GNSS Denial

GNSS denial means preventing a receiver from using satellite navigation — GPS, Galileo, GLONASS, BeiDou — most often by jamming. Satellite navigation signals arrive at ground level extraordinarily weak, buried near the background radio noise of the environment, which makes them easy to drown with even a low-power jammer transmitting in the same band. A denied drone typically falls back to inertial navigation, barometric altitude, and whatever its failsafe logic dictates: hover, return toward a launch point it can no longer compute accurately, or land.

Denial is distinct from deception. Jamming removes the signal; spoofing, the related technique, replaces it with a counterfeit. The distinction matters because the defenses differ: jamming resistance comes from antenna design, signal processing, and alternative navigation sources, while spoofing resistance requires authentication and consistency checking.

Military receivers counter denial with controlled-reception-pattern antennas that steer nulls toward jammers, inertial systems that coast through outages, and increasingly visual odometry and terrain matching that need no satellites at all. The same denial that targets drones also blinds friendly precision weapons and logistics, which is why assured positioning is treated as a contested resource rather than a utility.