Trimble Inc. 66400 Manual De Usuario
Juno Series User Guide
65
Using the GPS receiver
5
Planning a data collection session
To maximize productivity, plan GPS data collection
around the times of the day when satellite geometry is
best. The GPS Controller software includes a Plan
section with an animated skyplot and DOP (satellite
geometry) graph for your position for the next 12 hours.
around the times of the day when satellite geometry is
best. The GPS Controller software includes a Plan
section with an animated skyplot and DOP (satellite
geometry) graph for your position for the next 12 hours.
In the Plan section, you can check the planning skyplot
as you play a session, then use the timeline to zoom in
on times when geometry is poor.
as you play a session, then use the timeline to zoom in
on times when geometry is poor.
Note –
If you have other Trimble GPS field software
installed, use the planning feature in that application
instead of the GPS Controller software.
instead of the GPS Controller software.
Differential GPS explained
Use differential GPS to correct errors in your collected data. Differential GPS (DGPS)
requires one or more additional receivers, called base stations or reference stations,
which are located at known points. Data collected at the base stations is used to
determine GPS measurement errors and compute corrections to these errors. An
unlimited number of mobile GPS receivers, called rovers, collect GPS data at unknown
locations within the vicinity of the base station. Errors common at both the base
station and the rover receiver are corrected with DGPS either in real time or during
postprocessing.
requires one or more additional receivers, called base stations or reference stations,
which are located at known points. Data collected at the base stations is used to
determine GPS measurement errors and compute corrections to these errors. An
unlimited number of mobile GPS receivers, called rovers, collect GPS data at unknown
locations within the vicinity of the base station. Errors common at both the base
station and the rover receiver are corrected with DGPS either in real time or during
postprocessing.
Real-time DGPS
In real-time DGPS, the base station calculates and broadcasts the error for each
satellite as each measurement is received, enabling you to apply corrections while in
the field and collect accurate GPS data. DGPS corrections are available from a variety
of public and commercial sources. They can be generated and broadcast in real-time
by privately or self-owned GPS base stations, or by a wide range of government
agencies.
satellite as each measurement is received, enabling you to apply corrections while in
the field and collect accurate GPS data. DGPS corrections are available from a variety
of public and commercial sources. They can be generated and broadcast in real-time
by privately or self-owned GPS base stations, or by a wide range of government
agencies.
Real-time DGPS corrections can be used on the Juno Series handheld from Satellite
Based Augmentation Systems (SBAS) such as WAAS in the US and EGNOS in Europe.
SBAS uses multiple base stations to calculate the DGPS corrections that are then
delivered to the user from a Geostationary satellite.
Based Augmentation Systems (SBAS) such as WAAS in the US and EGNOS in Europe.
SBAS uses multiple base stations to calculate the DGPS corrections that are then
delivered to the user from a Geostationary satellite.
Factors that affect real-time DGPS accuracy include how often the corrections are
updated, how far you are from the base station, and whether the coordinate system
used by the correction source matches the coordinate system used by the GPS receiver.
updated, how far you are from the base station, and whether the coordinate system
used by the correction source matches the coordinate system used by the GPS receiver.