Rohde & Schwarz EVSF1000, User Manual

Page: 135 / 295

GBAS/SCAT-I Mode (Options R&S EVSG-K4/-K5)
R&S
®
EVSF1000
135 User Manual 1178.6410.02 ─ 05
8.6 Message XML Interface
The R&S EVSG-K4 receives and analyzes VDB GBAS transmissions according to
ICAO AN10 Vol1 [3] and RTCA DO-246 [1]. Analysis includes physical measurement
values such as level, frequency or EVM. The results can be displayed or recorded. A
bitstream is also provided with each transmission (
burst ). The bitstream contains the
digital information required by a GPS receiver for its calculations. To display this infor-
mation in human-readable format, the bitstream needs to be interpreted as described
in the document.
The R&S EVSG GBAS/SCAT-I option provides a special parser that transforms the
data efficiently, controlled by a set of XML files. The XML files contain the rules and
data definitions for conversion and are loaded during runtime. The converted, human-
readable data is then displayed in the "Message" view (see
Chapter 8.4.5, "Message
View" , on page 129).
You can edit the XML control files with any text editor to obtain specific outputs, for
example, or to accomodate the output to changes in the specifications. However, a
good knowledge of the ICAO AN10 Vol1 [3] and RTCA DO-217 [2] specifications is
essential to understand the transformation process.
The R&S EVSF1000 provides a default set of xml files for an initial message type defi-
nition. These files are stored internally on the instrument. You can export the files to a
USB storage device and import the customized files back to the R&S
EVSF1000 (see
"Import xml" on page 134).
To customize the "Message" view results
1. Connect a USB storage device to the R&S EVSF1000.
2. Select [Config] > "Export xml".
The required file structure and files are stored on the storage device.
3. Edit the files as required. See the descriptions below for more information.
4. Select [Config] > "Import xml".
The edited files are stored on the R&S EVSF1000.
5. Select [Config] > "DEC DEF" > Custom.
The R&S EVSF1000 decoder uses the edited, imported message definition and
displays the defined results in the "Message" view.
● General Processing ...............................................................................................136
● Output Elements and Control Elements ................................................................137
● XML File Format Description .................................................................................140
● Format Description of Elements ............................................................................142
● Output Elements ................................................................................................... 142
● Control Elements ...................................................................................................150
● Auxiliary Elements .................................................................................................154
Message XML Interface