This document describes the development of a DVB-T radiofrequency measurement system along with the development and presentation of its automated software implementation.
The document provides an insight into standard DVB-T signal generation after the transport stream splitter. It presents the energy dispersal (randomizing), the outer coding, the outer interleaving, the inner coding, the inner interleaving, the mapping, the frame adaptation, the OFDM modulation and guard interval insertion operations. It covers the important DVB-T signal parameters, the properties of the transmission channel and the interference during transmission.
In addition, the document includes the schematic structure of a DVB-T receiver and a brief description of its functional sub-elements. It gives a short summary of the NorDig and the MinDigTV technical specification, the requirements and test procedures for the indoor receiver units.
The thesis also discusses the measurement techniques used in DVB-T, the detection of measurable interference, the bit error rate measurement, the spectrum analysis and the constellation analysis. It describes the used measurement instruments and their specific interfaces. It presents the R&S SFQ modulator, the R&S EFA analyzer, the GPIB bus system and the SCPI programming language.
Finally, the document contains the finished software development documentation and a description of its operation. During program development, the goal was to create a framework. Due to the modular program structure, the software can easily be expanded or modified in the future. The thesis contains the software documentation of each component, the GPIB, the modulator controller, the analyzer controller and the measurements modules with graphical interfaces. When this thesis is finished, the software is able to perform transfer characteristic and simple signal level measurements, as well as the necessary instrument calibration.