The minimum number of satellites for a reliable position is 5 and HDOP (deviation) should be 1.5 or lower.
To improve your GNSS acquisition, retention and accuracy, please try the following.
On the physical tracker:
- Make sure the antenna (label side of the tracker in case of an internal antenna) is:
- Facing up perpendicular to the sky.
- It is not tilted more than 45 degrees in any axis, with the top surface perpendicular to the sky.
- Installed as close to the windshield as possible.
- Without any metallic objects or wiring in between.
- You could acquire an external GNSS antenna to improve GNSS fix acquisition. Check compatibility here:
- If problems persist, try doing a deep reset:
- disconnect from power supply
- disconnect from internal battery (you can do this physically or via Advanced Configurator "Battery off" button).
- reconnect internal battery
- reconnect power supply
On the configuration:
- Make sure all three GNSS systems are enabled: GPS, GLONASS and GALILEO. This will increase satellite availability and thus fix and accuracy.
Filtering unreliable coordinates:
Without GPS fix:
If record header looks like the one below (all GNSS derived values are maxed out / error), it means the record was generated and sent without first acquiring a GNSS fix.
Coordinates will be:
While this does not usually happen, because the device will not send a record unless a valid GNSS fix has been previously acquired after first power on / reset, if Send data without GPS fix is checked, the device will nonetheless send the record with the faulty header.
To avoid receiving such records, simply uncheck the box:
With gps fix:
- Enable Navigation filtering
- Stationary (discards coordinates that do not meet accuracy criteria when vehicle is not moving).
- Active (discards coordinates that do not meet accuracy criteria when vehicle is moving).
(example below is the default, more information HERE)