AssistNow: Assisted GPS service

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GPS users expect instant position information. With standard GPS this is often not possible because at least four satellites must be identified, and their complete orbital position data, called Ephemeris, received. Under adverse signal conditions, data downloads from the satellites to the receiver can take minutes, hours or even fail altogether. Assisted GPS (A-GPS) accelerates calculation of position by delivering satellite data such as Ephemeris, Almanac, accurate time and satellite status to the GPS receiver via wireless networks or the Internet. This aiding data enables a GPS receiver to compute a position within seconds, even under poor signal conditions. u-blox’ AssistNow service is available in Online and Offline versions which can be used alone or in combination. AssistNow requires no additional hardware and generates virtually no CPU load. The system is very easy to integrate: Customers can install it and be operational within a day. AssistNow service is available free-of-charge on a best-effort basis, or with guaranteed availability based on customer-specific service level agreement. AssistNow Online: up-to-date satellite information is automatically downloaded on each device start-up to allow instantaneous calculation of your position (TTTF less than 1 second). Size of downloaded data: 1-3 KB. AssistNow Offline: up-to-date satellite information is downloaded once every 14 days. Ephemeris data plus u-blox’ differential correctional almanac data then provide fast and accurate positional calculation for up to 2 weeks without a network connection, and in near real-time (as low as 5 seconds). u-blox products compatible with AssistNow: All u-blox GPS receiver modules All u-blox GPS receiver chips For further information: Please contact u-blox sales office to obtain access to the AssistNow service