Patent ID: 7486231
Filing Date: 2009-02-03
Classification: G01S

Abstract:
1. A device comprising: a first circuit arranged to receive at least one first signal and arranged to output first timing information dependent on said first signal; a second circuit arranged to receive at least one a second signal and arranged to output second timing information dependent on said second signal; and a third circuit arranged to determine timing information of said device, said third circuit arranged to receive at least one of said first and second timing information, and further arranged to produce a third timing information dependent on at least one of said received first and second signals, wherein said third circuit is farther arranged to produce a location estimate dependent on said first and third timing information; wherein said third timing information is initially synchronised to said first timing information and maintained substantially synchronised to said at least one first signal using said second timing information; and wherein said third circuit further comprises a cellular reference clock and wherein said third timing information is further maintained substantially synchronized to said at least one first signal using said cellular reference clock.