Transmission of digital HDTV by satellite: results of studies and experimental trials

The recent penetration of HDTV in television and film production areas, increases the demand of satellite links for the exchange of high quality programme material between production centres. The distribution by satellite of HDTV to cinemas and to special audiences, on the occasion of important sport events and for professional applications, is likely to become another promising field of development for HDTV. This evolutionary scenario is discussed and, for the various HDTV applications, suitable digital transmission systems are identified. The influence of the satellite link components (earth station, transponder, receiving system) on the HDTV service quality is evaluated by computer simulations and experimental tests on a hardware satellite simulator. The results of experimental transmissions at 70 Mbps QPSK carried out via a Eutelsat I satellite and using a HDTV codec developed by EU-250 are reported. Preliminary results are also given of experimental tests carried out on the Olympus satellite, in the framework of various technical investigations conducted by the RAI Research Centre on advanced television, sound and data broadcasting systems. The plans of future experiments over the Olympus communication pay-load, at 30/20 GHz, are briefly reported