How does RAIM ensure the integrity of GPS signals?

RAIM, or Receiver Autonomous Integrity Monitoring, plays a crucial role in ensuring the integrity of GPS signals by utilizing redundant signals and statistical analysis. This system works by comparing the signals received from multiple GPS satellites. It assesses the accuracy of these signals and determines whether they are consistent with one another. If a signal from a satellite appears to be an outlier, RAIM will identify it as potentially unreliable based on the statistical analysis of the other received signals.

This method helps ensure that the data being used for navigation is both accurate and reliable. If there is sufficient redundancy in the satellite signals (usually requiring at least five satellites for effective monitoring), RAIM can provide an indication of whether the GPS signal is safe to use for navigation. This is vital for aviation safety, particularly in critical scenarios where precise positioning is essential.

While other options suggest methods like encrypted signals, satellite cross-checks, or continuous ground monitoring, they do not encapsulate the specific mechanism by which RAIM effectively maintains the integrity of GPS signals through redundancy and statistical verification.