SXBlue II GPS Series Technical Reference Manual
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The following table describes the ARM status.
ARM Status
Field
Description
01
GPS lock
02
DGPS valid data
04
The ARM processor has
lock
08
DGPS solution
10
DGPS solution is good
20
Not used
40
Not used
An example of the NavCondition is presented in the following table for the 179889A value.
NavCondition
Field
Description
A
The number of satellites with lock and carrier phase
9
The number of satellites with ephemeris received
8
The number of satellites with healthy ephemeris
8
The number of satellites that are tracked, have an
ephemeris, which is healthy, and are above the elevation
mask
9
The number of satellites above the elevation mask
7
The number of satellites with differential
1
The number of satellites with no differential
4.11 RAIM Command and Message
RAIM stands for Receiver Autonomous Integrity Monitoring. RAIM is a GPS integrity
monitoring scheme that uses redundant ranging signals to detect a satellite malfunction that
results in a large range error. The SXBlue II GPS uses RAIM to alert users when errors have
exceeded a user specified tolerance. RAIM is available for the SBAS applications.
4.11.1
$JRAIM Command
This command allows you to set the parameters of the RAIM scheme that affects the output
of the $PSAT,GBS message. This command has the following structure:
$JRAIM,HPR,probHPR,probFALSE<CR><LF>
Where:
Variable
Description
HPR
Horizontal Protection Radius (HPR). You will receive notification in the
$PSAT,GBS message that the horizontal error has exceeded this amount. The
acceptable range for this value is 1 to 10,000 meters. The default is 10 meters.
