CSI Wireless DGPS MAX, Reference Manual

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DGPS MAX Reference Manual
8
available if the signal passes through the ionospheric map provided by
WAAS, which covers the majority of North America.
To improve upon the ionospheric map provided by WAAS, the DGPS
MAX extrapolates information from the broadcast ionospheric coverage
map, extending its effective coverage. This allows the DGPS MAX to be
used successfully in regions that competitive products may not. This is
especially important in Canada for regions north of approximately 54
°
N
latitude and east of 110
°
W longitude. Please note that the process of
estimating ionospheric corrections beyond the WAAS broadcast map
would not be as good as having an extended WAAS map in the first place.
This difference may lead to minor accuracy degradation.
Figures 1-1 and 1-2 depict the broadcast WAAS ionospheric map extent
and the CSI Wireless extrapolated version, respectively. As can be seen
from Figure 1-2, the coverage compared to Figure 1-1 extends further in all
directions, enhancing usable coverage.
Figure 1-1 Broadcast WAAS Ionospheric Correction Map