ashtech DG16 Reference Manual page 180

If $PASHS,SUI, OFF is sent the usage indicator in the SAT message will be U for
used or - for not used. If $PASHS,SUI,ON is sent the usage indicator in the SAT
message will be U for used or one of the letters listed in Table 6.53 in the SAT
column.
Table 6.53. MCA Good/Bad Flags and SAT Messages When SUI is ON
MCA good/
SAT
bad Flag
24 U
23 U
22 -
21 M
20 S
19 H
18 B
17 Z
16 D
15 J
14 R
13 I
12 L
11 G
10 V
09 N
08 K
07 P
02 O
01 E
160
Used and position computed
Used and position not computed
RESERVED
Satellite NOT used because of low elevation
Satellite NOT used because the pseudo-range is not settled (transient is not
over)
Satellite NOT used because marked 'unhealthy' in ephemeris
Satellite NOT used because of bad URA (or some accuracy problem indicated in
navigational data)
Satellite NOT used because marked 'unhealthy' in almanac
Satellite NOT used because differential corrections are old or invalid
Satellite NOT used because big code outlier was detected
Satellite NOT used because RAIM or some other algorithm detected a pseudo-
range bias
Satellite NOT used because satellite disabled by external command SVP,USP)
Satellite NOT used because Signal To Noise Ratio is less than Mask
Satellite NOT used because it's possibly a ghost satellite
Satellite NOT used because computed satellite coordinates are suspicious
Satellite NOT used because satellite true number unknown (for modes, where we
need the true satellite number
Satellite NOT used because it was disabled by RTK engine (N/A in DG16)
Satellite NOT used because no full range is available
Satellite NOT used because of some other case
Satellite NOT used because no navigational data (ephemeris) is available
DEFAULT SETTING
SUI— 0
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