Sentinel IDS – Intruder Detection Sonar

Sentinel IDS – The world’s most deployed Intruder Detection Sonar


Our latest generation Sentinel IDS is capable of detecting, tracking and classifying underwater targets including divers and drones.

Sentinel IDS is used globally to protect critical national infrastructure, ports and harbours, military operations and ports, private and commercial yachts, commercial vessels and waterside properties.

Sentinel automatically detects, classifies and tracks subsea threats approaching your protected area or asset, such as a diver, swimmer delivery vehicle or unmanned drone. Our latest generation IDS, Sentinel 2, adds advanced Simultaneous In-band Active and Passive Sonar capability (SInAPS®) to identify and protect, at ranges of up to 1500m for mini-subs and diver detection at up to 1000m.

Sentinel is an intuitive system that will automatically inform the end user of any potential threat without the need for any sonar-trained personnel.

Depending on your application, Sentinel can be supplied in either a portable and mobile package for rapid deployment where temporary underwater security is required or as a permanently installed system for continuous protection of a known asset or perimeter.

Sentinel IDS
New Sentinel Screen

Display Controls

Passive View

Passive Track

Active Track

Active PPI

Zoom View

Tracking Information

Control Panel

System Summary

Sentinel at a glance

  • Identifies and classifies threats up to 1500m from any waterside asset or structure
  • Wavefront’s unique SInAPS® technology combines the detection and tracking capabilities of active and passive sonar
  • Simultaneous Multiple Target Tracking (MTT)
  • Super-Inheritance® to maintain single track across multiple sonar heads
  • Target zoom allows improved target classification via high resolution, enhanced speed replay
  • Historical tracking data for enhanced threat evaluation
  • Response times reduced by rapidly elevating track alert levels using automated Active Passive Track Correlation (APTC)™
  • Comprehensively updated Graphical Display Processor (GDP)
  • Options for rapid overboard, permanent or floating deployment
  • Simple integration into Command and Control (C2) systems for above and below water protection

Sentinel Sonar is suitable for:

Port and harbour security

The reliable detection of underwater targets in the acoustically hostile environment of a seaport, harbour or marine terminal using sonar is a notoriously difficult challenge to overcome. Constant vessel traffic, noise from active depth sounders and a complex thermal structure characterise the scene.

Sentinel has been specifically designed to cope with these conditions, including ‘brown’ water, shallow water and tidal harbours where vessel activity results in a lot of disturbance in the water column. The system’s unique detection, classification and tracking software has been proven to operate in all environmental conditions and is capable of tracking multiple targets in real-time.

Critical National Infrastructure

Due to their strategic and economic importance, critical national infrastructure facilities such as nuclear power plants, dams, LNG terminals and offshore oil platforms represent attractive targets for sabotage.

Whilst these CNI installations have stringent above-the-water security measures, including physical barriers, access control radar and long range opto-electrical sensors, they are not generally equipped to detect intrusions from below the water. That’s why constant, real-time underwater monitoring using Sentinel will help ensure your facility is fully protected.

Naval vessels

Naval ships anchored off the coast or berthed in ports and dockyards are difficult assets to protect because of their size and proximity to commercial shipping traffic, open shipping lanes and leisure users. Physical measures such as floating barriers offer ships protection against surface attack using fast boats, divers using easily acquired scuba equipment remain a significant, yet hard to detect threat.

Sentinel’s compact sonar can be deployed using its own cable over the side of small craft patrolling inland waterways, through the hull of a naval vessel (e.g. Offshore Patrol Vessels) or lowered on a lightweight frame directly onto the seabed. If required, track data can also be exported via an open, industry standard interface to the vessel’s Combat Management System or integrated bridge.

Superyachts, coastal residencies, cruise ships

Sentinel provides reliable, effective and affordable security for properties and vessels considered to be vulnerable to unauthorised access from the water. The moment an intruder enters a monitored underwater exclusion zone, the alarm is raised and the threat is tracked. Sentinel’s advance warning of an attack gives security personnel time to assess the threat, intercept it, or simply move the protected vessel away from it – ensuring the safety of owners, guests and crew always comes first.
Sentinel Screen

The Image Zoom window (top left) shows a full-resolution active sonar image automatically centred on the target. This is shown with range as the Y- Axis and azimuth as the X-Axis. The zoom can be used to help the operator to classify the target; in this case groups of bubbles from the diver’s breathing can clearly be seen, confirming it is an open circuit diver OCD.

Image Zoom Window

Sentinel Screen

Up to 10 sonar heads can be displayed on a single command workstation. The Sentinel UI can display the multi-head view in one window, or can tile images from individual heads in the Overview. A tiled example is shown below. The user can drag and zoom the displays to optimise views in any window.

Sentinel Screen

The Sentinel UI allows for easy fine-tuning of the sonar positions relative to the background images – the operator can move and rotate the sonar location in real-time using built-in tools. Additional point to point measurement scan be made from any area of the UI screen.

Benefits of Sentinel for your operations


For very large sites, such as naval bases and container ports, Sentinel sonar heads can be networked together to provide uninterrupted protection. Integration with C2 systems is standard.

Low false alarms

Sentinel’s advanced algorithms intelligently and reliably discriminate a real threat from fauna and flora removing false alarms, freeing up Security personnel to monitor other critical systems.

Nowhere to hide

Sentinel uses advanced Simultaneous In-band Active and Passive Sonar capability (SInAPS®) to identify and protect, at ranges of up to 1500m for mini-subs and diver detection at 1000m.

Why invest in Sentinel IDS?

Why choose Wavefront

  • The world’s most deployed Intruder Detection Sonar
  • Patented technology delivers unique intruder detection capabilities
  • Unmatched 20 years’ experience installing systems globally to safeguard your vessels, oil platforms, waterside facilities and national infrastructure
  • Dedicated R&D team ensures Sentinel IDS® develops in response to evolving threats


  • Free 24/7, 365-day support service for our valued customer base
  • Access to our engineering team to remedy any issues remotely
  • Extended warranty and maintenance support available
  • Flexible and modular design to facilitate any installation scenario and potential future expansion

At a glance

  • The most deployed Intruder Detection Sonar in the world, in service globally since 2007
  • Simultaneous in-band active and passive sonar (SInAPS®) leaving intruders nowhere to hide
  • Simultaneous Multiple Target Tracking (MTT)
  • Sets specific identifiable sonar- return characteristics for even lower false alarm rates
  • Super-Inheritance® tracking data for improved threat identification across multiple sonar heads
  • One of the most compact IDS solutions on the market; take it and deploy it anywhere
  • Commercial-off-the-shelf (COTS) technology that integrates seamlessly with your existing security systems: radar, CCTV...
  • No specialist sonar experience needed; software automates most of the heavy lifting


  • Up to 3,000m diameter protection zone using a single sonar head
  • Diver detection at up to 1000m
  • Detects underwater vehicles up to 1,500m away
  • 100s of targets can be tracked and classified simultaneously
  • Exports track, status and display image data
  • Automated, user definable alarms
  • Up to 10 sonars can be linked to a single tactical display

Installation and deployment options

Wavefront offer a wide variety of installation options for the Sentinel system. Using experience gained over 20 years’ installing intruder detection sonar systems globally, Wavefront are able to offer expert installation advice for a wide variety of scenarios. Installation type is usually determined after an engineer site visit to assess the perimeter that requires protection and understand
the end-user requirement. Installation options include:

  1. Expeditionary or temporary deployment of the Sentinel sonar via seabed frame.
  2. A fixed bracket is a practical, cost effective solution to deploy the sonar from piles and other suitable structures.
  3. A seabed stand provides an optimum sonar deployment method for permanently protecting open areas of water.
  4. Deployment Raft enables mobilisation where no suitable infrastructure exists or rapid deployment is critical.
  5. Rapid Deployment System designed for ship, choke point or event protection where no power or communications is available.
Sentinel Installation Options

Expeditionary Trailer

Designed to take Sentinel IDS deployments to places where no infrastructure exists or rapid deployment is essential:

  • - Integrated diesel generator for fully remote deployment
  • - GNSS
  • - Wireless communications to other networked trailers or Crewed Command Centre
  • - Capable of working in a network of up to 10 trailers/sonar heads for complex environments
  • - Operator interface via pull out/drop down monitor system
  • - Capable of relocation using Land Rover sized vehicle
  • - Equipment climate conditioning for all environments

Crewed Command Centre

Provides a central command centre for multiple Expeditionary Trailers:

  • - Range includes rapidly deployed trailer variant and expandable 20ft ISO container
  • - Climate controlled
  • - Independent power and communications allow the Sentinel Crewed Command Centre to be situated away from deployment locations

Deployment Raft

Designed to enable Sentinel IDS mobilisation where no suitable infrastructure exists or rapid deployment is critical:

  • - Cable connected for power/comms
  • - Lightweight and easily transported with assembly onsite
  • - Launch from jetty or slipway before floating into position
  • - Anchored or tied up alongside
  • - Deployment machine capable of deployment from 1m to 5m depths

Rapid Deployment System

Designed for ship, choke point or event protection where no power or communications is available:

  • - Simple deployment via ship’s davit and towed into position via RIB
  • - Independent power supply capable of 72 hours unattended operation
  • - Wireless communications back to MSC
  • - Available as a containerised solution with a command station including Command & Display console and one or more Rapid Deployment Sentinel IDS systems