Satellite based turbo-coded, blind-equalized 4-QAM and 16-QAM digital video broadcasting

The pan-European digital satellite video broadcasting (DVB-S) system´s performance is characterized and improved with the aid of turbo coding and multi-level modulation. Specifically, various configurations of blind equalizers and convolutional as well as turbo codecs operating at different code rates were investigated. The standard system´s performance was improved upon replacing the conventional convolutional codec by a turbo codec. Lastly, the feasibility of employing blind equalized 16-level modulation within the DVB-S system is demonstrated, potentially doubling the available bit rate and hence improving the associated video quality at the cost of a higher signal-to-noise ratio (SNR) requirement. This extra transmitted power requirement can be eliminated upon invoking the more complex turbo codec, which requires lower transmitted power for attaining the same performance as the standard convolutional codes