Patent ID: 6615135
Filing Date: 2003-09-02
Classification: G01C,G01S

Abstract:
A method of rapidly associating a position of a mobile receiver (MR) with a navigable route accessible in a map database, the map database including information representing predetermined navigable routes, comprising:seeding a predictive filter with an initial value indicative of an erroneous current position value of the MR displaced a predetermined minimum distance from a known approximate position of the MR to establish an initial gain of the predictive filter; receiving a positional signal over m time periods and deriving position values of the MR over the m time periods using the received signal; deriving predicted position values of the MR over the m time periods by predictively filtering the position values with the predictive filter; and determining a probable position of the MR at an end of the m time periods using a current predicted position value, the probable position coinciding with a navigable route of where the MR is probably positioned at the end of the m time periods.