Hierarchical Modulation and DVB . doc 1 HIERARCHICAL MODULATION AND DVB - S 2

DVB-S2 is the recently defined successor to the current DVB-S standard [4] and DVB-DSNG standard (EN 301210); enabling new services via significantly higher data rates and allowing for a long-term migration. For unicasting applications, the DVB-S2 system includes Adaptive Coding and Modulation (ACM) techniques [1], in order to differentiate the error protection according to the propagation condition experienced by each specific customer. In Hierarchical (H-Mod) two separate data streams are modulated onto a single DVB-S2 stream. Hence the new DVB-S2 receivers may receive both data streams, whereas DVB-S receivers shall remain backward compatible. The novel approach employed in this paper extends ‘Traditional’ H-Mod systems [2] which apply a shift in phase (theta) upon existing modulation schemes to incorporate alternative constellations for the Low Priority Data stream. This new approach provides a foundation for new concepts and techniques in Receiver Design. These techniques have been simulated in software over time varying channels, and implemented using Field Programmable Gate Arrays (FPGA). The results from this research are individually discussed and presented.