your position is our focus
The
following
SBAS
messages
are
supported,
in
accordance
to
standard
DO-229C:
Message
Type
Message
Content
Used
from
0(0/2)
Test
Mode
All
1
PRN
Mask
Assignment
Primary
2,
3,
4,
5
Fast
Corrections
Primary
6
Integrity
Primary
7
Fast
Correction
Degradation
Primary
9
GEO
Navigation
(Ephemeris)
All
10
Degradation
Primary
12
Time
Offset
Primary
17
GEO
Almanachs
All
18
Ionosphere
Grid
Point
Assignment
Primary
24
Mixed
Fast
/
Long
term
Corrections
Primary
25
Long
term
Corrections
Primary
26
Ionosphere
Delays
Primary
Table 37: Supported SBAS messages
–
a
class
Beta-1
equipment.
All
timeouts
etc.
are
chosen
for
the
En
Route
Case.
Do
not
use
this
equipment
for
tem
is
still
in
test
mode
time
en
does
not
ca
the
GEOs
from
all
but
the
EGNOS
system
should
be
disallowed,
using
the
PRN
Mask.
It
is
important
to
understand
that
while
EGNOS
is
in
test
mode,
anything
can
to
Note
e
SBAS
correction
data.
Note
This
ANTARIS
®
4
SBAS
implementation
is
–
in
accordance
with
standard
RTCA/DO-229C
safety
of
life
applications!
As
each
GEO
services
a
specific
region,
the
correction
signal
is
only
useful
within
that
region.
Therefore,
mission
planning
is
crucial
to
determine
the
best
possible
configuration.
The
different
stages
(Testmode
vs.
Operational)
of
the
various
SBAS
systems
further
complicate
this
task.
The
following
examples
show
possible
scenarios:
Example 1: SBAS Receiver in North America
At
the
time
of
writing,
the
WAAS
system
is
in
operational
stage,
whereas
the
EGNOS
sys
(ESTB).
Therefore,
and
especially
in
the
eastern
parts
of
the
US,
care
must
be
taken
in
order
not
to
have
EGNOS
satellites
taking
preference
over
WAAS
satellites.
This
can
be
achieved
by
Disallowing
Test
Mode
use
(this
inhibits
EGNOS
satellites
from
being
used
as
a
correction
data
source),
but
keeping
the
PRN
Mask
to
have
all
SBAS
GEOs
enabled
(which
allows
EGNOS
GEOs
to
be
used
for
navigation).
Example 2: SBAS Receiver in Europe
At
the
of
writing,
the
EGNOS
system
is
still
in
test
mode.
To
try
out
EGNOS
operation,
Testmode
usage
must
be
abled.
Since
the
WAAS
GEO
#122
can
be
received
in
the
western
parts
of
Europe,
but
since
this
GEO
rry
correction
data
for
the
European
continent,
happen
the
EGNOS
signals,
such
as
sudden
interruption
of
service
or
broadcast
of
invalid
or
inconsistent
data.
The
ANTARIS
®
4
GPS
receiver
makes
always
use
of
the
best
availabl
GPS
Modules
-
System
Integration
Manual
(SIM)
(incl.
Reference
Design)
Receiver
Description
GPS.G4-MS4-05007-A1
Page 106
