How Authorities Use RF Direction Finding to Detect Drones – A Practical Use Case

Drones are becoming increasingly accessible, maneuverable and inconspicuous. But regardless of their shape or size, they all communicate via radio signals – be it for navigation, control or video transmission. For security and defense agencies, detecting these signals is key to preventing threats before they escalate.

This article shows how a fictional security agency uses RF-based direction finding with Narda’s SignalShark to monitor airspace and detect unauthorized drones.

The challenge: Fast detection in complex environments

A city security team has recurring problems with drones flying over restricted areas near government buildings. Visual detection often comes too late, and radar performance is inconsistent due to building reflections.
The team needed a solution that could passively detect drone signals and localize their origin, even in the presence of RF noise and GNSS interference.

The solution: SignalShark + ADFA

By using SignalShark with the ADFA antenna, the team uses the Angle of Arrival (AoA) to determine the direction of incoming drone signals. In larger areas, multiple SignalSharks enable TDoA-based localization, providing real-time geolocation through triangulation.

Key benefits:

Fast, passive acquisition of C2 and telemetry signals
Resistant to GNSS spoofing and jamming
Scalable integration via API with command and control systems
Real-time data export (VITA49) to external signal analysis tools

The result: situational awareness before visual contact

The team can now detect and track drones before they enter restricted airspace, giving them the lead time they need to assess the situation and respond. RF-based detection has become an important part of the C-UAS strategy.