For the automation of different agricultural tasks, an autonomous mobile field robot (BoniRob) has been developed within the scope of a research project of the companies AMAZONEN-Werke H. Dreyer GmbH & Co. KG, Robert Bosch GmbH and the University of Applied Sciences Osnabrück. It serves as a carrier platform for various devices, so-called BoniRob-Apps. In addition, a Penetrometer-App for the automated measurement of penetration resistance [MPa] has been developed at the University of Applied Sciences Osnabrück. Within the scope of this diploma thesis, the development of a software module for the GNSS-based navigation of BoniRob is described. Thereby, for the purpose of approaching predefined measuring points a waypoint navigation has been implemented. Automated penetration resistance measurements are executed and georeferenced at this measuring points. Network-RTK measurements were used for positioning. Planning and analysis of the measurement process was done using a GIS-Software. The Robot Operating System (ROS) was used as software-framework for the implementation of the navigation module. The implementation of a browser-based graphical user interface to control the navigation module was made with the Web Toolkit (Wt). Following aspects have to be considered for the purpose of navigation: Determination of the sequence of approaching the individual measuring points (VRP), planning an executable path for the robot platform to the next target point and azimuth determination using RTK-positioning while the robot is driving. Furthermore, the integration of additional sensors (odometer and IMU) has been tested. For the evaluation of the navigation module several field tests were performed at a trial farm of the University of Applied Sciences Osnabrück. Thereby, as part of field tests using the automatic navigation mode 35 measuring points in a 10 x 10 m grid could be approached with an accuracy of approx. 10 cm (mean distance of target point). However, to remedy the occurred problems during navigation, the coordination of path planning (motion primitives) and run commands needs to be improved. The performed penetration resistance measurements have been interpolated applying an OS Kriging Software and visualized using a GIS.