NavCom Sapphire Rev.J - Manual (Page 360)

Sapphire Technical Reference Manual Rev. J
360
2.100 SATSUSEDB (Binary)
SF-3050 Sapphire SF-3040
This message describes all the tracked PRN’s and any reasons why a PRN is not used in the
Code and RTG navigation. Table 188 lists the body of the SATSUSEDB message. The table
starts with a single byte showing the count of entries in the table. For each count, the table
follows sequentially with an entry for each. Each PRN is followed by the failure bit-map
associated with that PRN.

There are eight bytes per PRN. This means that the message is (#PRN) * 8, plus
one byte for the leading count byte.
Table 188: SATSUSEDB Binary Message Data
Data Item Data Type
Number of satellites reported failures in the message U08
PRN for the first satellite with failures U16
Bit-map of Failure Condition Bitmap (see below) U08(6)
…
PRN for the last satellite with failures U16
Bit-map of Failure Condition Bitmap (see below) U08(6)
Table 189 shows the failure conditions encoded for the Failure Condition Bitmap for each
satellite. The conditions are listed in the order they appear in the bitmap from the MSB. There is
a total of 6 bytes in the bitmap, resulting in 48 bits. If a bit is set (equal to 1), the corresponding
failure condition has occurred for the satellite.
Table 189: Failure Conditions
MSB Failure Condition Enum Failure Condition
1 FAILED_CP_DISCONTINUITY
Carrier Phase discontinuity
detected
2 FAILED_HALF_CYCLE
Half cycle ambiguity not
resolved
3 FAILED_RESID
Failed residual edit in
resid_edit
4 FAILED_MEASTIME
Wrong measurement time in
MeasProc
5 FAILED_DUPPRN Duplicate PRN
6 FAILED_NOL1 L1 marked invalid
7 FAILED_EXSMOOTH
Slip detected in
MeasSmooth()
8 FAILED_ELEV Elevation below mask
9 FAILED_L1CYCLE Cycle slip detected on L1
Table c
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