GPS Navigation Errors during Auroral-induced Signal Disruptions

GPS is synonymous with precision navigation globally. At high latitudes, ionospheric irregularities related to auroral activity can cause GPS scintillations, which manifest as cycle slips or complete loss of lock on satellites. These disruptions can introduce errors in the navigation solution due to changes in satellite geometries seen by the receiver. At high latitudes, GPS satellite lines-of-sights range from south of receivers to near zenith due to the constellation’s orbital inclination. In this paper, the GPS navigation solution’s sensitivity to satellite geometry will be explored through simulation and multi-instrument observations from Poker Flat, AK. Simulation will be used to quantify various modes of signal interruption – e.g., scintillation and TEC variation – to establish the impacts and interplay of geometry, space weather, and navigation parameters on the fidelity of the navigation solution at high latitudes. As a case study, the simulation findings will be compared against navigation solutions derived with data from the 2015 Mahali Experiment in central Alaska where scintillations were tracked using a distributed network of receivers and precisely correlated with measurements by auroral cameras and the Poker Flat Incoherent Scatter Radar (PFISR).