GNSS RFI Localization using a Hybrid TDOA/PDOA Approach
Ryan C. Blay and Dennis M. Akos, University of Colorado Boulder
Location: Grand Ballroom G
Alternate Number 1
Interference in GNSS receivers has been a significant concern for some time with the advent of spoofing and jamming. In order to detect and localize the jammers, the automatic gain control (AGC) can be leveraged to notice an increase in power, and time-difference-of-arrival (TDOA) and power-difference-of-arrival (PDOA) algorithms can estimate the position of the emitters. In this paper, there will be a synthesis of TDOA and PDOA to estimate the most likely location of the emitter using a novel weighted approach. Even though TDOA algorithms are more precise than PDOA algorithms, the hyperbolas that result from TDOA sometimes do not all intersect in the same location. Most often this is due to multipath or blocked line-of sight which delays the signal reaching the receivers. PDOA can supplement the TDOA result by providing a rough estimate that can distinguish one TDOA intersection from another. This results in a higher confidence in the estimated location and determines a baseline point to then iterate on. In a dynamic approach, this would allow an emitter’s location to be tracked through time more accurately than either algorithm alone.