Systems and methods for improving GNSS-based navigation

A system for global navigation satellite system (GNSS)-based navigation, the system comprising:

• at least one aircraft;
• and
• a computer system comprising one or more processors, wherein the one or processors are configured to:
• retrieve, from one or more databases:
• terrain data for a geographical region comprising, for each of a plurality of lateral positions in the geographic region, elevation values associated with a height of the terrain at the lateral position, and
• satellite orbit data for a GNSS comprising a plurality of satellites,
• for each time step of a plurality of time steps in a time period and for each lateral position of the plurality of lateral positions in the geographic region:
• determine, for each satellite of the plurality of satellites in the GNSS, a minimum height at which the satellite is visible from the lateral position at the time step,
• determine one or more unique combinations of satellites visible from the lateral position at the time step based on the minimum heights at which each satellite is visible from the lateral position, and
• generate, for each of the one or more unique combinations of satellites, one or more error objects indicating GNSS performance quality corresponding to the unique combination of satellites;
• determine GNSS performance quality information based on the one or more unique combinations of satellites and the respective one or more error objects;
• and
• operate the at least one aircraft based on the GNSS performance quality information.