Browsing by Subject "Egnos"

Need for higher productivity motivates and forces farmers to adapt new technological solutions. Global Navigation Satellite Systems (GNSS) have enabled several solutions to increase efficiency specially in field operations in terms of assisted or automatic steering, yield monitoring and precision farming. Accuracy of raw GNSS-data is poor and not suitable for any field operation. Methods to minimize error caused by different sources are in conclusive role to adapt positioning solutions to agriculture and to field operations. Aim of this study was to compare different GNSS correction methods by means of static and dynamic measurements. Results of the measurements occurred that high precision is achievable. Ground Based Augmentation Systems (GBAS) were more precise (RTK base station, AgriVRS and Centerpoint RTX) than Space Based Augmentation Systems (SBAS) (Omnistar G2 and Egnos). RMS values in 8 hour static measurements were between 0.004 and 0.406 m. Autonomic positioning RMS value was 1.014 m. In dynamic measurements scale was from 1.610 m to 0.015 m. Correction methods performed better in relative positioning than in repeating same position in subsequent days. Automatic steering is possible with every correction method. When using paid license corrections accuracy rises. Accuracy should be chosen by need of the field work, for example seeding needs higher accuracy than broadcasting of fertilizer. Due to Northern location of Finland SBAS are not available everywhere. Correction sent from satellite can be blocked for example by tree line. Also radio signal is hard to utilise in data transfer due to scattered field structure. Finland has excellent cellular network. Corrections loaded via cellular to receiver were available in test sites most practically.