Providing sufficient navigation integrity is one of the most critical elements in the development Local Area Augmentation System (LAAS) architecture and remains an unsolved key technical problem. For example, in LAAS, the navigation integrity is ensured through the computation of the aircraft position error bounds (i.e., Protection Levels, VPL/LPL) in which implicitly zero- mean, normally distributed fault-free error models are assumed. However, it is understood that true ranging error cannot easily be described in this way, especially in the presence of ground reflection multipath. Therefore, to ensure navigation integrity of LAAS, the true ranging error must be bounded with zero-mean normal distribution. In this regard, a major ranging error source, ground reflection multipath, is specifically targeted in this research and new theoretical approaches are defined to bound and account for its effects.
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