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DOC 6501_Release V
ATS-6501 Users Guide
177
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Manual: Manual survey mode is for static applications in which the precise position of
the GPS antenna is known to less than a meter. In this mode, the system uses the user
specified settings for position given by
settings gps:positioning:manual_position
. This
is the mode to use if an AUTO survey was done and the RINEX observation file was
post-processed to determine a precise position. This mode provides the greatest level
of timing performance.
•
Dynamic: Dynamic positioning mode is for applications in which the GPS antenna
may be moving such as on an aircraft. The position of the antenna is never "fixed" by
the instrument since it assumes the antenna is mobile. This is the least accurate mode
in terms of timing performance.
The current GPS position being used by the system can be viewed using
status
gps:position
. Whether or not the position is 'fixed' depends on whether the instrument has
set the GPS antenna to a static value. This is done either at the end of the auto survey
period or when the user sets the GPS antenna position manually. The position_mode
setting is not ever changed by the instrument and thus if the system settings are saved in
AUTO mode then the instrument will begin a new position survey if the instrument is
restarted.
WARNING:
The position given by the
status gps:position
command is only a useful
diagnostic and is not intended to be used as a precise position of the GPS antenna for data
analysis purposes. For collecting precise GPS data the realtime GPS output port (1135)
should be used.
See also: position_period, latitude, longitude, altitude, log
Usage:
position_mode < auto | manual | dynamic >
Command Example:
ATS-6501>position_mode auto
Query:
ATS-6501>settings gps:positioning:mode
auto
position_period:
Description:
Sets the length of time to use for auto-surveying the GPS antenna position.
At the end of the survey period the position of the GPS antenna is 'fixed' to the average
GPS antenna location determined during the survey period and a RINEX observation file is
created (see 'help position_mode' for a more complete description).
A minimum of 2 hours should be used for auto-surveys but 4-6 hours is recommended and
12 hours (maximum) provides the best solution if time allows. The amount of time
remaining in an auto-survey is given by the
status gps:auto_positioning
command and is
reset every time the instrument enters the auto-survey mode. Therefore, if you want to
restart an auto-survey you can change the position mode to dynamic and then back to auto.