Positioning errors can be mitigated in a number of ways:
- Wait for a few more epochs (seconds) to see how the accuracy converges before reading in the position value. Normally it should not take more than 3-4 seconds after the first fix for the positioning value to converge to the expected value and within any error threshold you may have set.
- Use the average of the first 3 or 4 epochs instead of just the first epoch.
- Because altitude (and overall quality of the Fix) degrades with the age of data used it is recommended to stop checking the altitude for older data and check other parameters instead.
Note: Altitude always has the worst performance due to satellite constellation geometry.
This solution originated from the article: Why isn't the positioning of my GNSS receivers with AssistNow always accurate?
To review the latest global ionospheric activity please see: Where can I review global ionospheric activity?