Spraying Systems TeeJet Matrix 908, Руководство пользователя

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Matrix 908 Field Computer
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GNSS (Global Navigation Satellite System):
A general term that refers to a multiple satellite navigation system used by a receiver to compute its position. Examples of these systems
include: GPS developed by the United States and GLONASS by Russia. Additional systems in development include Galileo by the European
Union and Compass by China. New generation GNSS receivers are being designed to utilise multiple GNSS signals (such as GPS and
GLONASS). Depending on constellation and desired accuracy levels, system performance may be improved by having access to a greater
number of satellites.
GPS (Global Positioning System):
The name of the satellite-navigation network maintained by the U.S. Department of Defense. It is composed of approximately 30 satellites
which continuously orbit the earth. The term is also used to refer to any device that depends on navigation satellites for functionality.
NTRIP (Networked Transportation of RTCM via Internet Protocol):
An internet-based application that makes the RTCM correction data from the CORS stations available to anyone with an internet connection
and the appropriate log-on credentials to the NTRIP server. Typically uses a cellular link to get to the internet and the NTRIP server.
Positional Drift
The constant change in the GNSS position calculation primarily caused by atmospheric and ionospheric changes, poor satellite geometry
(possibly caused by obstructions such as buildings and trees, satellite clock errors and satellite constellation changes. For sub-decimetre
accuracy dual frequency receivers using either PPP or RTK solutions are recommended.
RTK (Real time kinematic):
Currently the most accurate GPS correction system available that uses a land-based reference station located in relatively close proximity
to the GPS receiver. RTK can provide one-inch, also known as centimetre, pass-to-pass accuracy and also provides year-to-year position
stability. RTK users can have their own base stations, subscribe to RTK Networks or use CORS.
SBAS (Satellite Based Augmentation System):
A general term that refers to any satellite-based differential correction system. Examples of SBAS include: WAAS in the United States,
EGNOS in Europe and MSAS in Japan. Additional SBAS covering other regions of the world will likely be coming online in the future.
WAAS (Wide-Area Augmentation System):
A satellite correction service developed by the Federal Aviation Administration (FAA). It is free to use and provides coverage across the U.S.
along with parts of Canada and Mexico. WAAS delivers pass-to-pass accuracies of 15-25 cm; however, year-to-year accuracy will be in the
range of +/-1 m.