A Digital Modulation Scheme for Digital Satellite Broadcasting

Digital modulation schemes for satellite broadcasting, such as ISDB (Integrated Services Digital Broadcasting), are investigated. The study must take into account the following conditions when using a 12 GHz band for digital broadcasting. The transmission scheme has to satisfy the criteria of WARC-BS. In addition, service availability must be compatible with conventional FM television services which are in use now. This is because simulcast services for digital and FM television will be necessary when digital broadcasting begins. This paper introduces a modulation sheme and suitable tansmission rate. This study used an ISDB transmission format which includes as error correction code comprising shortened difference set cyclic code (1016, 772). Characteristics of a broadcasting satellite transponder and mass-produced satellite receiver are simulated. Results show that ISDB service in a 12 GHz band is feasible using a 40 Mbps QPSK sheme. This is confirmed by simulations and indoor experiments.