Global Navigation Satellite System Signal Generation Method for Wide Area Protection Against Numerous Unintentional Drones

Abstract

This paper presents a method based on the global navigation satellite system (GNSS) interference signals to facilitate wide area protection against numerous unintentional drones. The defensive GNSS signals generated by a single signal generator sweep the authentic GNSS signals, and that the signal tracking loop tracks these defensive signals so that the drones can be guided to a safe zone. The proposed algorithm performs a sweep in the measurement domain by adjusting the time offset of the signal generator, which makes it possible to sweep a wider area. To confirm the possibility of wide area protection, we investigated the signal generation method for the transition of signal tracking locks from authentic to defensive signals in situations where a signal generator cannot identify the drones' positions. We examined the time discrepancy between the authentic and defensive signals and performed the worst-case analysis to determine the minimum sweep range of the time offset. The determined minimum sweep range overcomes the influence of time discrepancy and unconditionally deceives multiple drones regardless of the satellite's position, drones' trajectories, and entry timing. To deceive drones approaching a sphere with a radius of 1 km, the minimum sweep range equals approximately 6 and 3 km when the signal generator is 0 and 2-km away from the center of the sweep region, respectively. The simulation results verified the theoretical analysis and showed that the defensive signals transmitted by one signal generator can deceive multiple drones to the center of the sweep region, which is the intended location.