ashtech DG14, Справочное руководство

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218 DG14 and DG16 Board & Sensor Reference Manual
SNV: Satellite Ephemeris Data
$PASHS,RAW,SNV,c1,s2,[f1]
This command enables or disables the ephemeris data (SNV) messages, where
c1 is port A, B or C (optional port), s2 is ON or OFF, and f1 is the optional numeric
output interval setting supporting a range of 0.05 to 999 seconds, depending on
the measurement update rate option installed.
Ephemeris data is output once every 15 minutes or each time the IODE changes, whichever comes
first, with one satellite output at each recording interval (RCI).
$PASHQ,SNV,[c1]
This command queries for ephemeris data from each satellite currently being
tracked by the receiver, where c1 is the optional port designator for the response.
If a port is not specified, the receiver sends the response to the current port.
$PASHR,SNV
One SNV message is output for each satellite being tracked. This message is not
output unless the receiver is locked on at least one satellite. SNV messages contain
some of the same data found in the SAL message, but also contains clock correction
parameters and harmonic correction parameters. The message is output in the
format:
$PASHR,SNV,<Ephemeris data checksum>
Table 7.20 outlines the data string format.
Table 7.20. $PASHQ,SNV Response Structure
Field Bytes Content
short wn 2 GPS week number
long tow 4 Seconds of GPS week
float tgd 4 Group delay (seconds)
long aodc 4 Clock data issue
long toc 4 Clock data reference time in seconds
float af2 4 Clock correction (sec/sec2)
float af1 4 Clock correction (sec/sec)
float af0 4 Clock correction (sec)
long aode 4 Orbit data issue
float deltan 4 Mean anomaly correction (semicircles/sec)