John Deere offers its own differential corrections through the StarFire™ network
John Deere is proud to be the only company in the precision agriculture market to offer its own differential corrections through the StarFire network. Developed in 1998, the StarFire network was the world’s first Global Satellite-Based Augmentation System (GSBAS) capable of decimeter real-time accuracy. It is true everyone uses the same raw satellite signals, but differential corrections are another story. Because John Deere owns its own network of reference stations and processing hubs, users do not have to rely on Wide Area Application Services (WAAS) or go to a third-party differential corrections service.  
StarFire reference stations, Inmarsat satellites

StarFire reference stations, Inmarsat satellites

Any guidance system today relies on satellites to generate a position. Satellite constellations such as GPS, GLONASS, or Galileo orbit the Earth in all conditions around the world, 24 hours a day. A position receiver receives ranging signals from the constellation of satellites it is compatible with based on the calculated location of each satellite. The raw satellite signal’s accuracy is several meters, which is not acceptable for precision agriculture applications. To achieve a higher level of accuracy, these satellite signals are improved through John Deere’s StarFire network.

The StarFire network is a major advancement from earlier ground-based augmentation systems because it considers the signal error sources for all of the satellites at the same time. Satellite orbit and clock corrections are calculated from a global tracking network of dual-frequency receivers. These corrections are transmitted via six Inmarsat satellite links directly to StarFire receivers, resulting in minimal data latency and the ability to operate worldwide with redundant coverage.

The position receivers that utilize the network include:
  • Original StarFire
  • StarFire iTC
  • StarFire 3000, the latest receiver from John Deere

Each one of these receivers is a dual-frequency satellite receiver that measures the ionospheric delay for each satellite.

With the StarFire network, performance is not a function of the distance from a reference station, allowing producers the freedom to use StarFire SF1 and SF2 around the world without a base station. Orbit and clock corrections from the processing centers in Moline, Illinois, and Torrance, California, are distributed by dedicated circuits around the world with multiple communication backups to the Inmarsat satellite uplink stations. Utilizing multiple data links, processing hubs, and dual-frequency receivers ensures reliable positioning.

The fully automated, continuously self-monitoring system is overseen around the clock by StarFire network operators to ensure maximum reliability. The StarFire network continues to receive upgrades and other enhancements to improve the performance of StarFire position receivers.
 
Last Updated : 23-Jul-2013