Evaluating the vulnerability of several geodetic GNSS receivers under chirp signal L1/E1 jammingBažec, Matej (Avtor) Dimc, Franc (Avtor) Pavlovčič Prešeren, Polona (Avtor) GNSS jammergeodetic GNSS receiverssignal losscarrier-to-noise-ratioUnderstanding the factors that might intentionally influence the reception of global navigation satellite system (GNSS) signals can be a challenging topic today. The focus of this research is to evaluate the vulnerability of geodetic GNSS receivers under the use of a low-cost L1 GPS band and E1 Galileo frequency band (L1/E1) frequency jammer. A suitable area for testing was established in Slovenia. Nine receivers from different manufacturers were under consideration in this study. While positioning, intentional 3-minute jammings were performed by a jammer that was located statically at different distances from receivers. Furthermore, kinematic disturbances were performed using a jammer placed in a vehicle that passed the testing area at various speeds. An analysis of different scenarios indicated that despite the use of an L1/E1 jammer, the GLONASS (Russian: Globalnaya Navigatsionnaya Sputnikovaya Sistema) and Galileo signals were also affected, either due to the increased carrier-to-noise-ratio (C/N$_0$) or, in the worst cases, by a loss-of-signal. A jammer could substantially affect the position, either with a lack of any practical solution or even with a wrong position. Maximal errors in the carrier-phase positions, which should be considered a concern for geodesy, differed by a few metres from the exact solution. The factor that completely disabled the signal reception was the proximity of a jammer, regardless of its static or kinematic mode.20202021-07-14 13:20:48Članek v reviji128469UDK: 528.8ISSN pri članku: 1424-8220DOI: 10.3390/s20030814COBISS_ID: 2963811sl