Shore-to-ship data transmission utilizing the DRM system

Digital Radio Mondiale (DRM) is the new standard for digital broadcasting in the AM bands below 30 MHz. DRM is an interesting candidate for replacing the current standard of military HF shore-to-ship communication. That standard (STANAG 4481, and modulation according to STANAG 4285) utilize the 6 kHz wide independent sideband channels. Employing IPv6 transmission protocols is mandatory for shore-to-ship communication. The paper presents the methodology employed to investigate the usability of the DRM system for shore-to-ship communication. Firstly, test transmissions are conducted over several hundreds of hours, distributed over several months, towards the North Atlantic target area as well as the North Sea, the Baltic and the Mediterranean Sea. Field strength, channel characteristics and bit error patterns are measured on board a frigate of the German Navy. Secondly, a prediction about the coverage of the DRM signal is performed with tools such as WPlotf. Planning parameters for digital broadcasting services are taken into account rather than AM services only.