Figure 22: Gps Satellite Status Screen - NorthStar 961 Install Manual

SECTION TWO - Installation
Page 32
Once the unit has been turned on and has acquired satellite data, you can
check the quality of the GPS signals by viewing the various satellites' SNR
(Signal-to-Noise Ratio) readings.
GPS receiver status summary
To display information about the GPS satellites, press the
display the SERVICE MENU screen, then press the
961/962 displays the GPS SATELLITE STATUS screen, showing the status
of the GPS receiver. For 961XD and 962XD systems, this screen also
displays the status of the DGPS receiver.
The GPS SATELLITE STATUS screen shows the received Signal-to-Noise
Ratio (SNR) for up to 12 satellites, and a map indicating where the
satellites are now located in the sky. Satellites are identified by their
pseudorange noise number (PRN), two digits that are assigned by the U.S.
government. The center of the satellite map represents the center of the
sky, and the outer ring is the horizon. The view is looking down from
above, with East to your right and West to your left.
Also displayed on this screen is the following GPS data:
•
accuracy
•
horizontal dilution of precision (HDOP)
Accuracy is the expected estimated accuracy of the GPS system at the
current time. Your position readings should be more accurate than this
estimate 95 percent of the time.
HDOP is a technical measure of the fix-taking quality of the satellite
pattern in the sky. HDOP depends on the number of operational satellites
in view and their current location. HDOP is calculated from the satellites'

Figure 22: GPS satellite status screen

961/962 INSTALLATION MANUAL Revision A
key to
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