Valid and invalid positions in GpsGate Server
In this article we want to address the most common questions about invalid positions and how they are handled in GpsGate Server.
What are invalid positions
A position is invalid when the tracker sends non-updated or unreliable position information. In other words, if a tracker sends data when it is not possible to determine its location, it will generate a message with an invalid position.
The most common factors that make a position invalid, among others, are these:
- The GPS device isn’t located under clear sky.
- The number of satellites at the current location are not enough to triangulate a position.
- The type and location of the GPS antenna (internal or external).
How invalid positions are displayed
If a device presents invalid positions, you will be able to see them in different ways on the interface:
In the vehicle panel, any device sending invalid positions will look like in the pending status.
Observing the Tracking Points
You can distinguish invalid positions because they are greyed out in comparison to the valid ones, or you can even add the column Valid to the list.
Analyzing the Terminal Window data
Another approach to verify if a position is invalid or not, is by inspecting in the Terminal.
- Invalid positions are not being taken into account when the tracks are drawn on the map. Only valid positions are represented as tracks when using Draw tracks option in the Tracking Points panel.
- Read more about diagnosing terminal data here.
Invalid positions and Event Rules
Invalid positions are not being ignored by Event Rules. Event Rules will evaluate the message if the device sending method is set in order. Read more here.
Invalid positions and Reporting
Invalid positions are considered in reports in general, however, information in reports that requires a valid position to be correct will ignore them.
(e.g: If distance is calculated using GPS positions, the invalid position will not be part of that calculation).
- Note: Addresses will not be looked up by the geocoder if the position for the address is invalid.