satellite DMB (S-DMB)
Satellite DigitalMultimedia Broadcast (S-DMB) is a combination of satellite and terrestrial broadcasting. It is a special service for digital broadcasting with which mobile end users can receive multimedia services such as mobile TV or radio.
In the layer model of S-DMB, a multicast layer is implemented on top of the terrestrial unicast transmission of the UMTS network. S-DMB systems operate with geostationary satellites( GEO) that irradiate Europe with umbrella radio cells with diameters of 700 km to 1,000 km. These radio cells can cover more than 90% of the reception range of 3rd generation mobile terminals in the outdoor area. To achieve these values and radiation penetration in buildings, the received RF power must be above 15 dBm( decibel milliwatts), which corresponds to a transmit power( EIRP) of the satellite of 72 dBW(decibel watts).
The powerful GEO satellites used Frequency Division Duplex( FDD) and WCDMA for downlink transmission and Fixed Satellite Service ( FSS) for terrestrial connection to the 3G access network; terrestrial transmission between the radio network and UMTS/ GSM terminal is via a corresponding air interface.