ashtech DG14, Справочное руководство

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220 DG14 and DG16 Board & Sensor Reference Manual
SNW: SBAS Ephemeris Data
$PASHS,RAW,SNW,c1,s2
This command enables or disables the SBAS ephemeris data on port s1, where c1
is port A, B or C (optional port), s2 is ON or OFF.
The DG16 outputs the ephemeris data each time the IOD changes (at a maximum
of 2 minutes) with data for one satellite at each recording interval.
Example
Enter the following command to send the ephemeris data to port B.
$PASHS,RAW,SNW,B,ON
$PASHQ,SNW,[c1]
This command queries the current SBAS ephemeris data, 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,SNW
The response is one binary message per locked satellite in the format:
$PASHR,SNW,<SBAS Ephemeris data checksum>
Table 7.21 outlines the data string format.
Table 7.21. $PASHQ,SNW Response Structure
Field Bytes Content
char 1 IOD—Issue of data.
char 1 Accuracy.
long 4 t0—Ephemeris data reference time within the day
expressed in the SBAS time scale (seconds).
double 3*8 Satellite ECEF X, Y, Z coordinates (meters).
float 3*4 Satellite ECEF velocity X’, Y’, Z’ (m/s).
float 3*4
Satellite ECEF acceleration X”, Y”, Z” (m/s
2
).
float 4 aGf0—Time offset between satellite time scale and
SBAS system time scale (seconds).
float 4 aGf1—Time drift between satellite time scale and
SBAS system time scale (seconds).
long 4 tow—Time within week in GPS time scale when
SBAS ephemeris was received.