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Queue Detection System

Navtech's queue detection system detects queuing traffic on a highway or in a tunnel using 360° long-range radar.

Operators can use the information to set warning signs and adjust speed limits to slow traffic helping to prevent accidents.


What is queue detection?

Queue detection is the detection of heavy flow and queuing traffic on a motorway or in a tunnel.

On roads with fast moving traffic, queues can result in multi-vehicle accidents, especially in poor visibility. Operators can only set signs when they are are aware where traffic is building up. This can be hard to identify quickly by monitoring hundreds of camera feeds.

Automatic detection of queuing traffic improves road safety. It means operators can set signs more promptly, giving drivers early warning of a queue ahead and reducing the chances of an accident.

The information can also be used to improve driver experience and reduce congestion by displaying ‘queue after next junction’ messages or reducing speed limits, for example.


Why use radar for queue detection?

Radar works in poor visibility when accidents are more likely to happen. This includes potential multi-vehicle accidents that can occur as a result of queuing traffic.

Tunnels are dirty and dusty environments with changes in light at the portals affecting driver visibility. Roads are dynamic environments that can quickly become challenging: whether it’s low sun reflecting in a driver’s eyes, heavy rain causing spray or dense fog impairing visibility. It is in these conditions that other technologies start to fail, and radar continues to work at the most of critical times.

ITS SOLUTION Why use Navtech's 360° radar solution?

Navtech’s queue detection system automatically detects heavy flow or queuing traffic on a motorway or in a tunnel.

It enables operators to quickly set warning signs and lower speed limits to reduce the chances of a multi-vehicle incident. Our 360° long-range radar can monitor the entire roadway or tunnel 24/7 with fewer sensors. The solution can also integrate into your wider traffic management system to automatically trigger signs when queuing traffic is detected, saving vital time.

As part of our comprehensive automatic incident detection solution, queue detection can be used alongside stopped vehicle detection to ensure operators only get the alerts they need. When queuing traffic is detected, individual stopped vehicle detection alarms from traffic in the queue are suppressed. This ensures operators only get a single queue alarm as opposed to multiple stopped vehicle alerts. Queue detection and stopped vehicle detection are just two of the capabilities that can be delivered from Navtech’s ITS system, all from the same roadside infrastructure.

Real-time situational awareness

Operators have real-time information about traffic on their network or in their tunnel. Queuing alarms automatically clear when traffic flow has returned to normal.

Precise location information

With Navtech's radar-based system operators know the precise location of any queuing traffic.

360° covering the entire freeway

Have visibility across your network with fewer sensors that operate in all conditions. Our radar detect up to 500m in all directions, meaning we cover all lanes and both carriageways.

Multiple applications from one system

Navtech's ITS solution delivers comprehensive automatic incident detection capabilities together with traffic data collection and situational awareness, all from the same system.


Navtech’s Intelligent Transport System (ITS) will find a stopped vehicle or wrong-way driver in seconds so operators can get assistance to road users faster. The same system can provide further actionable data such as vehicle count and classification.

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