Patent ID: 7190307

Claim:
An apparatus, comprising: a receiver receiving a signal having a plurality of pseudo noise codes, where each of the pseudo noise codes of the plurality of pseudo noise codes originates from a GPS transmitter, where a plurality of chips make up each pseudo noise code in the plurality of pseudo noise and the plurality of chips is offset between 511 chips before a pseudo noise code boundary and 512 chips after the pseudo noise code boundary; a local clock with an error of less than 0.5 ms relative to a GPS time; and a decoder connected to the receiver and the local clock that is synchronized to the signal, identifies four pseudo range equations for at least four GPS transmitters from the plurality of GPS transmitters, and determines a location of the receiver by simultaneously solving the four pseudo range equations that use a determined error (C j −Ĉ j ) in the receivers time estimate with a chip C j that is offset from an expected chip Ĉ j .