Acoustic Sensor Network

Overview#

The Acoustic Sensor Network module provides multi-sensor acoustic detection, classification, and triangulation for military and security operations. The system ingests bearing and time-of-arrival data from distributed acoustic sensors, applies bearing intersection and Time Difference of Arrival (TDOA) algorithms to compute source locations, and classifies detected sounds against a military acoustic signature library. From detection to operator alert, the pipeline completes in under 60 seconds, enabling rapid response to artillery fire, mortar launches, drone activity, and vehicle movement across monitored areas.

Key Features#

Multi-Sensor Triangulation#

Deploy networks of acoustic sensors across an area of operations. The system computes source locations using bearing intersection when sensors report azimuth data, and TDOA algorithms when precise time-of-arrival data is available from synchronised sensor clocks. A minimum of two sensors with bearing data or three sensors with time-of-arrival data produces a fix; additional sensors improve accuracy and provide redundancy.

Military Acoustic Classification#

Classify detected acoustic events against a library of military sound signatures. The classifier distinguishes between artillery fire, mortar launches, rocket-propelled grenades, small arms, rotary-wing aircraft, fixed-wing aircraft, unmanned aerial systems (drones), wheeled vehicles, and tracked vehicles. Classification confidence scores are attached to each detection, and operators can review and correct classifications to improve the model over time.

Shot Counting and Caliber Estimation#

For impulsive acoustic events (gunfire, artillery, mortars), the system performs shot counting to determine the number of rounds fired in a burst or salvo, and estimates caliber category based on acoustic signature characteristics including peak frequency, impulse duration, and energy profile. This data feeds directly into operational reporting and battle damage assessment workflows.

Sensor Health Monitoring#

Each sensor in the network reports health telemetry including battery level, connectivity status, GPS fix quality, microphone gain levels, and ambient noise floor. The system alerts operators when sensors degrade below configurable thresholds, ensuring coverage gaps are identified before they affect detection capability.

Coverage Zone Planning#

Define and visualise acoustic coverage zones based on sensor placement, terrain, and environmental conditions. The coverage planner accounts for sensor detection range, overlapping coverage for triangulation, and terrain masking to identify blind spots. Operators can simulate sensor placement changes before physical deployment.

Sub-60 Second Detection-to-Alert#

The end-to-end pipeline from acoustic event detection through classification, triangulation, and operator notification completes in under 60 seconds. Alerts include the computed source location, classification, confidence score, shot count (where applicable), and a direct link to the event on the operational map.

Use Cases#

• Counter-Battery Fire - Detect and locate enemy artillery and mortar fire positions within seconds, feeding coordinates directly to the effector matching engine for rapid counter-fire response.
• Force Protection - Monitor base perimeters and patrol routes for gunfire, drone activity, and approaching vehicles, providing early warning to force protection teams.
• Airspace Monitoring - Detect and track low-altitude drone activity that may evade radar coverage, providing acoustic cueing to air defence systems.
• Border Surveillance - Deploy persistent acoustic sensor networks along border areas to detect vehicle movement, gunfire, and other activity in areas without line-of-sight coverage.
• Urban Operations - Locate sniper positions and small arms fire sources in urban environments where acoustic reflections complicate manual sound localisation.

Integration#

• Effector Matching Engine - Triangulated source locations feed directly into the effector matching engine for automated target-to-asset pairing.
• Unified Operational Events - All acoustic detections generate events in the unified event timeline with full classification and location data.
• Stone Soup Sensor Fusion - Acoustic tracks are submitted to the Stone Soup fusion framework for correlation with GMTI radar and other sensor tracks.
• Tactical Awareness (TAK) - Acoustic detections are published as CoT events for display on TAK devices in the field.
• 3D Terrain Visualization - Sensor coverage zones and detection locations are rendered on the 3D terrain map.

GraphQL:

acousticSensors

acousticDetections

acousticCoverageZones

registerAcousticSensor

submitAcousticDetection

updateSensorHealth

Last Reviewed: 2026-04-02