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RF Detection / Spectrum Analyzer

DetectionDoctrinal

Passive system that detects drones by their radio frequency emissions. Can identify drone type, direction, and sometimes operator location.

How It Works

Sensitive receivers scan the spectrum for signals matching known drone communication patterns. Direction-finding antennas triangulate position. Advanced systems can also locate the operator's control station.

Technical Specifications

range
1-15 km (depending on drone emissions)
cost
$20,000-$500,000
deployment Time
30 min - 2 hours
crew Required
1-2 operators
weight
10-100 kg
power Requirement
Battery or vehicle power

Advantages

  • + Completely passive — no emissions
  • + Can identify drone type from signal signature
  • + Can locate operator position (high intel value)
  • + Lower cost than radar systems
  • + Can detect drones radar might miss
  • + Works day and night

Disadvantages

  • Cannot detect fiber-optic or autonomous drones (no RF)
  • Cluttered spectrum in urban areas
  • Cannot determine altitude
  • Reduced effectiveness against frequency-hopping
  • Only works when drone is transmitting

Tactical Deployment Tips

  • Combine with radar and acoustic systems
  • Focus on known drone frequencies
  • Use operator location data for counter-fire
  • Deploy sensors in network for triangulation

Limitations & Vulnerabilities

  • Blind to RF-silent drones
  • Urban electromagnetic noise reduces effectiveness
  • Cannot engage — detection only

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

  • Attack from unexpected axis defeats fixed overhead mesh installations
  • Adversary can launch from inside the protected zone (no traversal of corridor)
  • High volume saturates short-range kinetic shooters
  • No single layer is decisive — gap in any layer is exploitable

Sources & Further Reading