Jackson Labs Mini-JLT GNSS, Руководство пользователя

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Mini-JLT GNSS™
User Manual
18 © 2017 Jackson Labs Technologies, Inc.
After the Offset is removed, we may have to adjust the gain of the axis sensor. For example if the
range of the X Axis output is -82 Degrees to +78 Degrees then the axis has both an offset of 2
degrees, and a gain error of 90/80 Degrees (a factor of 1.125).
Thus we need to add 2 Degrees offset, and a gain of 1.125. The calibration command would thus look
as follows:
GPS:GYRO:CAL 2, 0, 0, 1.125, 1, 1
All three axis need to be calibrated simultaneously as shown above for the X Axis.
GPS:GYRO:CAL? returns the setting of the calibration factors of the accelerometer system.
Due to the nature of the accelerometer chip, the Z axis will have the largest error and lowest
sensitivity of all three axis. The X, and Y axis will have the best resolution and highest sensitivity
when the unit is sitting level (horizontally).
3.3.14 GPS:DYNAMic:MODE
This command allows the user to select the dynamic motion model being applied to the Kalmann
filters in the GNSS receiver. This allows for larger amounts of filtering for lower velocity
applications, effectively reducing noise and multipath interference. Applications with high
acceleration can now be used with fast filter settings to allow for the most accurate GPS coordinates
to be provided in high-dynamic applications such as Jet aircraft. Doppler tracking is enabled in all
airborne modes, as Carrier Phase tracking is very difficult to achieve in high velocity applications.
The GNSS receiver will perform Carrier Phase tracking for non-airborne modes.
The command has the following syntax:
GPS:DYNAMic:MODE <int> [0,8]
Sending the following command to the Mini-JLT GNSS™ will select a stationary GNSS dynamic
model for example:
gps:dynam:mode 1
The following table lists all available modes:
Value Model Application
0 Portable Recommended as a default setting