What causes poor position data?
The positional data channels lat, long and height are not only affected in the short term by local obstructions and reflections, but they are also affected by changes in the Ionosphere.
The slow changing nature of the Ionosphere causes the signals from the satellites to take slightly different times to arrive at the GPS antenna. As the time is critical to the triangulation calculation of 3D position, this causes a potential error degrading the accuracy of the absolute positional accuracy.
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