BDBOS and Dansk Beredskabskommunikation Extend Public Safety Network Radio Coverage at Fehmarnbelt Tunnel
A joint rescue concept was agreed between Germany and Denmark for the duration of the construction period of the Fehmarnbelt Fixed Link to ensure rescue operations in the border region by expanding the critical communications network on both sides.
The "Fehmarnbelt Fixed Link" has been under construction since 2019 between Puttgarden on the German island of Fehmarn and Rødbyhavn on the Danish island of Lolland: Where ferries have previously transported people and freight, a combined road and rail connection between the greater Hamburg and Copenhagen areas will be created by 2029 in a newly constructed immersed tunnel. Since the work at sea involves potential hazards, a joint rescue concept was agreed between German and Danish authorities for the construction period.
Lack of radio coverage in the border region
The aim of this concept was to be able to deploy rescue units from both countries across the entire construction area. The border region between the two countries posed a particular challenge: In order to limit the field strengths¹ in the neighboring country, the digital radio networks of both countries were originally built in such a way that neither is able to fully cover the entire area of the border region. This situation inevitably made joint rescue operations in the construction area more difficult, as neither German emergency services off the Danish coast nor Danish emergency services off the German coast can access their own network.
Measures to expand the digital radio networks
In a first step, an operator agreement was therefore reached between BDBOS on the German side and DBK A/S (Dansk Beredskabskommunikation) on the Danish side. In this agreement, both sides agreed that the networks could radiate deeper into the respective neighbor's territory for the duration of the construction period in order to ensure radio coverage on the "opposite" bank as well. This agreement should also remain in place in the later operational phase in order to be able to react quickly to accidents in the tunnel, for example. In a second step, the infrastructure had to be upgraded. In Germany, the Authorized Body Schleswig-Holstein set up another network element for the BOS digital radio network at the existing location, the sector antenna of which is mainly directed in a north-easterly direction. Since this new network element serves to supply the twelve-mile zone², the costs for its construction were borne entirely by the federal government.
Measurements confirm secure digital radio supply
With the completion of the network element, one last step was taken: the final radio measurement at sea to confirm the quality of the supply. For this, the authorized body commissioned the service provider Dataport AöR, whose measurement team carried out measurements around Fehmarn for an entire working day. Appropriately, the measurements were carried out on board the "FEHMARN", the coastal boat of the Schleswig-Holstein water police stationed in Heiligenhafen. The radio measurements confirmed the very good forecast values. Digital radio supply is thus guaranteed during the construction period.
After the basic construction work has been completed, further work on the digital radio network is to be carried out: the planning and construction of an object supply in the approximately 19-kilometer-long structure in order to ensure radio coverage with both networks in the tunnel and at both tunnel portals.
- The electric field strength is the measure of the strength and direction of an electric field, i.e. the ability of a charge to exert force on other charges.
- The twelve-mile zone is a coastal strip approximately 22.2 km wide (12 nautical miles) that belongs to the territory of a coastal state.
