Satellite navigation systems primarily rely on which kind of technology for their operation?

Satellite navigation systems primarily rely on triangulation using satellite signals for their operation. This method involves measuring the time it takes for signals sent from multiple satellites to reach a receiver on the ground. By determining the distance from at least three satellites through these time measurements, the receiver can pinpoint its precise location in three-dimensional space.

This triangulation process is fundamental to the functioning of systems like GPS, where satellites broadcast signals that are used by the navigation device to calculate its position accurately. The use of multiple satellites enhances the accuracy and reliability of the location data, as it compensates for potential errors or discrepancies in signal reception from any single satellite.

The other options do not play a significant role in the primary functioning of satellite navigation systems. Infrared technology is more commonly used in applications such as thermal imaging and night vision rather than positioning. Digital processing of ground data, while important in many systems, does not directly relate to how satellite navigation determines location since it is reliant on space-based signals rather than solely on ground-based data. Visual tracking systems are more suited for applications like radar and cameras rather than satellite navigation, which relies on radio signals from space.