Novatel OM-20000041 사용자 설명서
D
Logs summary
MiLLennium GPSCard Software Version 4.50 Command Descriptions Manual Rev 1
153
DOPA/B
Dilution of Precision
The dilution of precision data is calculated using the geometry of only those satellites that are currently being
tracked and used in the position solution by the GPSCard and updated once every 60 seconds or whenever a change
in the constellation occurs. Therefore, the total number of data fields output by the log is variable, depending on
the number of
tracked and used in the position solution by the GPSCard and updated once every 60 seconds or whenever a change
in the constellation occurs. Therefore, the total number of data fields output by the log is variable, depending on
the number of
SV
s tracking. Twelve is the maximum number of
SV
PRN
s contained in the list.
NOTE:
If a satellite is locked out using the
LOCKOUT
command, it will still be shown in the
PRN
list, but is
significantly deweighted in the
DOP
calculation.
DOPA
Structure:
Example:
$DOPA,637,512473.00,2.9644,2.5639,2.0200,1.3662,1.4880,6,18,6,11,2,16,19
*29[CR][LF]
*29[CR][LF]
$DOPA
week
seconds
gdop
pdop
htdop
hdop
tdop
# sats
prn list
*xx
[CR][LF]
Field #
Field type
Data Description
Example
1
$DOPA
Log header
$DOPA
2
week
GPS week number
637
3
seconds
GPS seconds into the week
512473.00
4
gdop
Geometric dilution of precision - assumes 3-D position and receiver clock offset (all
4 parameters) are unknown
4 parameters) are unknown
2.9644
5
pdop
Position dilution of precision - assumes 3-D position is unknown and receiver clock
offset is known
offset is known
2.5639
6
htdop
Horizontal position and time dilution of precision.
2.0200
7
hdop
Horizontal dilution of precision.
1.3662
8
tdop
Time dilution of precision - assumes 3-D position is known and only receiver clock
offset is unknown
offset is unknown
1.4880
9
# sats
Number of satellites used in position solution (0-12)
6
10...
prn list
PRN list of SV PRNs tracking (1-32), null field until first position solution available
18,6,11,2,16,
19
19
variable
*xx
Checksum
*29
variable
[CR][LF]
Sentence terminator
[CR][LF]