Glossary of terms

B
• base station
  A GNSS receiver which supplies differential corrections to receivers equipped with GNSS. Also called a base or reference station.
• Baud rate
  This is the speed of data transfer, measured in bits per second.
D
• Differential GPS
  A method that uses correction data from satellite services or fixed reference stations to increase GPS accuracy. The satellites or local reference stations send correction data to vehicles equipped with GNSS receivers.
E
• Easting/Northing
  The Easting and Northing values show the Universal Transverse Mercator (UTM) position and zone of the vehicle. They are expressed in meters. The grid numbers on the east-west (horizontal) axis are called the Eastings, and the grid numbers on the north-south (vertical) axis are the Northings.
• EGNOS
  (European Geostationary Navigation Overlay Service). This is a European SBAS developed to supplement GPS, GLONASS and Galileo systems by reporting on the reliability and accuracy of the signals.
• EMC
  Electromagnetic Compatibility is a study of the impact of electromagnetic interference. EMC aims to ensure that equipment items or systems will not interfere with each other or prevent correct operation as a result of their electromagnetic emissions.
F
• Fallback
  Satellites and correction sources require specific position accuracy when computing the position of the vehicle. If the system is not receiving enough data to compute the vehicle position with the necessary accuracy, the autosteer function will not be enabled. The fallback feature allows the system to bypass the position accuracy requirement so that auto steering can be engaged. This is useful in situations where a high degree of position accuracy is not required. This is useful in situations where a high degree of position accuracy is not required.
• Field
  Defined working area of the tractor.
• field boundary
  The edge of the field.
• Firmware
  A programme embedded in the hardware of a device.
G
• GDOP
  (Geometric Dilution of Precision) GDOP is a system used to measure the accuracy of GNSS satellite geometry.
• GLONASS
  Global Navigation Satellite System (Russian GNSS)
• GNSS
  Global Navigation Satellite System
• GPS
  Global Positioning System (US GNSS)
• guideline
  The virtual line between two way points in a field. The guideline is used as reference for further passes in the field (also known as wayline).
H
• HDOP
  (Horizontal Dilution of Precision) HDOP is a metric for quantifying the accuracy of the horizontal (latitude/longitude) position information received from the GNSS satellites.
• HRMS
  The HRMS (Horizontal Root Mean Squared) parameter calculates an average horizontal position from the source information from the satellites.
L
• Latitude
  The distance of a position north or south of the equator measured in degrees. One minute of latitude is equal to one nautical mile (1852 m). The equator has a latitude of zero.
• Longitude
  The distance of a position east or west from the prime meridian measured in degrees. The prime meridian runs through Greenwich, England, at a longitude of zero.
M
• mobile base station
  An easily movable base station that can independently determine its new position so that it can continue to interact with the DGPS system.
• Mounting bias
  Mounting bias refers to whether the receiver is exactly level, when installed.
• MSAS
  Multi-functional satellite augmentation system. This is a Japanese SBAS which supplements the GPS by reporting and improving on the reliability and accuracy of the GPS signals.
N
• NMEA
  (National Marine Electronics Association). This is a standard protocol used by electronic devices to receive and transmit data.
O
• OmniSTAR
  A commercial service that receives GPS signals from NAVSTAR, checks them for errors and then uploads the error correction data to the OmniSTAR satellites.
R
• Reference Station
  A GNSS receiver which supplies differential corrections to receivers equipped with GNSS. Also known as base station.
• RTK Network
  Association of base stations which transmit their position data to a server over an internet connection (NTRIP). The vehicles in the RTK network (rovers) also transmit their position to the server via mobile radio. The server uses the position data from the base stations and vehicles to calculate the correction data for each vehicle and transmits this data to the vehicle via mobile radio. This allows real time position determination with an accuracy of 1-2 cm.
S
• SBAS
  (Satellite-Based Augmentation System). This is a system which supports wide area or regional augmentation through the use of additional satellite broadcast messages. SBAS correction sources are commonly composed of multiple ground stations which take the measurements of one or more GNSS satellites, and the satellite signals and environmental factors that may impact the signal.
• SCR-40
  High precision GPS antenna with roll/pitch angle compensation.
• Shapefile
  A shapefile stores non-topological geometry and attribute information for spatial features in a data set. The geometry for a feature is stored as a shape comprising a set of vector coordinates with the format abcd.shp.
• SR-10
  Low precision GPS antenna for EGNOS system without roll/pitch angle compensation.
W
• WAAS
  (Wide Area Augmentation System). This US SBAS was developed by the US Federal Aviation Administration to serve as an air navigation aid by improving the accuracy and availability of the GPS signals.
• WAS
  Wheel angle sensor
• wayline
  The virtual line between two way points in a field. The wayline is used as reference for further passes in the field (also known as guideline).