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Passive RF Geolocation

DetectionOpen-Source Referenced

Multi-node passive sensor network that locates the drone AND its operator by triangulating their RF emissions (TDoA / AoA). Critical for finding pilots of fiber-optic-blind systems and for targeting EW or kinetic effects on the launch site.

How It Works

Three or more passive receivers measure time-difference-of-arrival or angle-of-arrival on the drone's downlink and the operator's uplink. Software fuses the bearings to produce a geolocation fix on both ends of the link.

Technical Specifications

range
5–40 km per node, network-dependent
cost
$80,000–$600,000 per network
deployment Time
Hours (vehicle-mounted) to permanent
crew Required
1–3 operators
weight
20–200 kg per node
power Requirement
Vehicle / mains power

Advantages

  • + Fully passive: no emissions to detect
  • + Locates operator, enabling counter-battery / arrest
  • + Works on any RF-emitting drone, including encrypted military links
  • + Cues other effectors silently

Disadvantages

  • − Useless against fiber-optic drones (no RF)
  • − Requires multiple synchronized nodes
  • − Reduced accuracy in dense urban multipath

Tactical Deployment Tips

  • ▸ Combine with mobile EW or kinetic strike on the located operator
  • ▸ Pre-survey site for best multi-node geometry

Limitations & Vulnerabilities

  • ⚠ Defeated by fiber-optic control
  • ⚠ Brief or hopping emissions reduce fix quality

Drones It Defeats

Drone types ranked by how well this system defeats them, tap any drone for detailsi

Commercial COTS QuadcopterHighMilitary Reconnaissance QuadcopterHighFPV Kamikaze DroneHighHeavy-Lift FPV BomberHighHeavy-Lift Cargo / Resupply UAVHighMini ISR Fixed-WingHighVTOL Fixed-Wing HybridHighCBRN / Hazmat DroneHighMothership / Carrier UAVHighAcoustic-Stealth RotaryHighConverted Agricultural Heavy-LiftHighTactical Fixed-Wing UAVMediumMALE / HALE Strategic UAVMediumSmall Loitering MunitionMediumNaval USV / UUVMediumDecoy / Electronic Warfare DroneMediumMicro / Nano DroneMediumAdversary Interceptor DroneMediumLarge Loitering MunitionLowCoordinated Drone SwarmLowAI-Autonomous Strike DroneLowTethered Surveillance DroneLowJet-Powered UCAVLowHigh-Altitude Pseudo-Satellite (HAPS)LowKinetic Impact / Ramming DroneLowContainerized Swarm Launcher / Modular Launch PodLowFiber-Optic Guided FPVNoneWinged Glide MunitionNoneOne-Way Attack Cruise DroneNoneSea-Skimming Attack USVNone

⚠ How Adversaries Defeat This System

Active enemy adaptations observed in the field, distinct from passive limitations above

  • ▸ Fiber-optic control eliminates RF emissions
  • ▸ Frequency hopping and very short bursts degrade geolocation

Sources & Further Reading

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