Patent ID: 9046591
Filing Date: 2015-06-02
Classification: G01C,G01S

Abstract:
1. A method of directing a user from an initial location to a destination location in an area containing a plurality of radio signals of opportunity and without knowing coordinates for transmitters of said plurality of radio signals of opportunity, said method comprising the steps of: obtaining a first set of location-dependent radio signal parameters for said destination location from said plurality of radio signals of opportunity; measuring subsequent sets of location-dependent radio signal parameters for a plurality of points away from said initial location; comparing said subsequent sets of location-dependent radio signal parameters with said first set of location-dependent radio signal parameters to produce a location-dependent radio parameter matching error; generating a directional command for a move if said radio signal parameter matching error exceeds a pre-determined threshold; and updating said directional command until said radio signal parameter matching error falls within a pre-determined threshold.