Combinational Spreading and Modulation Technique for Mobile Satellite DMB Services

The satellite digital multimedia broadcasting (S-DMB) service has been launched and can provide high quality audio, video, and data broadcasting services to the handheld mobile receivers via the geostationary satellite. To cope with the interference caused by the multi-path fading, the current S-DMB system utilizes half of the Walsh codes. To make full use of channel resources in the S-DMB system, a combinational method of the spreading and modulation technique is proposed for use in the S-DMB system. Applying the proposed method of the unused Walsh resources, we can achieve the increment of the system capacity without degrading the service quality of the S-DMB.