10: Applications and Hints
GPS/GLONASS Receiver Module A5100-A User Guide
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10.7 Extended Ephemeris
The receiver is capable of supporting two versions of using Extended Ephemeris (EE)
data. The first one is the version, where the EE data are calculated on a server, are
transmitted to device incorporating the receiver, and are then loaded into the receiver.
These data can be valid for up to seven days.
The second version is the internal extrapolation of available “natural” Ephemeris data.
This is done automatically and no external support is required. The internally calcu-
lated EE data are valid for up to 3 days.
The receiver firmware will define which set of EE data to use or will neglect those in
case “natural” data are available. Both versions of EE data will help to further lower
power consumption in SiRFaware
TM
mode.