Drm mw nvis nighttime quality assessment and channel analysis

Laburpena

In the last two decades there has been a speed up in the transition from analogue technology to digital technology in the communications systems. Using digital technology in coding and modulation, it is possible to robustly broadcast the information, increasing the quality of the service for the same spectral occupancy, while allowing usage of lower transmission power. In the beginning of the century, finally, the broadcasting bands under 30 MHz also took advantage of the usage of digital technology. The DRM system is the only universal and non-proprietary digital broadcasting system dedicated to the bands under 30 MHz, that is able to provide a near-FM audio quality. The system has been standardized by the ETSI and IEC. Furthermore, it is recommended by the ITU to be introduced in the HF bands in all regions of the world and in the LW and MW bands in region I and III.The NVIS MW Nighttime propagation was an absolutely untested system using the DRM system. This thesis makes contributions in the quality assessment of the system, the channel requirements and the planning of digital systems using this kind of propagation. The present thesis is based on a collaboration project between two members of the DRM consortium, T-Systems Media & Broadcast GmbH (currently Media Broadcast GmbH) and the University of the Basque Country (UPV/EHU). The work has also been developed under the scope of the system evaluation tasks of the technical committee (TC) of the DRM consortium, which are handled in the system evaluation working group (TC-SE). During the design and execution of the measurement campaign, the work was also supervised by the Technische Fachhochschule Berlin (TFH Berlin).