ashtech DG14, Справочное руководство

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206 DG14 and DG16 Board & Sensor Reference Manual
unsigned long
GpsNavFlags 4 Each bit is a “GPS Nav Flag” for a GPS satellite. The most
significant bit corresponds to PRN 32. When navigation data is
collected from a GPS satellite, a GPS Nav Flag bit is set for any
of the following reasons:
• User Range Accuracy (URA) Flag (“accuracy alert”, bit 18 of
the Hand-Over-Word (HOW)) is set (ref. paragraph 2.4.2.2 of
GPS SPS Signal Specification);
• Failure of parity on 3 successive words of the navigation data;
• All data bits in subframe 1, 2 or 3 are 0’s;
• Default navigation data (alternate 1’s and 0’s) is being
transmitted in words 3 through 10 of subframe 1, 2 or 3 for
that satellite (ref. paragraph 2.4.1.3 of GPS SPS Signal
Specification).
unsigned long
GloNavFlags 4 Each bit is a “GLONASS Nav Flag” for a GLONASS satellite. The
most significant bit corresponds to PRN 32, thus bit 23
corresponds to PRN 24. When navigation data is collected from a
GLONASS satellite, a GLONASS Nav Flag bit is set for any of the
following reasons:
• A parity error on three successive lines of the navigation data;
• Ephemeris time offset (time scale shift) equals zero;
• All three components of the satellite ephemeris coordinates or
velocity vector equal zero;
• All data bits in a string of any frame 1, 2, 3, 4 or 5 are 0’s;
unsigned long
GpsExcSats 4 Each bit is a “GPS Exclude Flag” for a GPS satellite. The most
significant bit corresponds to PRN 32. When a GPS satellite has
been excluded from being used to compute position, its
corresponding GPS Exclude Flag bit is set.
unsigned long GloExcSats 4 Each bit is a “GLONASS Exclude Flag” for a GLONASS satellite.
The most significant bit corresponds to PRN 32, thus bit 23
corresponds to PRN 24. When a GLONASS satellite has been
excluded from being used to compute position, its corresponding
GLONASS Exclude Flag bit is set.
Checksum 2 integer
Total Characters 42
Table 7.10. $PASHR,MIS Response Format for Message Type 1
Field
Length
(bytes)
Content