Research project SIRENE: Green wave for rescue vehicles

The SIRENE project team is developing a navigation system especially for emergency vehicles and a special program for traffic lights,

“Braunschweig is the first city in Germany to introduce a ‘digital siren and flashing light’,” reports the Braunschweig Newspaper. This innovation is an interim result of the research project SIRENE that the PTV Group is involved in. But what exactly is the project about? We talked with Silke Forkert from the PTV Research Team and Florian Weichenmeier, a PTV expert, about this unique project.

Compass: Could you please briefly explain what SIRENE is all about?

Silke Forkert: SIRENE is a research project commissioned by the Federal Ministry of Transport and Digital Infrastructure (BMVI). Its aim is to develop various measures, such as green waves and optimised routing, that help rescue vehicles reach their destinations faster. In urban areas, ambulances or other rescue vehicles are often delayed due to dense traffic or construction sites. When using sirens and flashing lights, the rescue teams do not have to stop at red lights; however, this can be dangerous for traffic crossing at the intersection. One of the project goals is to develop a navigation system specifically designed for emergency vehicles. It will then be possible to include even short-term traffic changes in route planning.

Compass: In Braunschweig, the digital siren and flashing light was introduced in the course of the project. How does it work?

Florian Weichenmeier: The rescue vehicles send messages to all nearby vehicles via so-called V2X communication, a special radio technology that connects vehicles with other vehicles or the road infrastructure. A display integrated into the car alerts drivers to approaching emergency vehicles before they are seen or heard. This allows them to avoid the scene or pull over to make room for the emergency lane.

Compass: What is PTV’s project task?

Florian Weichenmeier: Our software PTV Epics is used to control the traffic lights. This technology enables traffic-adaptive signal control, for example to reduce stop-and-go and ensure smooth traffic flow in the city centre. For SIRENE, we have adapted the software in order to prioritize safety and rescue vehicles.

The vehicles communicate via V2X communication, indicating that they need green waves. Our software makes sure that the traffic lights change to green, so that the emergency vehicles can go straight past the intersections, without having to slow down, if possible. This helps increase safety at the intersection and allows the rescue team to get to the scene much faster.

Florian Weichenmeier is technically involved in the project at PTV.

Compass: What stage has been reached? Is the solution already up and running?

Florian Weichenmeier: We have extended PTV Epics with the necessary functionalities and are currently testing the application in a simulation using PTV Vissim. It is planned to test it in real life at a traffic light system in Braunschweig. Our project partners are currently setting up a complete system that covers the entire communication chain, from the on-board unit (OBU) to the road-side units at the traffic lights and from centralized route calculation to message transfer to the traffic computer. Up to 35 additional signal control systems with conventional control methods will have to be connected in order to enable fire brigade prioritization. But they will have to be extensively redesigned. Using PTV Epics as addition would make sense as our software does not require this additional planning step and is much more flexible and easier to use.

Compass: And what is on the SIRENE agenda over the next few months?

Silke Forkert: We will continue to maintain a lively exchange with the other project partners. In autumn, a project progress presentation will take place after half of the project. Another user meeting is also planned in order to remain in direct contact with the system users.

Florian Weichenmeier: The research partners are very concerned about data security and data protection. I hope that this will result in a sustainable structure that can easily be transferred to other cities and scenarios.


The research project ‘Acceleration of Safety and Rescue Operations through Green Waves and Optimised Routing – SIRENE’, commissioned and funded by the Federal Ministry of Transport and Digital Infrastructure (BMVI), extends over a total period of three years until 2020. The network coordinator is the Institute for Automation and Communication e.V. in Magdeburg., Germany. In addition to PTV Group, four other partners are involved: AFUSOFT Kommunikationstechnik GmbH, Königsbach-Stein, the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt e.V. – Institut für Verkehrssystemtechnik, Braunschweig), GEVAS software Systementwicklung und Verkehrsinformatik GmbH, Munich, and the City of Braunschweig – Fire Department. The project volume amounts to EUR2.57 million, the BMVI’s funding share accounts for 78 percent.