The BDBOS is responsible for the overall coordination of the introduction of BOS (security authorities and organisations) digital radio. The system technology for the BOS digital radio network to be set up is based on the professional TETRA mobile communication standard (Terrestrial Trunked Radio) and will replace the analogue radio technology. TETRA was standardised in 1995 by the European Telecommunications Standards Institute (ETSI) as digital trunked radio. Trunked radio allows the wireless exchange of the information of closed user groups.
Digital trunked radio is a mobile application for speech or data transmission having one or more cells. It operates in the 400-MHz range (public safety organisations (BOS)) and in the 900-MHz range (other public and private enterprises).
As in the case of the mobile systems GSM and UMTS, TETRA uses vehicle terminals and mobile phones as terminal equipment and base stations which establish links to other points in the network. When a terminal crosses the border between two cells, handover takes place which means that an existing link is passed on to the new cell. Nationwide coverage in Germany is currently estimated to require about 5000 base stations. Whereas various TETRA networks are already being used by commercial companies in Germany, the "Bundesanstalt für den Digitalfunk der BOS" is currently coordinating the establishment of a TETRA network for the BOS which will probably be completed in 2013.
As the base stations of TETRA networks operate with a radiated power of more than 10 watts (EIRP), they are monitored by the Federal Network Agency for adherence to the limits for the protection of persons exposed to electromagnetic fields.