Optimising quality of service of a new digital radio broadcasting system

Digital Radio Mondiale (DRM) is a new transmission standard designed for broadcasting in the traditional AM bands below 30 MHz. The system was officially launched at the World Radio Congress in June 2003, after which permanent digital broadcasting in the AM bands will begin. Quality of service in digitised AM bands (QoSAM) is a collaboration between QinetiQ, Thales Broadcast & Multimedia, VT Merlin Communications, Deutsche Welle and Radio Netherlands, and partly funded by the European Commission Information Society Technologies Fifth Framework. The key objectives of the QoSAM project are: to develop real-time tools for the measurement of quality of service (QoS); and to develop innovative solutions for the optimisation of the whole digital broadcasting chain, from the audio encoder through the transmission system to the receiver, in a near-real-time automatic feedback loop. This paper introduces the DRM and QoSAM systems, and describes some of the key elements required to relate propagation and system parameters measured by test receivers, to audio QoS.