Evaluating Integrity and Continuity Over Time in Advanced RAIM

The Service Evolutions Sub-Group (SESG) of Working Group C, the joint technical committee formed from U.S and E. U public bodies for the purpose of promoting GPS-Galileo applications, has spent the past years working on a number of topics relating to Advanced RAIM development and its early stages of standardization. This paper addresses the mapping of integrity and continuity requirements from the operational (i.e. per hour) to the algorithmic (per sample). It provides a method to rigorously account for the impact on integrity risk of multiple exposures to hazardously misleading events over time, and for the impact on false alert probability of multiple detection tests over time. This analysis leads to the estimation and bounding of the “number of effectively independent samples”, or more concisely the “number of effective samples (NES), for integrity and continuity within their respective exposure windows.