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This paper presents the concept of precise navigation based on SBAS technology and CORS stations. In a kinematic test, three rover Global Positioning System (GPS) receivers, properly spaced relatively to each other, were used in order to estimate reliable and redundant GPS/EGNOS positions. Next, the Kalman filter was employed to give the final solution. It was proven that EGNOS positioning allows to obtain an accuracy in the range of about 0.5–1.5 m. The proposed solution involving the use of three mobile receivers and Kalman filtering allowed to reduce the 3D error to a level below 0.3 m. Such an accuracy was achieved using only GPS L1 code observations and EGNOS corrections. Additionally, a reliable monitoring of quality of GPS/EGNOS positioning in the test area based on CORS stations was presented.

The Global Navigation Satellite System (GNSS) is increasinglyused in navigation and positioning in land, water and air applications.Although they are very useful and willingly employedin everyday live and commercial products, it must be stressedthat GNSS alone does not always provide adequate performance,particularly in demanding aeronautical applicationswhere high level of integrity is required. Integrity and accuracyof positioning are the key parameters in air navigation.The paper presents research on current values of GNSS accuracyand integrity in north-eastern Poland, the region whichuntil 2014 was out of official coverage of European GeostationaryNavigation Overlay Service (EGNOS) Open Service (OS).The integrity and accuracy of positioning of static point andflying aircraft was examined in order to check present usabilityof different GNSS techniques which can be deployed for enroute,approach and landing phase of a flight. Since the integritylevels in aviation are strictly dependent on the phase offlight and landing of an aircraft, the analyses were performedin two computational modes: positioning using GPS/EGNOSdata and using autonomous GPS. Both modes were calculatedin en-route variant and because with the use of EGNOS it ispossible to perform approach, GPS/EGNOS mode was alsoanalyzed in Precision Approach (PA) variant. Overall assessmentof the accuracy and integrity of positioning in the studiedvariants is at the satisfactory level, not exceeding the levelsdefined by official aviation regulations.

The ionosphere is one of the main factors affecting the accuracy and integrity of satellite-based augmentation system positioning systems. This paper presents the results of a 30-day study of the accuracy and integrity of the European Geostationary Navigation Overlay Service (EGNOS) conducted at the EPOD airport belonging to the Aeroclub of Warmia and Mazury in Olsztyn, in northeastern Poland (the area until recently considered as the edge of EGNOS coverage). Analyses of the parameters characterising the accuracy and integrity of positioning were performed in three calculation variants/modes: with the original EGNOS ionospheric correction, with correction determined by means of Klobuchar algorithm, and finally with modified ionospheric coefficients developed by the CODE. Studies have shown clearly that the original EGNOS ionospheric model gives the best integrity and accuracy results allowing to use EGNOS for approach with vertical guidance procedures, while the Center for Orbit Determination in Europe and Klobuchar models could only be used for non-precision approach operations.

The paper presents a new model for determining the accurate and reliable flight speed of an aircraft based on navigation data from the three independent Global Navigation Satellite System (GNSS) receivers. The GNSS devices were mounted on-board of a Cessna 172 aircraft during a training flight in south-eastern Poland. The speed parameter was determined as the resultant value based on individual components from 3 independent solutions of the motion model. In addition, the standard deviation of the determined flight speed values for the Cessna 172 aircraft was determined in the paper. The resultant on-ground and flight speed of the Cessna 172 aircraft ranged from 0.23 m/s to 74.81 m/s, while the standard deviation of the determined speed values varied from 0.01 m/s to 1.07 m/s. In addition, the accuracy of research method equals to -0.46 m/s to +0.61 m/s, in respect to the RTK-OTF solution. The RMS parameter as an accuracy term amounts to 0.07 m/s for the presented research method.