US 9,429,654 B2 · Enhancement of the integrity concept of a satellite navigation system

Abstract

A method for determining the integrity risk at an alert limit of a position solution determined with a satellite navigation system involves calculating a first integrity risk at the alert limit assuming that one satellite j of the satellites is faulty. A first position solution is determined with the signals from all of the satellites and a second position solution is determined with the signals from all of the satellites except for the signal received from the satellite j. A difference between the first and the second position solution is identified and subtracted from the alert limit to create a reduced alert limit. A second integrity risk at the reduced alert limit is calculated with the signals received from all satellites except the signal received from the satellite j. The integrity risk at the alert limit is determined using the minimum of the first and second integrity risks.

Claims14

Dependent claims

A method for determining an integrity risk at an alert limit of a position solution determined by processing signals received from satellites of a satellite navigation system, the method comprising:

calculating a first integrity risk at the alert limit assuming that one satellite of the satellites is faulty;
determining a first position solution is determined with signals received from all of the satellites;
determining a second position solution with signals received from all of the satellites except for a signal received from the assumed faulty satellite;
determining a difference between the first and the second position solution;
creating a reduced alert limit by subtracting the determined difference from the alert limit;
calculating a second integrity risk at the reduced alert limit with the signals received from all satellites except the signal received from the assumed faulty satellite;
determining the integrity risk at the alert limit using a lower of the first and second integrity risks;
and
outputting the determined integrity risk by one of a display unit, a data output interface and an audio output unit.

6 more elements

A computer program for determining an integrity risk at an alert limit of a position solution determined by processing signals received from satellites of a satellite navigation system, wherein the computer program is stored on a non-transitory computer-readable medium, which when executed by a computer causes the computer to:

calculate a first integrity risk at the alert limit assuming that one satellite of the satellites is faulty;
determine a first position solution is determined with signals received from all of the satellites;
determine a second position solution with signals received from all of the satellites except for a signal received from the assumed faulty satellite;
determine a difference between the first and the second position solution;
create a reduced alert limit by subtracting the determined difference from the alert limit;
calculate a second integrity risk at the reduced alert limit with the signals received from all satellites except the signal received from the assumed faulty satellite;
and
determine the integrity risk at the alert limit using a lower of the first and second integrity risks.

5 more elements

An apparatus configured to determine an integrity risk at an alert limit of a position solution determined by processing signals received from satellites of a satellite navigation system, the apparatus comprising:

a receiver configured to receive signals from the satellites;
and
a processor configured to
calculate a first integrity risk at the alert limit assuming that one satellite of the satellites is faulty;
determine a first position solution is determined with signals received from all of the satellites;
determine a second position solution with signals received from all of the satellites except for a signal received from the assumed faulty satellite;
determine a difference between the first and the second position solution;
create a reduced alert limit by subtracting the determined difference from the alert limit;
calculate a second integrity risk at the reduced alert limit with the signals received from all satellites except the signal received from the assumed faulty satellite;
determine the integrity risk at the alert limit using a lower of the first and second integrity risks;
and
output the determined integrity risk by one of a display unit, a data output interface and an audio output unit.

9 more elements

Dependencies are inferred from the claim text.

Enhancement of the integrity concept of a satellite navigation system

Life of this patent

Enhancement of the integrity concept of a satellite navigation system

Life of this patent

Abstract

Claims14