Abstract: A method for satellite receiver autonomous integrity monitoring (RAIM) real time fault detection and exclusion implementation comprising the following steps: (1) continuously computing a horizontal protection level (HPL) and a vertical 32 protection level (VPL) associated with the effective configuration of real time measurement geometry; (2) if the HPL is less than or equal to the horizontal alert limit (HAL), and/or if the VPL is less than or equal to said vertical alert limit (VAL); declaring the RAIM detection function available; (3) continuously computing a horizontal exclusion level (HEL) and continuously computing a vertical exclusion level (VEL) associated with the effective configuration of real time measurement geometry; and (4) if the HEL is less than or equal to the HAL, and/or if the VEL is less than or equal to the VAL, declaring the RAIM fault exclusion function available.

Abstract: A method for improving a satellite receiver autonomous integrity monitoring (RAIM) availability and fault detection and exclusion (FDE) function by using an adaptive threshold logic. The method comprises the following steps: (A) pre-computing a database of thresholds; (B) selecting in real time from the database a plurality of thresholds corresponding to a set of available measurements; and (C) determining an optimum RAIM/FDE function corresponding to the set of available measurements by using the adaptive threshold logic that utilizes the plurality of thresholds corresponding to the set of available measurements. The set of available measurements is selected from the group consisting of: {a GPS measurement, a GLONASS measurement, a GALILEO measurement, a baro measurement, a clock measurement, and a pseudolite measurement}.

Abstract: A multi-stage process for detecting and excluding faulty measurements in a satellite positioning system receiver are described. Availability of fault detection is evaluated based on satellite geometry and satellite measurement quality. If fault detection is unavailable using only satellite measurements, an additional measurement is used, and fault detection availability is again evaluated. If fault detection is available, detection of a potential fault is performed. If a fault is detected, an exclusion/isolation process is activated. In that case, a fault exclusion operation is tested for availability. If fault exclusion is unavailable using only satellite measurements, an additional measurement is incorporated, and fault exclusion availability is again evaluated. If fault exclusion is available, an attempt is made to isolate and exclude the faulty measurement from a list of satellite measurements used for the navigation solution.

Abstract: The method of supplementing the satellite data by the satellite-calibrated baro data when the receiver autonomous integrity monitoring function (RAIM) is unavailable and when the horizontal protection level (HPL) does not satisfy the horizontal alert limit (HAL) requirement is disclosed. The baro data is adjusted to compensate for the lack of baro calibration in the position solution domain. The HPL is re-computed using the satellite-calibrated adjusted baro data. The re-computed HPL could satisfy the HAL requirement which would make the RAIM function available when it would be otherwise unavailable.

Abstract: The method of supplementing the satellite data by the satellite-calibrated baro data when the receiver autonomous integrity monitoring function (RAIM) is unavailable and when the horizontal protection level (HPL) does not satisfy the horizontal alert limit (HAL) requirement is disclosed. The baro data is calibrated with satellite data if maximum weighted vertical dilution of precision with one satellite removed at one time (max {SubWVDOP}) is less than a predetermined threshold (TSUB) and if a test statistic is less than a predetermined test statistic threshold (TST). The HPL is re-computed using the satellite-calibrated baro data. The re-computed HPL could satisfy the HAL requirement which would make the RAIM function available when it would be otherwise unavailable.