Patent ID: 10422872

Abstract:
Methods for radar altimeter integrity monitoring are provided. One method comprises obtaining one or more GNSS measurements, or one or more hybridized GNSS/INS measurements, in an earth-centered-earth-fixed (ECEF) coordinate frame for a vehicle; obtaining one or more altitude measurements from one or more radar altimeters; transforming the altitude measurements into the ECEF coordinate frame using a terrain map and a GNSS or hybridized GNSS/INS based position estimate with ensured integrity; determining a full solution estimate of position for the vehicle based on the transformed altitude measurements, and the GNSS or hybridized GNSS/INS measurements; determining one or more sub-solution estimates of position based on a subset of the transformed altitude measurements, and the GNSS or hybridized GNSS/INS measurements; comparing the full solution estimate with the sub-solution estimates using statistical analysis; and determining an altitude protection level based on a probability of hazardous misleading information and a probability of false detection.