An overview of the modulation and channel coding schemes developed for digital terrestrial television broadcasting within the dTTb project

Abstract

The RACE dTTb project (Digital Terrestrial Television Broadcasting), launched in spring 1992, finalized the definition of its first hardware demonstrator during the first quarter of 1994. Development tasks have been shared by dTTb partners in order to realize a complete equipment by beginning of 1995. The objective of the project is to offer a significant contribution for the standardization of the European digital terrestrial television system; this should be based on a well-established experience relying on field trials using real-time hardware. Therefore, this first demonstrator will provide a large flexibility in relation with service facilities and network operation facilities. Concerning service facilities, the chosen modulation and channel coding schemes should allow multiprogramming capabilities as well as hierarchical services, with downward and upward compatibilities. This means that fixed as well as portable reception should be optimally supported. Concerning network operation facilities, the system will be designed to handle the most stringent multipath propagation conditions. This opens the possibility to operate Single Frequency Networks (SFN), which allows for an optimized field strength distribution, thus avoiding the use of very high power transmitters and reducing the frequency re-use distances.