Precision farming is a form of multidisciplinary and technologically advanced agriculture, which recourses to machines equipped with "intelligent systems," able to dose the productive factors (fertilizers, pesticides, etc.) according to the real needs of the homogeneous areas constituent to the plot (Verhagen and Bouma, Modeling soil variability. In: Pierce FJ, Sadler EJ (eds) The state of site specific management for agriculture. ASA Publications, 1997).Experimental trials have been conducted in order to compare two satelliteguidance devices and two correction systems of the GPS signal: the EZ-Steer/ RTK and Autopilot/EGNOS. The machines used in the tests were the tractor New Holland T7060, the rotary harrow Alpego DG-400, and the burier Forigo DG-45, to determine which of the two systems ensured the best quality of work. The results obtained showed that the EZ-Steer/RTK system guaranteed a lower stability of the theoretical trajectory than the Autopilot/EGNOS system, above 1.69 %. From the elaboration of data of the two guidance systems behavior to manage the only width of transposition, it is observed that the EZ-Steer/RTK system is able to guarantee a better hold of the line compared to the Autopilot/EGNOS system, which provides a mistake of 176 cm on the total width of transposition and 2 cm on the mean value. In the matter of the normalized transposition surfaces, the Autopilot/EGNOS system ensures a better work quality.

The research has been conducted using two different satellite-guidance devices and two different correction systems of the GPS signal: the EZ-Steer/RTK and Autopilot/EGNOS. The machines used in the tests were the tractor New Holland T7060, the rotary harrow Alpego DG-400 and the burier Forigo DG-45, in order to determine which of the two systems ensured the best quality of work. On the basis of the results obtained it is clear that the EZ-Steer/RTK system, guarantees a lower stability of the theoretical trajectory compared to the Autopilot/EGNOS system, above 1,77%. From the elaboration of data of the two guidance systems behavior to manage the only width of transposition, it is observed that the EZ-Steer/RTK system is able to guarantee a better hold of the line compared to the Autopilot/EGNOS system, which provides a mistake of 164 cm on the total width of transposition and 2 cm on the mean value. In the matter of the normalized transposition surfaces, the Autopilot/EGNOS system ensures a better work quality.