Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
74 words
A method for determining a loss of accuracy of a positioning system within an Emergency Call System (ECS) installed in a movable vehicle, said method comprising the steps of: determining an accuracy of a position solution of said positioning system; comparing said determined accuracy against a threshold value; and generating a warning to indicate that said ECS is not operational when said determined accuracy exceeds said threshold value based upon said step of comparing.
Claim 2
Independent Claim
74 words
A method for determining a loss of accuracy of a positioning system within an Emergency Call System (ECS) installed in a movable vehicle, said method comprising the steps of: determining an accuracy of a position solution of said positioning system; comparing said determined accuracy against a threshold value; and generating a warning to indicate that said ECS is not operational when said determined accuracy exceeds said threshold value based upon said step of comparing.
Claim 3
Dependent Claim
18 words
The method of claim 1 wherein said step of determining an accuracy includes using Kalman filtering covariance information.
Claim 4
Dependent Claim
18 words
The method of claim 1 wherein said step of determining an accuracy includes using Least Squares covariance information.
Claim 5
Dependent Claim
19 words
The method of claim 1 wherein said step of determining an accuracy includes using Weighted Least Squares covariance information.
Claim 6
Dependent Claim
22 words
The method of claim 1 wherein said step of determining an accuracy of a position solution includes using a dead reckoning system.
Claim 7
Independent Claim
97 words
A method for determining the failure of a subsystem of a positioning system within an Emergency Call System (ECS) installed in a movable vehicle, said positioning system including a global positioning satellite (GPS) subsystem integrated with a dead reckoning (DR) subsystem, said method comprising the steps of: determining an inconsistency between position solutions of said DR and GPS positioning subsystems; isolating said inconsistency to either said GPS subsystem or said DR positioning subsystem; and providing an indication that said ECS is not operational when one of said positioning subsystems has failed when compared to a predetermined threshold.
Claim 8
Independent Claim
97 words
A method for determining the failure of a subsystem of a positioning system within an Emergency Call System (ECS) installed in a movable vehicle, said positioning system including a global positioning satellite (GPS) subsystem integrated with a dead reckoning (DR) subsystem, said method comprising the steps of: determining an inconsistency between position solutions of said DR and GPS positioning subsystems; isolating said inconsistency to either said GPS subsystem or said DR positioning subsystem; and providing an indication that said ECS is not operational when one of said positioning subsystems has failed when compared to a predetermined threshold.
Claim 9
Dependent Claim
30 words
The method of claim 6 wherein said step of determining includes using DR sensor calibration filters that uses GPS information to improve accuracy of DR sensors within said DR subsystem.
Claim 10
Dependent Claim
26 words
The method of claim 6 wherein said step of determining includes using a DR heading filter that combines DR heading information with GPS derived heading information.
Claim 11
Dependent Claim
26 words
The method of claim 6 wherein said step of determining includes using a DR position filter that combines DR position information with GPS derived position information.
Claim 12
Dependent Claim
33 words
The method of claim 6 wherein said step of providing an indication includes the step of generating a warning to a user of said ECS that one of said positioning subsystems has failed.
Claim 13
Dependent Claim
62 words
An Emergency Call System (ECS) for installation on a movable vehicle, comprising: a cellular telephone system; a positioning system for determining a location of said movable vehicle; at least one sensor for activating said ECS; means for determining an integrity of said positioning system and for providing a warning to a user when said positioning system has failed according to a threshold.
Claim 14
Dependent Claim
62 words
An Emergency Call System (ECS) for installation on a movable vehicle, comprising: a cellular telephone system; a positioning system for determining a location of said movable vehicle; at least one sensor for activating said ECS; means for determining an integrity of said positioning system and for providing a warning to a user when said positioning system has failed according to a threshold.
Claim 15
Dependent Claim
22 words
The ECS of claim 11 wherein said means for determining an integrity includes means for determining an accuracy of said positioning system.
Claim 16
Dependent Claim
22 words
The ECS of claim 11 wherein said positioning system includes a global positioning satellite (GPS) subsystem and a dead reckoning (DR) subsystem.
Claim 17
Dependent Claim
27 words
The ECS of claim 13 wherein said means for determining an integrity includes means determining an inconsistency between position solutions of said DR and GPS receiver subsystems.