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Assisted GPS, A-GPS, AGPS

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SiRF A-GPS Chip

SiRF A-GPS chip

SiRF
Definition:

Assisted GPS, also known as A-GPS or AGPS, enhances the performance of standard GPS in devices connected to the cellular network. A-GPS improves the location performance of cell phones (and other connected devices) in two ways:

-By helping obtain a faster "time to first fix" (TTFF). A-GPS acquires and stores information about the location of satellites via the cellular network (see almanac) so the information does not need to be downloaded via satellite.

-By helping position a phone or mobile device when GPS signals are weak or not available. GPS satellite signals may be impeded by tall buildings, and do not penetrate building interiors well. A-GPS uses proximity to cellular towers to calculate position when GPS signals are not available.

Also Known As: A-GPS

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