Patent ID: 7010262
Filing Date: 2006-03-07
Classification: G01S,H04K

Abstract:
1. A method for circumventing jamming of receivers for a global positioning system (GPS), the method comprising the steps of: determining that a receiver is being jammed by a jamming signal not originating from the GPS; responsive to determining the jamming signal, transmitting a first signal from a portable unit including the receiver to a component of a second positioning system that is different from the GPS; and receiving from the second positioning system a second signal that includes data that indicates a position for the portable unit determined in the second positioning system based at least in part on the first signal; wherein said step of transmitting the first signal further comprises including first data in the first signal for authenticating the portable unit as an authorized user of the second positioning system; and wherein said step of transmitting the first signal further comprises transmitting the first signal in a narrow beam that impinges on the component of the second positioning system and that does not impinge on a source of the jamming signals.