S-band digital mobile satellite broadcasting system

The digital satellite mobile broadcasting system is one of the most attractive candidates of the next-generation vehicular information systems. However, we have a number of problems to overcome in order to realize such a system technologically and commercially. One of the most serious problems is the service deterioration caused by shadowing. A possible answer to the shadowing problems is the installation of the gap filler and transmission techniques adequate to the utilization of the gap filler. Since each multipath can be demodulated separately and then combined with each other utilizing the RAKE receiver, code division multiplexing (CDM) can provide good transmission quality. In this work we have adopted a combination of the satellite and the gap filler, using CDM with pilot signals as the means of transmission. The system architecture and parameters of this system are described in detail. Moreover, an experimental system was constructed and field experiments were carried out. We conclude that the proposed system can provide high-performance multimedia services