Receiver for a satellite based position location system

A method of performing synchronisation for a receiver operating in a global positioning system comprising a plurality of satellites transmitting ranging signals, said synchronising being performed with respect to said transmitted ranging signals and comprises the steps of transform coding said received signal so as to transform said received signal from time domain to frequency domain coefficients, dividing respective ones of said frequency domain coefficients by corresponding ones of transform coefficients of the expected transmitted signal associated with said satellite to provide corresponding transform value ratios, and processing said transform value ratios so as to provide corresponding scaled values that are indicative of the time delay of the signal travelling between the satellite and the receiver.

A receiver for a satellite based positioning system operable so as to synchronise with respect to a received signal transmitted from a satellite of said system, said synchronisation comprising transform coding means for transform coding said received signal so as to transform said received signal from time domain to frequency domain coefficients, dividing means for dividing respective ones of said frequency domain coefficients by corresponding ones of transform coefficients of the expected transmitted signal associated with said satellite to provide corresponding transform value ratios, and processing means for processing said transform value ratios so as to provide corresponding scaled values that are indicative of the time delay of the signal travelling between the satellite and the receiver.

A satellite based positioning system in which a plurality of satellites transmit ranging signals and a receiver receives the transmitted ranging signals and performs synchronisation with respect to said ranging signals, said synchronisation comprising transform coding means for transform coding said received signal so as to transform said received signal from time domain to frequency domain coefficients, dividing means for dividing respective ones of said frequency domain coefficients by corresponding ones of transform coefficients of the expected transmitted signal associated with said satellite to provide corresponding transform value ratios, and processing means for processing said transform value ratios so as to provide corresponding scaled values that are indicative of the time delay of the signal travelling between the satellite and the receiver.

A computer program on a carrier for synchronising a receiver operating in a global positioning system comprising a plurality of satellites transmitting ranging signals, said synchronising being performed with respect to said transmitted ranging signals and comprises transform coding means for transform coding said received signal so as to transform said received signal from time domain to frequency domain coefficients, dividing means for dividing respective ones of said frequency domain coefficients by corresponding ones of transform coefficients of the expected transmitted signal associated with said satellite to provide corresponding transform value ratios, and processing means for processing said transform value ratios so as to provide corresponding scaled values that are indicative of the time delay of the signal travelling between the satellite and the receiver.

A computer program product operable to synchronise a receiver operating in a global positioning system comprising a plurality of satellites transmitting ranging signals, said synchronising being performed with respect to said transmitted ranging signals and comprises transform coding means for transform coding said received signal so as to transform said received signal from time domain to frequency domain coefficients, dividing means for dividing respective ones of said frequency domain coefficients by corresponding ones of transform coefficients of the expected transmitted signal associated with said satellite to provide corresponding transform value ratios, and processing means for processing said transform value ratios so as to provide corresponding scaled values that are indicative of the time delay of the signal travelling between the satellite and the receiver.

A portable radio communication device including a transceiver for cellular communication and a receiver for a satellite based positioning system operable so as to synchronise with respect to a received signal transmitted from a satellite of said system, said synchronisation comprising transform coding means for transform coding said received signal so as to transform said received signal from time domain to frequency domain coefficients, dividing means for dividing respective ones of said frequency domain coefficients by corresponding ones of transform coefficients of the expected transmitted signal associated with said satellite to provide corresponding transform value ratios, and processing means for processing said transform value ratios so as to provide corresponding scaled values that are indicative of the time delay of the signal travelling between the satellite and the receiver.