Lassen SQ, Справочное руководство

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Lassen SQ GPS Receiver 8 1
Trimble Standard Interface Protocol (TSIP) A
When using the 2-D mode, expect fixes with accuracies which are at
best as accurate as the supplied altitude. If a marine user enters sea-
level as the altitude, then small errors in the horizontal solution will
occur when the sea state is rough or there are high tidal variations.
However, these errors may be smaller than the altitude errors induced
by SA, so 2-D may be preferable for a marine user who does not want
to observe “unusual” altitudes.
A.14.2
Dynamics Code
The feature default is LAND mode, where the receiver assumes a
moderate dynamic environment. In this case, the satellite search and
re-acquisition routines are optimized for vehicle type environments. In
SEA mode, the search and re-acquisition routines assume a low
acceleration environment and reverts to user entered altitude in 2-D
auto. In AIR mode, the search and re-acquisition routines are
optimized for high acceleration conditions.
A.14.3
Elevation Mask
This is the minimum elevation angle for satellites to be used in a
solution output by the receiver. Satellites which are near the horizon
are typically more difficult to track due to signal attenuation, and are
also generally less accurate due to higher variability in the ionospheric
and tropospheric corruption of the signal. When there are no
obstructions, the receiver can generally track a satellite down to near
the horizon. However, when this mask is set too low, the receiver may
experience frequent constellation switching due to low elevation
satellites being obscured.