Hotstart - SimCom SIM548C HD V1.01 Hardware Design

SIM548C Hardware Design

4.9.3 Hotstart

Hotstart is performed whenever the receiver still has access to valid ephemeris data and exact time.
This procedure starts if the receiver has been shut off for less than 2 hours and the GPS RTC has
been running during that time. Furthermore, during the previous session, the receiver must have
been navigating (to allow it to decode and store ephemeris data). In Hotstart, the receiver can
announce in advance the currently visible satellites, and is therefore able to quickly obtain and
track the signal. Due to the fact that ephemeris is already known, there is no need to wait for the
ephemeris broadcast to complete.
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SIM548C_HD_V1.01 09.05.2008