Using Trimble's Planning Software

For GPS Condition Predictions

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See also    Ephemeris Data (downloading)

                Quick Plan software information and examples (part of Trimble's Pathfinder Office software suite)

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The current and predicted GPS Satellite locations and timing are contained in what is known as the ephemeris data. This data can be used to predict GPS satellite constellations in the future and thus can be used for scheduling so as to maximize the quality of data collected.

Trimble's Planning software uses downloaded ephemeris data for satellite predictions. The downloaded ephemeris almanac (almanac.alm) is typically stored in the C:\Program Files\Common Files\Trimble\Planning folder). By knowing in advance which times of day will have better or worse satellite configuration conditions you can schedule your data collection so as to maximize your positional accuracy. For more information see the Planning help files.

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Below are examples of predictive graphs generated with the Planning software

To use Planning software you first need to establish your Station location (File / Station)
For Bellingham, click on the City... button and browse for Bellingham, WA
You can also change the Date and or time Duration to display

Having established your Station, you can display various satellite prediction graphs.

From the Graphs menu choose Number of Satellites

Graphs / Number of Satellites: shows the number of satellites available throughout the day for the chosen date and location (more satellites is better).

Graphs / DOP / DOP - Position: Shows the PDOP (Positional Dilution of Precision) for the given date and location (a lower DOP is better since you don't want much dilution of preision)

Graphs / Visible Satellites / GPS: shows which satellites will be available for the given date and location.

Graphs / Elevation: shows the elevation for the different satellites for the given date and location.

Graphs / Skyplot: shows the paths across the sky for the different satellites for the given date and location.

Graphs / World Projection: shows the flight paths of the various satellites throughout the course of the day

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