Distinguish navigation (position fixing and route following) from guidance (bringing the weapon to and onto the target in the terminal phase). A drone often combines several methods precisely to be robust against disruption.
| Method | How it works | Strength / weakness |
|---|---|---|
| GNSS (GPS/Galileo/GLONASS) | Position from satellite signals | Accurate — but jammable and spoofable |
| Inertial navigation (INS) | Dead-reckoning with gyros/accelerometers | Immune to jamming; drifts over time. Often GPS/INS coupled |
| Visual / terrain-following | Scene-matching (TERCOM/DSMAC on cruise missiles), visual-inertial odometry, optical flow | Works without GPS; needs vision/map data |
| Terminal guidance & tracking | EO/IR seeker with lock-on-and-track, AI target tracking (Lancet), laser designation/beam-riding, radio/beacon homing | Follows a moving target in the final phase; the essence of 'tracking' |
Why it matters
Counter-UAS by EW stands or falls with the method used. GPS jamming works against purely GNSS-dependent drones, but not against INS-, visually- or AI-guided systems. Tracking in the terminal phase (EO/IR or computer vision) also makes a drone insensitive to cutting the control link: once locked on, it completes the attack on its own. A satellite link (Starlink, see 1.8) is not guidance but a datalink: it keeps the operator in the loop beyond the horizon.