAT-I Mode (Options R&S EVSG-K4/-K5)
R&S
®
EVSG1000
194 User Manual 1178.6227.02 ─ 06
● Format Description of Elements ............................................................................200
● Output Elements ................................................................................................... 200
● Control Elements ...................................................................................................208
● Auxiliary Elements .................................................................................................212
6.5.1 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 196).
3. The parser continues to process the instructions as defined in the XML file, apply-
ing 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