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Passive RF Geolocation

DetectionOpen-Source Verified

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 details

⚠ 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

  • DroneShield / CRFS — passive RF C-UAS product documentation
  • Janes — Passive RF C-UAS (2024)