Jackson Labs Mini-JLT GNSS, Руководство пользователя

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Mini-JLT GNSS™
User Manual
22 © 2017 Jackson Labs Technologies, Inc.
If the Timing Mode is OFF, the receiver will act as a regular GNSS receiver in 3D mobile mode. This
mode has to be chosen if the unit is used with a moving antenna.
If the Timing Mode in ON, the timing features of the GNSS receiver are enabled. At power-up, the
Hold position stored in NVRAM will be sent to the GNSS receiver and will be used as the reference.
In order to use this mode, the receiver position must be known as exactly as possible. Errors in the
Hold position will translate into time errors depending on the satellite constellation.
The Hold position can be set manually by the user or can be the result of a position Auto Survey
executed by the GNSS receiver.
If the Timing Mode is set to RSTSURV, the GNSS receiver will start an Auto Survey every time the
unit is powered-on and following the Survey sequence, the GNSS receiver will run with the timing
features enabled. Once in Position Hold mode, the antenna location should be held completely
stationary.
3.3.21 GPS:SURVey ONCE
This command starts a Survey. At the end of the Survey, the calculated Hold position will be stored
in NVRAM. The Survey parameters can be set with the command
GPS:SURVey:DURation and
GPS:SURVey:VARiance
3.3.22 GPS:SURVey:DURation <sec>
This command sets the Survey minimal duration.
3.3.23 GPS:SURVey:VARIANCE <mm
2
>
This command specifies the minimum variance of the average position computed during the Survey.
This minimum value is used as a threshold under which the GNSS receiver can stop the Survey. The
GNSS receiver will stop the Survey when the minimal duration has been reached and the variance of
the average position is under the specified minimum variance.
3.3.24 GPS:HOLD:POSition <cm, cm, cm>
This command allows the user to specify manually the exact position of the unit. This command will
overwrite the Hold position in NVRAM. Subsequent Survey will overwrite also the Hold position.
The Hold position is stored in ECEF coordinates
3.3.25 GPS:SURVEY:STATus:DURation?
This query specifies the duration of the survey in progress or the last survey.
3.3.26 GPS:SURVEY:STATUS?
This query displays the current status of the survey. The status of the survey is in one of the 3 states:
ACTIVE : a survey is in progress