Acoustic detector
Solar-powered acoustic nodes recognise the sound of engines and propellers with on-board AI: combustion-engine drones up to 3 km, electric drones up to 200 m. Passive and silent, they hear drones that emit no radio signal.
Counter-drone · Airspace security
Detect and stop unauthorised drones over your site
A counter-drone system detects, tracks and, where the law allows, stops unauthorised drones near a protected site. Unauthorised drones are now a routine risk for energy sites, industrial plants, logistics hubs and public events. We deliver layered counter-drone protection, from acoustic, visual and radar detection to mitigation, and integrate it with the way your security team already works.
130–6000MHz mitigation range
14frequency-specific modules
60 GHzmmWave radar detection
3 kmacoustic detection of engine-driven drones
Layered defence
Why one sensor is never enough
Drones differ in size, link and autonomy. A protected site needs several layers that back each other up, sized to its threats, terrain and regulations.
Radar modules, RF mitigation modules, antennas and calibration targets come from our partner Tyko Tech; Perfsol designs the site coverage, integrates the system and supports it.
Detect
Radar, acoustic and visual detectors watch the airspace together, so a drone missed by one sensor is caught by another.
Assess
Tracks, video and alerts brought into one operator view, so the team sees what is approaching and decides quickly.
Mitigate
Modular RF mitigation across 14 frequency bands from 130 to 6000 MHz, scalable from one module to the full set as the threat picture requires.
Intercept
Interceptor drone concepts that physically stop an intruding drone over the protected site when RF mitigation is not enough.
Detection
Three ways to detect a drone
Each sensor has a blind spot: radio silence defeats RF detection, fog limits cameras, clutter confuses radar. Acoustic, visual and radar detectors combined leave a drone very few ways to approach unnoticed.
Visual detector
Day and thermal cameras with on-board AI detect, classify and track drones, tell them apart from birds, and record video evidence of every incident, day and night.
Radar detector
Compact 60 GHz FMCW radar modules with a 3Rx / 2Tx MIMO array and up to 220° field of view measure range and movement in any light and weather.
One picture
Detections from every sensor are fused into one track with one alert, cutting false alarms and pointing cameras and mitigation at the right object.
Acoustic detection grid
Solar-powered listening posts for borders, coasts and remote sites
A distributed grid of solar-powered acoustic nodes on masts and buoys listens for drones, aircraft, missiles and boats. Each node processes sound with on-board AI, estimates the direction of arrival and shares detections over a mesh network; several nodes together triangulate position, course and speed.
Detection range
- Drones and uncrewed boats with combustion enginesup to 3 km
- Propeller aircraftup to 3 km
- Cruise missilesup to 3 km
- Drones and uncrewed boats with electric motorsup to 200 m
Node specification
- SensorMicrophone, 40 Hz – 5 kHz, sensitivity −10 dBFS, signal-to-noise ratio 74 dB, sampling up to 44.1 kHz
- Response12 s from sound to detection on the node
- Environment−30 °C to +40 °C; electronics IP68, microphones IP57
- Weight2.5 kg including mounting
- PowerPoE 48–53 V DC, or autonomous: 200 W solar panel, MPPT controller up to 240 W, battery up to 64 Ah, 5 / 12 / 24 V outputs
- DataEthernet, from 32 kbit/s; nodes exchange structured detections over a resilient mesh
What the grid does
- Passive detection of airborne objects, surface vessels and uncrewed boats
- Direction of arrival on every node
- Multi-node triangulation for location, course and speed
- Automated alerts with a confidence score
- Cues for cameras, mitigation and interceptor drones
- Integration with the command and situational-awareness system of your choice
Design targets
- Availabilitymore than 95 % network availability
- Alert latencyunder 60 seconds
- Autonomymore than 10 days without sunlight
- Signaturelow acoustic and radio signature
Watchtower node
Twin parabolic reflectors on a mast or tripod for long-range listening over borders, perimeters and open terrain.
Compact node
A single sealed unit for places without power or roads, running autonomously on solar power.
Smart buoy
Floating nodes that extend the grid over coasts and archipelagos and also hear surface vessels and uncrewed boats.
Built for borders and early warning, remote wilderness with no grid power or roads, and coastal and maritime sites; works through satellite-navigation disturbance and four-season weather.
Configurations
Permanent installations and field kits
Permanent installation
Indoor equipment rooms with remote dome antennas for plants, substations, warehouses and other facilities that need protection around the clock.
Deployable kit
Configurable modules, antennas and reflectors packed for fast set-up at temporary sites, events and convoys.
Antennas and amplifiers
High-gain omnidirectional and directional antennas, and power amplifiers up to 200 W, chosen for the geometry of each site.
Calibration targets
Luneburg lens and corner reflectors for radar calibration, cross-section evaluation and realistic test scenes.
Delivery
From site survey to a system that stays ready
Our engineering services cover every step, from the survey to long-term support.
- Site survey: threat picture, terrain, RF and acoustic environment, and neighbouring systems
- Placement of acoustic, visual and radar detectors for overlapping coverage
- Design of sensor and mitigation coverage for the site
- Installation, tuning and acceptance testing with calibration targets
- Integration with video surveillance, alarms and secure video via Cast
- Operator training, maintenance and updates as drone threats change
Regulation
RF mitigation and interception are regulated activities. We supply these capabilities only to operators authorised to use them, in line with the radio, aviation and export-control rules of their country, and we help clients establish what is permitted at their site.
Questions buyers ask
What is a counter-drone system?
A counter-drone system detects, identifies and tracks unauthorised drones near a protected site and, where the law allows, mitigates them. Ours combines acoustic, visual and radar detection, fuses them into one track and connects to the site's security tools.
How far can the system detect a drone?
It depends on the sensor and the drone. The acoustic nodes we deploy detect combustion-engine drones at up to 3 km and electric drones at up to 200 m in good conditions, according to the supplier's datasheet. Radar and camera coverage is designed for each site in the survey.
Can it detect drones that do not transmit any radio signal?
Yes. Acoustic nodes, cameras and radar detect the aircraft itself, so they also see drones flying pre-programmed routes and fibre-optic drones, which RF detectors miss.
Who can use RF mitigation?
Only operators authorised under their country's radio, aviation and export-control rules. We supply mitigation, across 14 modules from 130 to 6000 MHz, only to such operators. Detection on its own can be used far more widely.
How does a project start?
With a site survey: the threat picture, terrain, RF and acoustic environment and neighbouring systems. We then design sensor coverage, install and tune the system, and run acceptance tests before handover.
From the blog
Further reading from our engineers
Drone detection and counter-droneAcoustic drone detection: how it works, where it fits and how to deploy it
Acoustic drone detection explained: how sensors hear drones with no radio link, how far they reach, their limits and how to deploy a sensor network.
Drone detection and counter-droneWhat Europe's critical sites can learn from Ukraine's counter-drone experience
One night in November 2026 Ukraine faced 163 drones. Four counter-drone lessons for European airports, energy sites, ports and drone builders.
Drone detection and counter-droneFibre-optic drones: why jamming does not stop them and how to detect them
Fiber optic drones fly on a glass fibre, not radio, so jamming and RF detectors miss them. How they work, their limits and how critical sites detect them.
Next step
Concerned about drones over your site?
Tell us what you need to protect, its size and surroundings, and what you have seen in the air. We will propose an assessment.