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Navigation
• Clock drift: Internal errors in clocks can affect time measurements.
- Atmospheric disturbances:
• Ionospheric: Signals from satellites can be delayed in the ionosphere,
especially during solar activity.
• Tropospheric: Changes in weather and air pressure can cause signal
interference.
- Multipath effects:
• Reflections: Signals reflected from buildings, terrain, or other
surfaces can create inaccurate measurements.
- Signal interference:
• Interference: Electronic noise from other sources can interfere with signals
• Shielding: Signal blocking from buildings, mountains, or forests can
reduce the receiver's ability to pick up signals.
- Geometric errors:
• Satellite constellation: If the available satellites are closely spaced, this
can affect the accuracy of the position determination.
9.10.2.4 Troubleshooting Methods
Understanding the potential error types and having effective troubleshooting
techniques can help users of GNSS systems achieve more reliable and accurate
navigation solutions.
Examples include:
- Check whether there are enough satellites in view and their position relative
to the receiver.
- Ensure that the GNSS receiver is properly calibrated and updated with the
latest software and map information.
- Use a GNSS analysis tool to monitor signal strength and quality to identify
problems.
- Use augmentation: Implement systems such as DGPS or SBAS to improve
accuracy and compensate for errors.
Flyveteori PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 894
