Fault detection and exclusion for global position systems
AssigneeHoneywell International Inc.
InventorsKevin D. Vanderwerf, Mats Brenner
Life of this patent
Estimating the term…
Abstract
A global positioning system for use with a plurality of transmitting satellites is disclosed wherein a full position solution is obtained from a number N of satellite transmissions and a plurality of sub-solutions each based on a different number (N−1) of satellite transmissions are obtained to determine if a satellite is faulty. A plurality of sub-sub-solutions is then obtained based on a different combination of N−2 satellites with each combination containing the satellites of different sub-solutions and excluding one other satellite in addition. An examination of the sub-sub-solutions provides an indication of which one of the satellites is the failed satellite.
Claims33
In a system for determining the position of a vehicle from the transmissions of a plurality of transmitters, one of which could be faulty, wherein a full position solution for the vehicle is determined from a combination of N transmissions and a plurality of position sub-solutions is determined from combinations of the N transmissions, each position sub-solution being based on different combination of the N transmissions but each excluding a different one of the transmissions to determine if there is a faulty transmission, the improvement comprising:
- sub-sub-solution means for producing a plurality of sets of position sub-sub-solutions from the sub-solutions, wherein each set of position sub-sub-solutions corresponds to one of the sub-solutions and wherein each position sub-sub-solution in a set is based on the corresponding sub-solution wherein a different additional one of the transmissions is also excluded;
- and
- failure isolation means for analyzing the position sub-sub-solutions to determine which, if any, of the transmissions is faulty.
In a position determining system for a vehicle having receiving means for receiving signals from a plurality of transmitters, one of which may be faulty, and having a processor for determining a full position solution for the vehicle based on the plurality of signals and determining a plurality of position sub-solutions for the vehicle with each position sub-solution based on a respective subset of the plurality of signals, the improvement comprising:
- means producing a plurality of position sub-sub-solutions for the vehicle with each position sub-sub-solution based on a respective subset of the position sub-solutions;
- and
- failure isolation means for determining which, if any, of the transmitters is faulty from the plurality of position sub-sub-solutions.
The method of operating a position determining system, which includes a processor which receives transmission signals from a plurality of transmitters, one of which may be faulty, comprising the steps of:
- A. determining a full position solution from a plurality of transmissions signals;
- B. determining a plurality of position sub-solutions, each based on a subset of the plurality of transmission signals;
- C. determining a plurality of position sub-sub-solutions, each based on a subset of one of the position sub-solutions;
- and
- D. determining from the plurality of sub-sub-solution, which of the transmitters, if any, is faulty.
Dependencies are inferred from the claim text.