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satellite orbital data to achieve maximum acquisition
performance. If significant inaccuracy exists in the initial
data, or if the orbital data is obsolete, it may take from 5 to
15 minutes to achieve a navigation solution. The GPS 30/
30 SL AutoLocate
TM
feature is capable of automatically
determining a navigation solution without intervention from
the host system. However, acquisition performance can be
improved if the host system initializes the GPS 30/30 SL
following the occurrence of one or more of the following
events:
1) Transportation over distances further than 1500
kilometers
2) Failure of the internal memory battery without system
standby power
3) Stored date/time off by more than 30 minutes
See Section 4 for more information on initializing the GPS
30/30 SL.
2.3 NAVIGATION
After the acquisition process is complete, the
GPS 30/30
SL will begin sending valid navigation information over its
output channels. These data include:
1) Latitude/longitude/altitude
2) Velocity
3) Date/time
4) Error estimates
5) Satellite and receiver status
Normally the GPS 30/30 SL will select the optimal navigation
mode (2D or 3D) based on available satellites and geometry
considerations. The host system, at its option, may
command the GPS 30/30 SL to choose a specific mode of
navigation, such as 2D. The following modes are available:
Summary of Contents for TracPak GPS 30/30 SL
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