Abstract: Various methods, apparatuses and/or articles of manufacture are provided which may, for example, be implemented to compute one or more inferences from signals generated by one or more inertial sensors or environmental sensors, detect an erroneous condition responsive to a comparison of the computed inference(s) with an initial position or a position fix, and, in response to the detection of the erroneous condition, affect at least one process at the mobile device that is used, at least in part, to obtain a position fix.

Abstract: A position fix of a mobile device is computed based, at least in part, on a plurality of data items. A metric that is indicative of a reliability of the position fix may be generated based, at least in part, on a number of independent ones of the data items and/or an indication of reliability of at least one of the data items. In at least one implementation, the plurality of data items may include SPS satellite signals and/or pseudoranges and an externally obtained position.

Abstract: Various methods, apparatuses and/or articles of manufacture are provided which may, for example, be implemented to compute one or more inferences from signals generated by one or more inertial sensors or environmental sensors, detect an erroneous condition responsive to a comparison of the computed inference(s) with an initial position or a position fix, and, in response to the detection of the erroneous condition, affect at least one process at the mobile device that is used, at least in part, to obtain a position fix.

Abstract: A position fix of a mobile device is computed based, at least in part, on a plurality of data items. A metric that is indicative of a reliability of the position fix may be generated based, at least in part, on a number of independent ones of the data items and/or an indication of reliability of at least one of the data items. In at least one implementation, the plurality of data items may include SPS satellite signals and/or pseudoranges and an externally obtained position.

Abstract: A roving extended range high sensitivity satellite positioning system receiver provides position fixes in adverse signal conditions as low as minus 150 dbm and with as few as three satellites by measuring the bit phase of the navData message and the codephase, and finding a simultaneous solution. Previous position fixes that were obtained in the vicinity by earlier rovers are deposited in an indexed database for consultation. A cellular phone system can be used to simply communicate the current identity codes and their database entries.

Abstract: A cellphone system comprises a GPS reference station located with a telephone cell site. Such GPS reference station tracks the GPS satellites visible to its local area and estimates the Doppler for each such GPS satellite. The system also includes mobile GPS receivers and cellphones that move around and through the operational area of the cell site. It is assumed that the satellite Dopplers seen by the GPS reference station will have insubstantial differences with the true Dopplers observed by other GPS receivers operating within the cell site's service area. The Doppler estimates are thus routinely communicated over a wireless telephone channel to the mobile GPS receivers and cellphones that register locally. Such mobile GPS receivers then can confidently adopt the surrogate Doppler estimates as a center starting point for their initialization frequency searches. The time required for such mobile GPS receivers and cellphones to initialize and provide a first fix is thereby substantially reduced.

Abstract: A roving extended range high sensitivity satellite positioning system receiver provides position fixes in adverse signal conditions as low as minus 150 dbm and with as few as three satellites by measuring the bit phase of the navData message and the codephase, and finding a simultaneous solution. Previous position fixes that were obtained in the vicinity by earlier rovers are deposited in an indexed database for consultation. A cellular phone system can be used to communicate the vicinity ID's and their database entries.

Abstract: A cellphone system comprises a GPS reference station located with a telephone cell site. Such GPS reference station tracks the GPS satellites visible to its local area and estimates the Doppler for each such GPS satellite. The system also includes mobile GPS receivers and cellphones that move around and through the operational area of the cell site. It is assumed that the satellite Dopplers seen by the GPS reference station will have insubstantial differences with the true Dopplers observed by other GPS receivers operating within the cell site's service area. The Doppler estimates are thus routinely communicated over a wireless telephone channel to the mobile GPS receivers and cellphones that register locally. Such mobile GPS receivers then can confidently adopt the surrogate Doppler estimates as a center starting point for their initialization frequency searches. The time required for such mobile GPS receivers and cellphones to initialize and provide a first fix is thereby substantially reduced.