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4.2.13. Satellites window
To go to the
Satellites
window, select the
Satellites
item from the
Plots
menu.
The
Satellites
window shows graphic representation of the satellite positions in the sky (Figure
55).
Figure 55. “Satellites” window
Each concentric circle represents the elevation angle above the horizon. The outermost circle corre-
sponds to 0 degrees above the horizon. The center of the sky plot represents 90 degrees above the
horizon. The dotted circle shows the elevation mask angle. In the figure above, the mask angle
equals 5 degrees. The user can adjust the mask angle through the
Elevation MaskForm
win-
dow which appears immediately after pressing the
Elevation mask
button. Also, the user can
see four DOP characteristics, specifically:
•
GDOP – Geometric (3 position coordinates plus clock offset in the solution);
•
PDOP – Position (3 coordinates);
•
HDOP – Horizontal (2 horizontal coordinates);
•
VDOP – Vertical (height only).
A dynamically changing histogram shows the signal-to-noise ratio (C/N0) in the C/A channel. Each
vertical bar has a unique color and designates a satellite’s PRN (GPS and WAAS) or slot number
(GLONASS). Note that GPS/WAAS and GLONASS satellites are marked with G# and R#, respec-
tively. By selecting or clearing the checkbox for each SV, the user can specify which of the GPS,
GLONASS and WAAS satellites are enabled/disabled for position computation.
