Using Dgps Or Waas - NorthStar 6000i Quickstart Manual And Reference Manual

sented by circles; WAAS satellites are
represented by hexagons.

Using DGPS or WAAS

When using the 6000i with standard
WAAS or an external radiobeacon DGPS
receiver, you'll usually see position
measurements accurate to about one to
three meters, speed measurements
accurate to about 0.1 knot, and COG
measurements accurate to about 0.5
degree. WAAS or DGPS corrections remove
most of the errors caused by atmospheric
variations.
When the WAAS or DGPS indicator is
displayed at the right edge of the screen,
the 6000i is using this higher level of accu-
Reference section 2 — Position coordinates
46

Using DGPS or WAAS

The center of the satellite map represents
the center of the sky, and the outermost
ring is the horizon. The view is looking
down from above, with east to your right
and west to your left.
HDOP (Horizontal Dilution of Precision) is
a technical measure of the quality of your
position fix. It is calculated from the satel-
lites' current positions. You'll usually see
an invalid HDOP value displayed immedi-
ately after the 6000i is turned on, before
it's ready to navigate. HDOP can range
from an ideal value of slightly less than
one, up to poor values of 10 or more. Any
value less than two indicates an excellent
Satellite status screen
satellite configuration.
racy. When you require this additional
accuracy, be sure to check often to verify
that either the WAAS or DGPS indicator is
present.
For most applications, the built-in WAAS
receiver automatically supplies highly
accurate navigation data. DGPS correc-
tions are available only from a user-sup-
plied external DGPS receiver using the
SC-104 data format. No DGPS signal sta-
tus is displayed.
Northstar 6000i