This activity defines and validates advanced techniques for the monitoring of nominal and non-nominal signal distortions.

The activity is analyzing, very thoroughly, potential advanced monitors that rely on prior assumptions on the characteristics of the non-nominal distortion (amongst these, a "Chip-Domain-Observable (CDO)" monitor, and a “Beta-Metrics (BM)” monitor), for which a comprehensive evaluation of the attainable performance (based on early field data sets blended with mathematical analyses) is being performed. The advanced techniques defined within this activity indicate a very visible performance enhancement with respect to known legacy methods, without increasing substantially receiver hardware complexity.

Furthermore a visible effort is been performed on the definition of the mathematical/engineering generalized-methods for the monitoring of potential GNSS signal-in-space distortions (i.e. methods not requiring of strong prior assumptions on the characteristics of the distortion); in particular on methods for - constructing a finite representation of the signal-in-space distortion, on methods for detecting (from the above said finite representation) the presence of a non-nominal distortion, and ultimately on methods  for bounding the worst-case range error which could affect the user.

The Techniques Review KO took place on late November 2018, and is in its close-out process.