In this master's thesis, we studied the impact of unintentional and intentional interference on the operation of GNSS systems and analyzed the responses of the Leica GS18T geodetic receiver and the low-cost u-blox ZED-F9P receiver to such interference. We focused on changes in signal quality and the success of position determination under different interference conditions, evaluating the results through spectral analysis, time monitoring of signal-to-noise ratio (SNR) values, and the receiver's 3D position. We found that GNSS receivers are sensitive to the presence of interference, with differences between receiver types primarily reflected in their interference response strategies. In most cases, the geodetic receiver successfully excluded the interfered signals from the solution in a timely manner, contributing to greater stability, while the low-cost receiver continued to process even heavily degraded signals, often resulting in significant position errors. At higher interference levels and with broader spectral impacts, we also observed the occurrence of intermodulation distortion, which affected the quality of signals outside the directly interfered frequency bands.
|