Fixed Subset Selection to Reduce Advanced RAIM Complexity
Juan Blanch, Todd Walter and Per Enge, Stanford University
Location: Grand Ballroom F
Date/Time: Tuesday, Jan. 30, 2:35 p.m.
Advanced RAIM has the potential of achieving global coverage of vertical guidance, even with large probabilities of satellite fault. To achieve this performance, airborne receivers will need to take into account a large number of fault modes resulting from the combination of single satellite and single constellation faults. Baseline implementations of ARAIM require the computation of a subset position solution (or at least the associated error covariance) per fault mode, which can result in a large computational burden. Consolidating the fault modes can reduce the list of subsets very significantly. This paper proposes to use a fixed set of subsets for a dual constellation configuration. This approach has two advantages: it simplifies the algorithm (the list of subsets is no longer dynamic), and it reduces the computational load. For a baseline GPS – Galileo configuration, the number of subsets is reduced from several thousands to less than seventy with a minimal impact on availability.